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  • 1995-1999  (32)
  • 1955-1959
  • 1999  (32)
  • somaclonal variation
  • transformation
Datenquelle
Materialart
Erscheinungszeitraum
  • 1995-1999  (32)
  • 1955-1959
Jahr
Schlagwörter
  • 1
    Digitale Medien
    Digitale Medien
    A Modular Vector for Agrobacterium Mediated Transformation of Wheat (1999)
    Springer
    Plant molecular biology reporter 17 (1999), S. 323-331 
    Details
    ISSN: 1572-9818
    Schlagwort(e): Agrobacterium ; modular vector ; transformation ; wheat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Wheat (cv Chinese Spring) tissues were transformed using Agrobacterium tumefasciens and a new plasmid modular vector, pMVTBP. We constructed pMVTBP with unique restriction sites connecting (1) the CaMV 35S promoter, (2) a Kozak sequence, (3) the FLAG epitope, (4) the (His)6 epitope, (5) a coding region (for wheat TATA Binding Protein, wTBP) and (6) the CaMV 35S 3′UTR. This vector thus allows easy exchange of different regulatory or coding sequences. Explants of either germinating mature seeds, or immature embryos, were induced to callus for up to two weeks, treated with virulence-induced bacteria for one hour, then regenerated into plantlets. Transient expression of a GUS reporter gene, assayed at about one week, occurred in 10–12% of calluses. Expression of the FLAG-tagged wTBP was also detected, by immunostaining. Stable expression, by selective growth on geneticin, and by GUS expression at about six weeks, occurred in 1–2% of calluses, quite comparable to that achieved by other methods.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1007686408369
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  • 2
    Digitale Medien
    Digitale Medien
    Polymorphism in Polyamide of Dytek®-A and Dodecanedioic Acid (1999)
    Springer
    Journal of thermal analysis and calorimetry 56 (1999), S. 1133-1140 
    Details
    ISSN: 1572-8943
    Schlagwort(e): branched diamine ; melting ; polyamides ; polymorphism ; transformation ; WXRD
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Our X-ray work of Dytek®-A, 2-methyl-pentamethylenediamine, containing polyamides shows polymorphism, whereas the polyamides with linear diamines do not. The polyamide of Dytek®-A and dodecanedioic acid, MPMD-12, is singled out for discussion and compared with the unbranched analogs of polyamides 6,12 and 5,12. Due to the presence of the -CH3 side group in the 2-position of the diamine, the polyamide MPMD-12 exhibits two stable crystal conformations. The new δ polymorph is not seen in linear polyamides 6,12 and 5,12. Studies by DSC polyamide MPMD-12 clearly illustrates at least two crystal forms, γ and δ, coexisting over a wide temperature range, and the isolation of each phase is possible by controlling temperature and time. The DMA modulus in the temperature region between the glass transition (or alpha relaxation) and melting transition shows strong dependence on the thermal history as demonstrated in a study of crystallization kinetics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1010105028316
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  • 3
    Digitale Medien
    Digitale Medien
    The use of image analysis to study developmental variation in micropropagated potato (Solanum tuberosum L.) plants (1999)
    Springer
    Potato research 42 (1999), S. 541-548 
    Details
    ISSN: 1871-4528
    Schlagwort(e): epigenetic variation ; leaf ontogeny ; somaclonal variation ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Potato leaf morphology changes during plant development with the phase shift from vegetative growth to flowering. Image analysis can detect differences in leaf morphology and has been used here to distinguish differences in leaf morphology between potato crops derived from seed tubers and minitubers and between crops derived from different micropropagation protocols. Further, leaf shape parameters can be used to determine the relative maturity of crops. This finding is of economic importance since differences in plant development, for example delayed flowering, are associated with yield parameters. It is hypothesised that image analysis of established microplants can be used as an early evaluation of micropropagation protocols for potato.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF02358170
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  • 4
    Digitale Medien
    Digitale Medien
    Agrobacterium‐mediated transformation of lavandin (Lavandula x intermedia Emeric ex Loiseleur) (1999)
    Springer
    Transgenic research 8 (1999), S. 335-347 
    Details
    ISSN: 1573-9368
    Schlagwort(e): Agrobacterium tumefaciens ; ß‐glucuronidase ; lamiaceae ; lavandin ; neomycin phosphotransferase II ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Lavandin (Lavandula x Emeric ex Loiseleur) is an aromatic plant, the essential oil of which is widely used in the perfume, cosmetic, flavouring and pharmaceutical industries. The qualitative or quantitative modification of its terpenes‐containing essential oil by genetic engineering could have important scientific and commercial applications. In this study, we report the first Agrobacterium tumefaciens‐mediated gene transfer into lavandin. The transformation protocol was optimized by lengthening precultivation and cocultivation periods and by testing five different bacterial strains. We obtained transformed callus lines at a frequency of 40–70 with strains AGL1/GI, EHA105/GI and C58/GI. Transgenic shoots were regenerated from these kanamycin resistant calli and rooted on selective medium with 150 mg l-1 kanamycin. The final percentage of transgenic plants obtained varied from 3 to 9, according to the strain used, within 6 months of culture. The presence of the introduced β‐glucuronidase and neomycin phosphotransferase II genes was shown both by PCR and Southern blot analysis. Transgene expression was investigated using histoenzymatic β‐glucuronidase assays, leaf callus assays and RT‐PCR. Results showed that both β‐glucuronidase and neomycin phosphotransferase II genes were expressed at a high level in at least 41 of the transgenic plants regenerated. This efficient transformation strategy could be used to modify some genetic traits of lavandin (flower colour, pathogens resistance) and to study the biosynthesis of the major monoterpene components of its essential oil (linalool, linalyl acetate, camphor and 1,8‐cineole).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008948113305
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  • 5
    Digitale Medien
    Digitale Medien
    Expression of the Bar Gene Confers Herbicide Resistance in Transgenic Lettuce (1999)
    Springer
    Transgenic research 8 (1999), S. 33-44 
    Details
    ISSN: 1573-9368
    Schlagwort(e): Lactuca sativa ; Agrobacterium tumefaciens ; bialaphos ; phosphinothricin acetyltransferase ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Resistance to bialaphos, a broad-spectrum herbicide, was introduced into Lactuca sativa cv. Evola by Agrobacterium tumefaciens-mediated transformation. A. tumefaciens strains 0310 and 1310, both carrying the bialaphos resistance (bar) and neomycin phosphotransferase (nptII) genes, were used for transformation. Primary transformants were selected on kanamycin sulphate-supplemented shoot regeneration medium. Integration of both transgenes was confirmed by non-radioactive Southern hybridisation. The hypervirulent plasmid ToK47 in A. tumefaciens strain 1310 generated multiple insertions of T-DNA in some transgenic plants; the absence of pToK47 (strain 0310) resulted in single gene inserts in all plants tested. Resistance to glufosinate ammonium was observed in axenic seedlings grown on medium supplemented with the herbicide at 5 mg l−1 and in glasshouse-grown plants sprayed with the compound at 300 mg l−1. Stable expression of the bar gene was observed in R2 generation plants. The kanamycin resistance of R1 seedlings was observed by germinating seeds on medium supplemented with 200 mg l−1 kanamycin sulphate. The presence of NPTII protein and PAT enzyme activity were demonstrated by ELISA and PAT enzyme assay respectively. Transgenes segregated in a Mendelian fashion in some plant lines in the R1 generation; herbicide resistance also segregated in the expected ratio in the R2 generation in most transgenic lines. This study confirmed that an agronomically important transgene can be integrated and stably expressed over several generations in lettuce.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008891216134
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  • 6
    Digitale Medien
    Digitale Medien
    Somaclonal variation in insect‐resistant transgenic sugarcane (Saccharum hybrid) plants produced by cell electroporation (1999)
    Springer
    Transgenic research 8 (1999), S. 349-360 
    Details
    ISSN: 1573-9368
    Schlagwort(e): Bacillus thuringiensis ; Borer disease ; Saccharum ; somaclonal variation ; transgenic sugarcane
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A population of 42 transgenic sugarcane ( hybrid, cv. Ja60‐5) clones expressing a truncated cryIA(b) gene from Bacillus thuringiensis was evaluated in field trials under artificial borer (Diatraea saccharalis Fab.) infection. Five clones displaying the highest borer tolerance were selected and analysed with molecular tools (RAPD, AFLP and RAMP) to verify genomic changes. Results of field trials provided evidence both for the expression of the resistance trait and for the occurrence of limited but consistent morphological, physiological and phytopathological variation, as compared with control plants regenerated from dedifferentiated culture without transformation (C1‐control) or with plants that were clonally propagated in the field (C2‐control). The five elite transgenic clones, selected for consistent borer‐resistance and good agronomic traits, were further evaluated in a large scale field trial. It was found that the majority of agronomic and industrial traits were those of the original cv. Ja60‐5, but that a small number of qualitative traits was different. DNA changes were verified in the five selected clones. A total of 51 polymorphic DNA bands (out of the 1237 analysed bands) was identified by extensive AFLP and RAMP analysis, thus showing rare but consistent genomic changes in the transgenic plants, as compared with C1‐ and C2‐control plants. It is proposed that the increased variability verified in transgenic plants by field trials and DNA analysis is essentially correlated with cell growth in the dedifferentiated state during the transformation procedure. The results, which are consistent with those published in the case of other transgenic plant populations, are discussed in the context of selecting approaches to gene transfer that minimize somaclonal variation. This is important especially in cases, such as that of sugarcane, where success of backcrosses to restore the original genotype is made difficult by the complex ploidy state of the plant.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008900230144
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  • 7
    Digitale Medien
    Digitale Medien
    Transformation of pasta wheat (Triticum turgidum L. var. durum) with high-molecular-weight glutenin subunit genes and modification of dough functionality (1999)
    Springer
    Molecular breeding 5 (1999), S. 377-386 
    Details
    ISSN: 1572-9788
    Schlagwort(e): Triticum turgidum L. var. durum ; pasta wheat ; transformation ; seed protein modification ; flour quality improvement
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Particle bombardment has been used to transform three cultivars (L35, Ofanto, Svevo) and one breeding line (Latino × Lira) of durum wheat (Triticum turgidum L. var. durum). These varieties were co-transformed with plasmids containing selectable and scorable marker genes (bar and uidA) and plasmids containing one of two high-molecular-weight (HMW) glutenin subunit genes (encoding subunits 1Ax1 or 1Dx5). Ten independent transgenic lines were recovered from 1683 bombarded scutella (transformation efficiency thus 0.6%). Five lines expressed either subunit 1Dx5 or 1Ax1 at levels similar to those of endogenous subunits encoded on chromosome 1B. To identify the effects of the transgenes on the functional properties of grain, three lines showing segregation for transgene expression were used to isolate sibling T2 plants which were null or positive for the transgene product. Analysis of these plants using a small-scale mixograph showed that expression of the additional subunits resulted in increased dough strength and stability, demonstrating that transformation can be used to modify the quality of durum wheat for bread and pasta making.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009681321708
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  • 8
    Digitale Medien
    Digitale Medien
    Transformation of the endospermous legume guar (Cyamopsis tetragonoloba L.) and analysis of transgene transmission (1999)
    Springer
    Molecular breeding 5 (1999), S. 521-529 
    Details
    ISSN: 1572-9788
    Schlagwort(e): Cyamopsis tetragonoloba ; β-lactamase inhibitor ; sulbactam ; transformation ; transgene stability ; transgenic guar
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract A procedure for transformation of the large-seeded endospermous legume guar (Cyamopsis tetragonoloba L.) and a study on transmission of the transgenes to offspring generations are presented. Using Agrobacterium tumefaciens with a T-DNA construct harbouring a β-glucuronidase gene (uidA) and a neomycin phosphotransferase gene (nptII), maximum transformation frequencies of cotyledonary explants were obtained using 145 mg/l kanamycin sulfate as selective agent. Carbenicillin and cefotaxime, used for the elimination of Agrobacterium after co-culture, displayed considerable toxicity to guar tissues but replacing most of these β-lactams by the non-phytotoxic β-lactamase inhibitor sulbactam as well as addition of thidiazuron and silver thiosulfate increased transformation frequencies up to 10-fold in total. The presence of the transgenes in the primary transformants was demonstrated by genomic DNA analysis of GUS-positive shoots. Chimaeric plants (5–10%) were identified by GUS analysis at the flowering stage and were discarded. Analysis of the R1 offspring from 17 independent transformants showed that in 41% of those, the uidA gene(s) was expressed and stably inherited consistent with Mendelian genetics. This was also found for the R2 and R3 generations of single copy transformants. On the other hand, a large proportion (47%) of the primary transformants gave R1 offspring in which 100% of the plants were GUS-negative. Analysis of these plants by PCR revealed that, at least, most of the transgene sequences were absent, suggesting that they had not been transmitted from the parent transformants. This occurred at similar high frequencies (40–50%) irrespective of the estimated copy number of the transgenes. Thus, major parts of the transgenes, even when present in multiple copies, displayed aberrant transmission, at a high frequency, in the process of going from the primary transformants to the first offspring generation.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009602722423
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  • 9
    Digitale Medien
    Digitale Medien
    Partial male sterility in transgenic tobacco carrying an antisense gene for alternative oxidase under the control of a tapetum-specific promoter (1999)
    Springer
    Molecular breeding 5 (1999), S. 209-218 
    Details
    ISSN: 1572-9788
    Schlagwort(e): alternative oxidase ; antisense ; male-sterility ; tapetum-specific promoter ; tobacco ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract The alternative oxidase of plant mitochondria is the terminal oxidase of the cyanide-insensitive respiratory pathway and is encoded by a nuclear gene. A 1 kb genomic fragment including exon 3 of the alternative oxidase was amplified by PCR from the genome of Arabidopsis thaliana. This fragment was connected to a tapetum-specific promoter in the antisense orientation and then introduced into tobacco. The pollen viability in three transgenic plants ranged from 2% to 60%. The reduced pollen viability cosegregated with the transgene in a selfed progeny. Immunolocalization of alternative oxidase protein in the immature flower bud section indicated that expression of alternative oxidase protein in tapetum of the transgenic plant was much lower than that of the non-transformant. The histological observation and protein gel-blot analysis showed that the development of pollen grains in the transgenic plant did not progress after the degradation of the tapetum, and the amount of alternative oxidase in pollen grains of the transgenic plant became lower than that of the non-transformant. These results suggested that the alternative oxidase activity in the tapetum has a significant effect on the pollen development.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1009606601521
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  • 10
    Digitale Medien
    Digitale Medien
    Expansive Visibilization of Work: An Activity-Theoretical Perspective (1999)
    Springer
    Computer supported cooperative work 8 (1999), S. 63-93 
    Details
    ISSN: 1573-7551
    Schlagwort(e): activity theory ; action ; transformation ; expansive learning ; intervention ; visibilization ; health care ; medical records
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Informatik
    Notizen: Abstract Work is commonly made visible along two dimensions: the linear and the socio-spatial. Both are limited to depicting work in terms of relatively discrete actions. Activity theory introduces the crucial distinction between collective activity systems and individual actions. Expansive visibilization of collective activity systems offers a powerful intervention methodology for dealing with major transformations of work. The linear and the socio-spatial dimensions of work actions are seen in the broader perspective of a third, developmental dimension of work activity. Four steps are identified in a cycle of expansive visibilization, combining activity-level visions and action-level concretizations. The cycle is examined in detail as it unfolded in an intervention study at a children's hospital in Finland. It is concluded that expansive visibilization, driven by contradictions and seeking to reconceptualize the object and motive of work, is not a straightforward process which can be neatly controlled from above. Coherent analytical explanation and goal-setting may come only after the creation and practical implementation of innovative solutions.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008648532192
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  • 11
    Digitale Medien
    Digitale Medien
    REMI (Restriction Enzyme Mediated Integration) and its Impact on the Isolation of Pathogenicity Genes in Fungi Attacking Plants (1999)
    Springer
    European journal of plant pathology 105 (1999), S. 221-229 
    Details
    ISSN: 1573-8469
    Schlagwort(e): mutagenesis ; transformation ; plant disease ; recombination ; plant pathogenic fungi
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Development of molecular techniques for phytopathogenic fungi aims at the identification of fungal genes whose products are essential for successful infection of the host plant. Initial approaches have relied on isolating candidate genes and generating null-mutations by homologous recombination. Unfortunately, the results of this strategy have not been overly successful. This has led to a search for alternatives which allow an unbiased identification of pathogenicity genes. One method, which has proved successful in several systems, is a tagging mutagenesis procedure termed restriction enzyme mediated integration (REMI). In this mini-review we describe this procedure and review its features and results of its use when applied to the identification of fungal genes required for disease development in planta.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008757414036
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  • 12
    Digitale Medien
    Digitale Medien
    A mini binary vector series for plant transformation (1999)
    Springer
    Plant molecular biology 40 (1999), S. 711-717 
    Details
    ISSN: 1573-5028
    Schlagwort(e): Agrobacterium tumefaciens ; Arabidopsis thaliana ; binary vector ; T-DNA ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A streamlined mini binary vector was constructed that is less than 1/2 the size of the pBIN19 backbone (3.5 kb). This was accomplished by eliminating over 5 kb of non-T-DNA sequences from the pBIN19 vector. The vector still retains all the essential elements required for a binary vector. These include a RK2 replication origin, the nptIII gene conferring kanamycin resistance in bacteria, both the right and left T-DNA borders, and a multiple cloning site (MCS) in between the T-DNA borders to facilitate cloning. Due to the reduced size, more unique restriction sites are available in the MCS, thus allowing more versatile cloning. Since the traF region was not included, it is not possible to mobilize this binary vector into Agrobacterium by triparental mating. This problem can be easily resolved by direct transformation. The mini binary vector has been demonstrated to successfully transform Arabidopsis plants. Based on this mini binary vector, a series of binary vectors were constructed for plant transformation.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1006201910593
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  • 13
    Digitale Medien
    Digitale Medien
    Wnt Signalling in Mammalian Development and Cancer (1999)
    Springer
    Cancer and metastasis reviews 18 (1999), S. 215-230 
    Details
    ISSN: 1573-7233
    Schlagwort(e): transformation ; tumour ; Frizzled ; Dishevelled ; glycogen synthase kinase-3β
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Wnt signalling is involved in a variety of mammalian developmental processes, including cell proliferation, differentiation and epithelial–mesenchymal interactions, through which they contribute to the development of tissues and organs such as the limbs, the brain, the reproductive tract and the kidney. Wnts are secreted ligands that control cell processes via at least two pathways, one of which, the ‘canonical’ Wnt signalling pathway, operates through the cytosolic stabilisation of a transcriptional co-factor, β-catenin. This is achieved by downregulating the activity of a β-catenin turnover complex. Evidence from tumour expression studies, transgenic animals and in vitro experiments suggests that inappropriate activation of the canonical Wnt signalling pathway is a major feature in human neoplasia and that oncogenic activation of this pathway can occur at many levels. Inappropriate expression of the Wnt ligand and Wnt binding proteins have been found in a variety of human tumours. Further downstream, dysregulation of the β-catenin turnover complex, by loss of the Adenomatous Polyposis Coli or Protein Phosphatase 2A proteins, or by activating mutations of β-catenin, has been found in several tumour types, and is believed to be a key step in neoplastic progression. Transcriptional targets of the Wnt pathway include the cellular oncogenes cyclin D1 and c-myc. Activation of the Wnt signalling pathway by various means can therefore be a primary cause in oncogenesis, affecting cell proliferation, morphology and contact inhibition, as well as co-operating with other oncogenes in multistep tumour progression.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1006369223282
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  • 14
    Digitale Medien
    Digitale Medien
    Institutional transformation at South African universities: Implications for academic staff (1999)
    Springer
    Higher education 38 (1999), S. 275-290 
    Details
    ISSN: 1573-174X
    Schlagwort(e): academic staff ; curriculum change ; equity ; governance ; staff development ; student needs ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Wissenschaftskunde und Wissenschaftsorganisation, Hochschul- und Universitätswesen, Museumswissenschaft
    Notizen: Abstract In South Africa the restructuring of the higher education system and the transformation of higher education institutions are located within the country's broad political and socio-economic transition to democracy. This paper focuses particularly on institutional transformation, and pays attention to the implications of the process of transformation for academic staff. The following five interlinked and interdependent issues characterizing institutional transformation in South African higher education are identified: democratising the governance structures of institutions increasing access for educationally and financially disadvantaged students restructuring the curriculum focusing on developmental needs in research and community service redressing inequalities in terms of race and gender. Although the overall effect of institutional transformation is experienced rather negatively by many academic staff members, the paper concludes that academics have to be empowered by means of staff development to remain active partners in the transformation process.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003768229291
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  • 15
    Digitale Medien
    Digitale Medien
    Anaerobic transformation of 1,1,1-trichloroethane by municipal digester sludge (1999)
    Springer
    Biodegradation 10 (1999), S. 297-305 
    Details
    ISSN: 1572-9729
    Schlagwort(e): abiotic ; biological ; cell-free extract ; chloroethane ; dechlorination ; 1,1-dichloroethane ; 1,1-dichloroethene ; digester ; methanogenic ; transformation ; 1,1,1-trichloroethane
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Energietechnik , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Anaerobic transformations of 1,1,1-trichloroethane (TCA), 1,1-dichloroethane (DCA), and chloroethane (CA) were studied with sludge from a lab-scale, municipal wastewater sludge digester. TCA was biologically transformed to DCA and CA and further to ethane by reductive dechlorination. TCA was also converted to acetic acid and 1,1-dichloroethene (11DCE) by cell-free extract. 11DCE was further biologically converted to ethene. This pathway was confirmed by transformation tests of TCA, DCA and CA, by tests with cell-free extract, and by chloride release during TCA degradation. With cell-free extract, acetic acid accounted for approximately 90% of the TCA transformed; tests with live cells indicate that the fraction of TCA transformed by this pathway decreased with lower biomass. The dechlorination of DCA to CA and CA to ethane was not stoichiometric. A high rate of TCA removal was observed under the experimental conditions. The results indicate that removal of TCA in anaerobic digestion should be complete, but DCA and CA could persist in a normally operating digester.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008336103968
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  • 16
    Digitale Medien
    Digitale Medien
    Urban development in East Germany — specific features of urban transformation processes (1999)
    Springer
    GeoJournal 49 (1999), S. 43-51 
    Details
    ISSN: 1572-9893
    Schlagwort(e): housing market ; suburbanisation ; transformation ; urban development ; urban renewal ; East Germany
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Geographie
    Notizen: Abstract The aim of this paper is to analyse the main characteristics of post-socialist urban development in East Germany, especially the differences compared to urban development in other East and Central European countries. In spite of the many similar problems and processes in urban development, specific features of East Germany are characterised by the rapid growth of suburbia, especially in the first phase of transition, by the proceeding activities of urban renewal and revitalisation, and by a lower level of social polarisation and socio-spatial segregation as compared to other post-socialist countries. Important conditions for urban development in East Germany exist in special support programmes, high subsidies and other financial transfers as well as in engaged planning conceptions of the local authorities.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1007016912703
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  • 17
    Digitale Medien
    Digitale Medien
    Selection of downy mildew resistant somaclones, from a susceptible B line of pearl millet (1999)
    Springer
    Plant cell, tissue and organ culture 58 (1999), S. 159-162 
    Details
    ISSN: 1573-5044
    Schlagwort(e): agronomic traits ; Pennisetum glaucum ; Sclerospora graminicola ; somaclonal variation ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Plants regenerated from seed-derived callus of a PNMS 6B line of pearl millet (Pennisetum glaucum (L.) R. Br.) were evaluated for their resistance induced by somaclonal variation for downy mildew disease caused by Sclerospora graminicola (Sacc.) Schroter. Among the 201 lines regenerated, only 3 lines consistently proved highly resistant (free from disease incidence) for up to 5 generations; whereas, 17 lines were resistant (disease incidence ranging from 1 to 9%). Resistance was confirmed by testing the plants under both laboratory and field conditions. The plants were evaluated for their agronomic traits.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1006347113434
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  • 18
    Digitale Medien
    Digitale Medien
    Use of fluorescein diacetate (FDA) to determine ploidy of in vitro watermelon shoots (1999)
    Springer
    Plant cell, tissue and organ culture 58 (1999), S. 199-203 
    Details
    ISSN: 1573-5044
    Schlagwort(e): triploid watermelon ; seedless watermelon ; tetraploid watermelon ; plant breeding ; somaclonal variation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Ploidy of watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai shoots and plantlets was estimated by painting the lower epidermis of intact in vitro-derived leaves with fluorescein diacetate (FDA) and observing fluorescence of guard cell chloroplasts with a microscope and UV light. Leaves from in vitro shoot-tip cultures of known diploid cultivars and tetraploid breeding lines were used to establish the mean number of chloroplasts per guard cell pair. Leaves from diploid and tetraploid shoot cultures had 9.7 and 17.8 chloroplasts per guard cell pair, respectively. This method then was used to estimate the ploidy of shoots regenerated from cotyledon explants of the diploid cultivar Minilee. Approximately 11% of the 188 regenerated shoots were classified as tetraploid during in vitro culture. Putative tetraploids were transplanted to the field and self-pollinated. About 45% of tetraploids identified in vitro produced fruit and viable seed. Chloroplast counts of R1 progeny were used to confirm their ploidy. All of the putative diploids were confirmed diploid and all putative tetraploids proved to be non-chimeric true breeding tetraploids.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1006371516394
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  • 19
    Digitale Medien
    Digitale Medien
    DNA analysis of potato + Solanum brevidens somatic hybrid lines (1999)
    Springer
    Euphytica 105 (1999), S. 103-107 
    Details
    ISSN: 1573-5060
    Schlagwort(e): Erwinia carotovora ; Solanum tuberosum ; somaclonal variation ; RAPD
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Three somatic hybrid lines between potato (cv. While Lady line no. Ke 79, 2n = 2x = 48) + Solanum brevidens (PI 218228, 2n = 2x = 24) were evaluated using randomly amplified polymorphic DNA (RAPD) markers. The lines originated from the same callus but showed different reactions to Erwinia carotovora ssp. carotovora, the cause of potato soft rot. By the use of 48 oligomer primers producing 99 scorable bands, DNA polymorphism were detected on 7 of 12 S. brevidens chromosomes. Loss of certain DNA segments on chromosome 5, 6, 9 and 11 were observed. Some of the variations could have taken place in early callus stage of development; others may have occurred after initiation of individual shoot regeneration. The possible involvement of missing RAPD products specific to one somatic hybrid that shows decreased resistance to bacterial soft rot is discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003451327553
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  • 20
    Digitale Medien
    Digitale Medien
    A promoter from sugarcane bacilliform badnavirus drives transgene expression in banana and other monocot and dicot plants (1999)
    Springer
    Plant molecular biology 39 (1999), S. 1221-1230 
    Details
    ISSN: 1573-5028
    Schlagwort(e): constitutive expression ; GFP ; GUS ; Musa ; ScBV ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A 1369 bp DNA fragment (Sc) was isolated from a full-length clone of sugarcane bacilliform badnavirus (ScBV) and was shown to have promoter activity in transient expression assays using monocot (banana, maize, millet and sorghum) and dicot plant species (tobacco, sunflower, canola and Nicotiana benthamiana). This promoter was also tested for stable expression in transgenic banana and tobacco plants. These experiments showed that this promoter could drive high-level expression of the β-glucuronidase (GUS) reporter gene in most plant cells. The expression level was comparable to the maize ubiquitin promoter in standardised transient assays in maize. In transgenic banana plants the expression levels were variable for different transgenic lines but was generally comparable with the activities of both the maize ubiquitin promoter and the enhanced cauliflower mosaic virus (CaMV) 35S promoter. The Sc promoter appears to express in a near-constitutive manner in transgenic banana and tobacco plants. The promoter from sugarcane bacilliform virus represents a useful tool for the high-level expression of foreign genes in both monocot and dicot transgenic plants that could be used similarly to the CaMV 35S or maize polyubiquitin promoter.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1006125229477
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  • 21
    Digitale Medien
    Digitale Medien
    Selectable marker-free transgenic plants without sexual crossing: transient expression of cre recombinase and use of a conditional lethal dominant gene (1999)
    Springer
    Plant molecular biology 40 (1999), S. 223-235 
    Details
    ISSN: 1573-5028
    Schlagwort(e): conditional lethal dominant gene ; Cre/loxP ; Nicotiana tabacum ; site-specific recombinase ; transformation ; transient expression
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Transgenic tobacco plants were produced that contained single-copy pART54 T-DNA, with a 35S-uidA gene linked to loxP-flanked kanamycin resistance (nptII) and cytosine deaminase (codA) genes. Retransformation of these plants with pCre1 (containing 35S transcribed cre recombinase and hygromycin (hpt) resistance genes) resulted in excision of the loxP-flanked genes from the genome. Phenotypes of progeny from selfed-retransformed plants confirmed nptII and codA excision and integration of the cre-linked hpt gene. To avoid integration of the hpt gene, and thereby generate plants totally free of marker genes, we attempted to transiently express the cre recombinase. Agrobacterium tumefaciens (pCre1) was cocultivated with leaf discs of two pART54-transformed lines and shoots were regenerated in the absence of hygromycin selection. Nineteen of 773 (0.25%) shoots showed tolerance to 5-fluorocytosine (5-fc) which is converted to the toxic 5-fluorouracil by cytosine deaminase. 5-fc tolerance in six shoots was found to be due to excision of the loxP-flanked region of the pART54 T-DNA. In four of these shoots excision could be attributed to cre expression from integrated pCre1 T-DNA, whereas in two shoots excision appeared to be a consequence of transient cre expression from pCre1 T-DNA molecules which had been transferred to the plant cells but not integrated into the genome. The absence of selectable marker genes was confirmed by the phenotype of the T1 progeny. Therefore, through transient cre expression, marker-free transgenic plants were produced without sexual crossing. This approach could be applicable to the elimination of marker genes from transgenic crops which must be vegetatively propagated to maintain their elite genotype.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1006184221051
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  • 22
    Digitale Medien
    Digitale Medien
    Optimisation of procedures for microprojectile bombardment of microspore-derived embryos in wheat (1999)
    Springer
    Plant cell, tissue and organ culture 57 (1999), S. 207-210 
    Details
    ISSN: 1573-5044
    Schlagwort(e): biolistics ; gene expression ; haploid ; transformation ; Triticum aestivum
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Using the PDS-1000/He Biolistic® Particle Delivery System, the microprojectile travel distance, rupture disk pressure and DNA/gold particle concentrations were assessed in order to optimise short and longer-term β-glucuronidase reporter gene expression in microspore-derived embryos of wheat. The effects were also evaluated of using sterile filter paper to support explants and treatment with a high osmoticum medium (0.2 M mannitol/0.2 M sorbitol or 0.4 M maltose). In the optimised procedure, wheat microspore-derived embryos (MDEs), were placed on filter paper and incubated on medium containing 0.4 M maltose, for 4 h pre- and 45 h post-bombardment. Five μl pAHC25 (0.75 mg ml-1 in TE buffer) was precipitated onto 25 μl gold particles (60 mg ml-1 in sterile water), using 20 μl spermidine (0.1 M) and 50 μl CaCl2 (2.5 M). The particles were centrifuged and resuspended in 75 μl absolute ethanol prior to the preparation of 6 macrocarriers. A microprojectile travel distance of 70 mm, a rupture pressure of 1300 p.s.i., and a vacuum of 29′′ Hg were employed. Maltose at 0.4 M in the support medium was the most important factor influencing GUS activity in bombarded tissues. GUS activity, 1 day post-bombardment, reached 52 ± 17 GUS-positive foci/MDE (mean ± s.e.m, n=3), with 17 ± 4 foci/MDE at 15 days, giving a 3.0-fold increase (p〈0.05) compared to expression in MDEs bombarded on medium without a high osmoticum treatment.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1006384525513
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  • 23
    Digitale Medien
    Digitale Medien
    Recovery of transgenic orchid plants with hygromycin selection by particle bombardment to protocorms (1999)
    Springer
    Plant cell, tissue and organ culture 58 (1999), S. 87-92 
    Details
    ISSN: 1573-5044
    Schlagwort(e): ß-glucuronidase ; dendrobium ; hygromycin phosphotransferase ; orchid ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Protocorms of orchid (Dendrobium hybrid) were transformed by microprojectile bombardment with a helium-pressured PDS 1000 particle gun. Gold particles coated with plasmid DNA containing ß-glucuronidase (GUS) and hygromycin phosphotransferase (Hpt) marker genes were used. Potentially transformed tissues were identified by active growth on MS medium supplemented with 50mg l-1 hygromycin. After 4–6 months of continuous selection, 15 hygromycin-resistant lines were recovered. Integration of transgenes into the genome of the transformed protocorms and plantlets were confirmed by GUS histochemical assay and Southern blot hybridization. The transgenic protocorms have gone through propagation for more than 8 months and maintained their transgenic characters. These results indicate that we have established a system for orchid transformation in a relatively high frequency and the transgenes are stably expressed in the transgenic plants.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1006334605947
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  • 24
    Digitale Medien
    Digitale Medien
    Isolation of state transition mutants of Chlamydomonas reinhardtii by fluorescence video imaging (1999)
    Springer
    Photosynthesis research 61 (1999), S. 43-51 
    Details
    ISSN: 1573-5079
    Schlagwort(e): Chlamydomonas reinhardtii ; LHC II phosphorylation ; mutagenesis ; Photosystem II redox control ; state 2 to state 1 transition ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Oxygenic photosynthetic organisms adapt to varying light conditions by changing the distribution of light energy between Photosystem II (PS II) and photosystem I (PS I) during so-called state transitions. To identify the genes involved in this process, we have exploited a simple chlorophyll fluorescence video-imaging technique to screen a library of nuclear mutants of Chlamydomonas reinhardtii for colonies grown on agar plates that are disturbed in their ability to regulate light energy distribution between PS I and PS II. Subsequent modulated fluorescence measurements at room temperature and 77 K fluorescence emission spectra confirmed that 5 mutants (0.025% of total number screened) were defective in state transitions. [32P]orthophosphate phosphorylation experiments in vivo revealed that in one of these mutants, designated stm1, the level of LHC II polypeptide phosphorylation was drastically reduced compared with wild type. Despite WT levels of PS I and PS II, stm1 grew photoautotrophically at reduced rates, compared with WT especially under low light conditions, which is consistent with an important physiological role for state transitions. Our results highlight the feasibility of video imaging in tandem with mutagenesis as a means of identifying the genes involved in controlling state transitions in eukaryotic photosynthetic organisms.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1006229308606
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  • 25
    Digitale Medien
    Digitale Medien
    Simple method for plasmid mediated transformation of different Bacillus species (1999)
    Springer
    Biotechnology techniques 13 (1999), S. 337-340 
    Details
    ISSN: 1573-6784
    Schlagwort(e): Bacillus ; plasmids ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract A simple and easy method for the introduction of plasmid DNA into different species of Bacillus was developed. The method involves the suspension in a transformation buffer of nutrient agar grown cells in their late exponential phase and the addition of unpurified plasmid DNA. Transformants were obtained at a frequency of about 103 to 105 stable transformants per μg of plasmid DNA.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008941007983
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  • 26
    Digitale Medien
    Digitale Medien
    Long-Term Transformation and Redistribution of Potentially Toxic Heavy Metals in Arid-Zone Soils: II. Incubation at the Field Capacity Moisture Content (1999)
    Springer
    Water, air & soil pollution 114 (1999), S. 221-250 
    Details
    ISSN: 1573-2932
    Schlagwort(e): arid-zone soils ; field capacity ; fractionation ; heavy metals ; kinetics ; redistribution ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Energietechnik
    Notizen: Abstract Solid-phase transformation of added Cd, Cu, Cr, Ni, Pb and Zn, in two arid-zone soils incubated in the field capacity moisture regime for one year, were studied. The heavy metals were fractionated into six empirically defined fractions using a selective sequential dissolution (SSD) protocol optimized for arid-zone soils. Each of these fractions was named based on the major soil component targeted for dissolution during the specific SSD step, but it is not assumed that they are mineralogically and chemically totally specific. The transformations of the metals in the two soils incubated at the field capacity regime were compared with those at the moisture saturation regime (Han and Banin, 1997). An initial fast stage of transformation of the soluble metals from the exchangeable (EXC) fraction to the less labile fractions (the carbonate (CARB) fraction for Cd, Pb, Zn, Ni and Cu, and the organic matter (OM) fraction for Cr, and to some extent Cu and Ni) occurred during the fractionation and within one hour after addition. This was followed by a second stage, involving long-term transformation processes of all metals: added Cd was transferred from the EXC into the CARB fraction; added Cr was transferred from the CARB to the OM fraction and Pb was transferred very slowly to the easily reducible oxide (ERO) fraction. Added Cu, Ni and Zn were transferred from the EXC and CARB fractions into the ERO fraction and to some extent OM and RO fractions. In Part I of this series, we reported that during incubation in the saturated moisture regime, Zn and Ni were transferred mainly into the RO and OM fractions. Cadmium, Cr and Pb underwent the same transformation pathways during the slow long-term process, with slightly different rates, in both water regimes. At low levels of addition, the incubated soils moved over one year towards a distribution similar to that of the native soil. At higher levels, the soils still remained removed from the quasi-equilibrium which characterized the native soil, even at the end of one year of incubation.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1005006801650
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  • 27
    Digitale Medien
    Digitale Medien
    Sorption Kinetics and Transformation of DDT in Sediment (1999)
    Springer
    Water, air & soil pollution 110 (1999), S. 57-66 
    Details
    ISSN: 1573-2932
    Schlagwort(e): DDT ; kinetic ; organic pollutant ; sediment ; sorption ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Energietechnik
    Notizen: Abstract The overall objective of this study was to investigate the sorption kinetics of DDT in sediment under similar experimental conditions employed in corresponding toxicity studies for bentic organisms. A batch of aerated Schoonrewoerdse Wiel sediment, initially spiked with DDT, was sampled over a period of seven days. Concentrations of DDT, DDD and DDE were determined in both the solid and the solution phase in the sediment/water system after separation by centrifugation. It was found that the extractable amount of DDT decreased with increasing contact time. This can partly be explained in terms of transformation of DDT into DDD. Furthermore, the present applied extraction procedure seems to be less effective with increasing contact time, indicating an increase in binding strength of DDT with the sediment material. Finally, on the basis of DDT, DDE and DDD concentrations in both the solid phase and the solution phase, partition coefficients were calculated, which appeared to be independent of the contact time. This points at a very rapid equilibrating between DDT in pore water and in the extractable forms adsorbed at the solid phase.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1005087429581
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  • 28
    Digitale Medien
    Digitale Medien
    Environmental Risk Assessment for Pesticides in the Atmosphere; The Results of an International Workshop (1999)
    Springer
    Water, air & soil pollution 115 (1999), S. 5-19 
    Details
    ISSN: 1573-2932
    Schlagwort(e): atmospheric fate ; atmospheric transport ; deposition ; emission ; long-range transport ; pesticides ; registration ; remote area ; risk assessment ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Energietechnik
    Notizen: Abstract The Health Council of the Netherlands organised an international workshop on the fate of pesticides in the atmosphere and possible approaches for their regulatory environmental risk assessment. Approximately forty experts discussed what is currently known about the atmospheric fate of pesticides and major gaps in our understanding were identified. They favoured a tiered approach for assessing the environmental risks of atmospheric dispersion of these chemicals. In the first tier a pesticide's potential for emission during application, as well as its volatilisation potential should be assessed. Estimates of the former should be based on the application method and the formulation, estimates of the latter on a compound's solubility in water, saturated vapour pressure and octanol/water partition coefficient. Where a pesticide's potential for becoming airborne exceeds critical values, it should be subjected to a more rigorous second tier evaluation which considers its toxicity to organisms in non-target areas. This evaluation can be achieved by calculating and comparing a predicted environmental concentration (PEC) and a predicted no-effect concentration (PNEC). By applying an extra uncertainty factor the PNEC can be provisionally derived from standard toxicity data that is already required for the registration of pesticides. Depending on the distance between the source and the reception area, the PEC can be estimated for remote areas using simple dispersion, trajectory type models and for nearby areas using common dispersion models and standard scenarios of pesticide use. A pesticide's atmospheric transport potential is based on factors such as its reaction rate with OH radicals. It should be used to discriminate between those compounds for which only the risks to nearby ecosystems have to be assessed, and those for which the risks to remote ecosystems also have to be determined. The participants were of the opinion that this approach is, in principle, scientifically feasible, although the remaining uncertainties are substantial. Further field and laboratory research is necessary to gain more reliable estimates of the physico-chemical properties of pesticides, to validate and improve environmental fate models and to validate the applicability of standard toxicity data. This will increase both the accuracy of and our confidence in the outcome of the risk assessment.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1005238703698
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  • 29
    Digitale Medien
    Digitale Medien
    Evolution of gene transfer in bacteria (1999)
    Springer
    World journal of microbiology and biotechnology 15 (1999), S. 1-6 
    Details
    ISSN: 1573-0972
    Schlagwort(e): Bacteria ; conjugation ; DNA ; evolution ; gene transfer ; transduction ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract The transfer of genetic information by transformation, conjugation and transduction in bacteria occurs frequently in nature. These diverse gene transfer mechanisms in bacteria are the result of evolution and are not linked to reproduction as in eukaryotic organisms. In this review, gene transfer in bacteria will be considered from an evolutionary perspective.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008830914223
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  • 30
    Digitale Medien
    Digitale Medien
    Biotransformation of cholesterol by Micrococcus species mediated by plasmid DNA (1999)
    Springer
    World journal of microbiology and biotechnology 15 (1999), S. 411-415 
    Details
    ISSN: 1573-0972
    Schlagwort(e): Electroporation ; Micrococcus species ; steroid biotransformation ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract A steroid-biotransforming strain RJ6 was identified as Micrococcus roseus. This bacterium has a 10 kb plasmid pMQV10. Curing mediated through cultivation of the culture with a low concentration (200 ng/ml) of mitomycin C is described. Loss of cholesterol degradation (chol+) and streptomycin resistance (Smr) phenotypes as a consequence of the loss of plasmid indicate the extrachromosomal location of these two genes in this strain. An electroporation procedure was developed for transformation of cured strain of Micrococcus (RJC6) by plasmids. Frequency of greater than 105 transformants/μg DNA was achieved, which is 100-fold higher than the standard transformation procedure that yielded 5.3×103 transformants/μg DNA in the same strain.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1008990910303
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  • 31
    Digitale Medien
    Digitale Medien
    Airflow and temperature distribution in two-dimensional drying bins (1999)
    Springer
    Journal of engineering mathematics 36 (1999), S. 241-254 
    Details
    ISSN: 1573-2703
    Schlagwort(e): flows in porous media ; transformation ; heat transfer ; drying bins ; conformal mapping.
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Mathematik , Technik allgemein
    Notizen: Abstract The design of a drying or cooling store aims to provide an even airflow distribution, when aerated, for preservation purposes. The airflow in some curved bottom bins are studied in this paper. The flow is modelled, using Darcy's law. A generalized Schwarz-Christoffel transformation is employed to reduce the problem of computing streamlines and isobars of airflow to solving a single nonlinear equation for the flow angle along the wall. Corresponding to different bin shapes, a few computed streamlines and isobars of airflow are presented, showing the effect of changing bottom geometries on the air flow. Heat transfer in such bins is also investigated. Based on an analysis of the far field of airflow, finite-height bins are considered. Analytical solutions of the heat conduction equation in terms of streamlines and isobars are obtained.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1004488010532
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  • 32
    Digitale Medien
    Digitale Medien
    Changes in morphology, cytoskeleton, and substrate dependence of proliferation after transfection of immortalized rat embryonic fibroblasts with E7 gene of type 16 human papilloma virus (1999)
    Springer
    Bulletin of experimental biology and medicine 127 (1999), S. 99-102 
    Details
    ISSN: 1573-8221
    Schlagwort(e): human papilloma virus ; transformation ; actin ; fibronectin
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract Transfection of rat embryonic fibroblasts with E7 gene of type 16 human papilloma virus changed the cytoskeleton and cell-cell and cell-matrix interactions in two clones of transformed cells. Cell morphology and substrate-dependent proliferation were also changed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF02432813
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