Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Ralstonia metallidurans, a bacterium specifically adapted to toxic metals: towards a catalogue of metal-responsive genes (2003)
    Oxford, UK : Blackwell Publishing Ltd
    FEMS microbiology reviews 27 (2003), S. 0 
    Details
    ISSN: 1574-6976
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Ralstonia metallidurans, formerly known as Alcaligenes eutrophus and thereafter as Ralstonia eutropha, is a β-Proteobacterium colonizing industrial sediments, soils or wastes with a high content of heavy metals. The type strain CH34 carries two large plasmids (pMOL28 and pMOL30) bearing a variety of genes for metal resistance. A chronological overview describes the progress made in the knowledge of the plasmid-borne metal resistance mechanisms, the genetics of R. metallidurans CH34 and its taxonomy, and the applications of this strain in the fields of environmental remediation and microbial ecology. Recently, the sequence draft of the genome of R. metallidurans has become available. This allowed a comparison of these preliminary data with the published genome data of the plant pathogen Ralstonia solanacearum, which harbors a megaplasmid (of 2.1 Mb) carrying some metal resistance genes that are similar to those found in R. metallidurans CH34. In addition, a first inventory of metal resistance genes and operons across these two organisms could be made. This inventory, which partly relied on the use of proteomic approaches, revealed the presence of numerous loci not only on the large plasmids pMOL28 and pMOL30 but also on the chromosome. It suggests that metal-resistant Ralstonia, through evolution, are particularly well adapted to the harsh environments typically created by extreme anthropogenic situations or biotopes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1016/S0168-6445(03)00045-7
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Two-component regulatory system involved in transcriptional control of heavy-metal homoeostasis in Alcaligenes eutrophus (1997)
    Oxford BSL : Blackwell Science Ltd
    Molecular microbiology 23 (1997), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: The czc determinant, which mediates resistance to Co2+, Zn2+ and Cd2+ in Alcaligenes eutrophus CH34 by cation efflux, is regulated by a two-component regulatory system composed of the sensor histidine kinase CzcS and the response activator CzcR (in addition to other components previously described). Regulatory genes are arranged in an upstream regulatory region (URR) and a downstream regulatory region (DRR). Transcription of czcCBA and of the URR was regulated by heavy-metal cations. DNA sequencing of the region downstream of czcD revealed the presence of the czcR and czcS genes which together with czcD form the DRR. Regulation of the DRR was studied with a czcD::lacZ translational fusion and a czcS::lux transcriptional fusion. Expression of both genes is also regulated by heavy metals. The genes of the URR yielded three mRNAs of approx. 1200, 500 and 200 nucleotides, respectively. The genes czcCBA for the cation/proton antiporter CzcCBA were transcribed by one operon as a transcript of 6200 nucleotides.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.1997.d01-1866.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Evidence that Ralstonia eutropha (Alcaligenes eutrophus) contains a functional homologue of the Ralstonia solanacearum Phc cell density sensing system (2000)
    Oxford, UK : Blackwell Science Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: In the phytopathogen Ralstonia (Pseudomonas) solanacearum, control of many virulence genes is partly mediated by the Phc cell density sensing system. Phc uses a novel self-produced signal molecule [3-hydroxypalmitic acid methyl ester (3-OH PAME)], an atypical two-component system (PhcS/PhcR), and a LysR-type activator (PhcA) to regulate a reversible switching between two different physiological states. While Phc is present in most R. solanacearum strains, it is apparently absent from other pseudomonad plant pathogens and prokaryotic genomes that have been sequenced. Here, we report discovery of a phcA orthologue in the non-pathogenic, facultative chemolithoautotroph Ralstonia eutropha (Alcaligenes eutrophus) that fully complements R. solanacearum phcA mutants. We also demonstrate that some R. eutropha produce an extracellular factor that complements R. solanacearum mutants deficient in production of the 3-OH PAME signal molecule that controls phcA. Additionally, Southern blot hybridization analysis suggested that R. eutropha harbours other Phc components, such as PhcB (a biosynthetic enzyme for 3-OH PAME) and PhcS (a 3-OH PAME-responsive sensor kinase). Analysis of a phcA-null mutant of R. eutropha showed that phcA (and probably Phc) positively activates motility, in contrast to R. solanacearum where it represses motility. Similarly, the R. eutropha phcA mutant was unaffected in siderophore production, whereas inactivation of phcA in R. solanacearum increases siderophore production. Although our data strongly suggest that R. eutropha has a functional Phc-like system and support the phylogeny of Ralstonia, it implies that Phc may have a different physiological and ecological function in R. eutropha.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02131.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Colonisation of poplar trees by gfp expressing bacterial endophytes (2004)
    Oxford, UK : Blackwell Publishing Ltd
    FEMS microbiology ecology 48 (2004), S. 0 
    Details
    ISSN: 1574-6941
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: With the exception of nitrogen fixing bacteria, there is little known about the colonisation patterns or population sizes of bacterial endophytes in deciduous trees. This study describes the isolation, identification, construction and re-colonisation patterns of three green fluorescent protein(gfp):kanamycinR labelled bacterial endophytes when re-introduced into poplar trees, their original host plant. Two of these endophytes showed considerable colonisation in the roots and stems of inoculated plants. gfp expressing cells of all three strains were observed to colonise the xylem tissue of the root. All three strains proved to be efficient rhizosphere colonisers, supporting the theory that the rhizosphere can serve as a source of bacterial endophytes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1016/j.femsec.2003.12.009
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Liposome-enhanced transformation of streptococcus lactis and plasmid transfer by intergeneric protoplast fusion of streptococcus lactis and bacillus subtilis (1988)
    Oxford, UK : Blackwell Publishing Ltd
    FEMS microbiology letters 49 (1988), S. 0 
    Details
    ISSN: 1574-6968
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Abstract An efficient protoplast transformation system and a procedure of plasmid transfer by means of protoplast fusion is described for Streptococcus lactis. Protoplasts of S. lactis IL1403 and S. lactis MG1363 were transformed by pGK12 [2.9 MDa erythromycin resistance (Emr)] with an efficiency of 3 × 105 transformants per μg plasmid DNA. This high efficiency was obtained by the inclusion in the transformation mixture of liposomes composed of cardiolipin and phosphatidyl choline in a molar ratio of 1 to 6 in the presence of 22.5% polyethylene glycol (PEG). This paper also reports an efficient plasmid transfer method between lactic and streptococci and Bacillus subtilis by means of protoplast fusion. When S. lactis and B. lactis protoplasts undergo fusion mediated by exposure to 37.5% polyethylene glycol, plasmid pGKV21 (3.2 MDa; Emr) was transfered from one host to the other with a frequency of 10−3−10−5 transformants per regenerating recipient protoplast.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1574-6968.1988.tb02751.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Engineered endophytic bacteria improve phytoremediation of water-soluble, volatile, organic pollutants (2004)
    [s.l.] : Nature Publishing Group
    Nature biotechnology 22 (2004), S. 583-588 
    Details
    ISSN: 1546-1696
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: [Auszug] Phytoremediation of highly water soluble and volatile organic xenobiotics is often inefficient because plants do not completely degrade these compounds through their rhizospheres. This results in phytotoxicity and/or volatilization of chemicals through the leaves, which can cause additional ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/nbt960
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Theczc operon ofAlcaligenes eutrophus CH34: from resistance mechanism to the removal of heavy metals (1995)
    Springer
    Journal of industrial microbiology and biotechnology 14 (1995), S. 142-153 
    Details
    ISSN: 1476-5535
    Keywords: Soil bacteria ; Alcaligenes ; Plasmid ; Cadmium ; Metal resistance ; Cation efflux ; Gene fusion ; Bioprecipitation ; Bioreactor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary The plasmid-borneczc operon ensures for resistance to Cd2+, Zn2+ and Co2+ ions through a tricomponent export pathway and is associated to various conjugative plasmids ofA. eutrophus strains isolated from metal-contaminated industrial areas. Theczc region of pMOL30 was reassessed especially for the segments located upstream and downstream the structural genesczc CBA. In cultures grown with high concentrations of heavy metals,czc-mediated efflux of cations is followed by a process of metal bioprecipitation. These observations led to the development of bioreactors designed for the removal of heavy metals from polluted effluents.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01569896
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Chemical and Biological Parameters as Tools to Evaluate and Improve Heavy Metal Phytoremediation (2000)
    Springer
    Bioscience reports 20 (2000), S. 239-258 
    Details
    ISSN: 1573-4935
    Keywords: heavy metals ; phytoremediation ; bioremediation ; bioavailability ; chemical availability ; soil microorganisms ; plant-microbe interactions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In this review, chemical and biological parameters are discussed thatstrongly influence the speciation of heavy metals, their availability tobiological systems and, consequently, the possibilities to usebioremediation as a cleanup tool for heavy metal polluted sites. In orderto assess heavy metal availability, a need exists for rapid, cost-effectivesystems that reliably predict this parameter and, based on this, thefeasibility of using biological remediation techniques for site managementand restoration. Special attention is paid to phytoremediation as anemerging technology for stabilization and remediation of heavy metalpollution. In order to improve phytoremediation of heavy metal pollutedsites, several important points relevant to the process have to beelucidated. These include the speciation and bioavailability of the heavymetals in the soil determined by many chemical and biological parameters,the role of plant-associated soil microorganisms and fungi inphytoremediation, and the plants. Several options are described how plant-associated soil microorganisms canbe used to improve heavy metal phytoremediation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1026436806319
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Identification of a partition and replication region in theAlcaligenes eutrophus megaplasmid pMOL28 (1996)
    Springer
    Molecular genetics and genomics 250 (1996), S. 169-179 
    Details
    ISSN: 1617-4623
    Keywords: Alcaligenes eutrophus ; pMOL28 ; Plasmid replication ; Plasmid partition ; Plasmid stability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A 4.64 kb region of the 180 kb heavy metal resistance plasmid pMOL28 ofAlcaligenes eutrophus CH34, previously shown to be able to replicate autonomously, was sequenced and analyzed. Three genes involved in plasmid maintenance were identified:parA28 andparB28 are involved in plasmid partitioning and stability, whilerepA28 encodes a protein required for replication. In addition to theparAB28 genes, a third locus,parS28, required in cis for active partitioning was identified. TheparABS28 locus of pMOL28 shows strong similarity in organization to thesop, par andrep regions, respectively, of theEscherichia coli F-factor, theE. coli P1 and P7 prophages, and theAgrobacterium pTiB6S3 and pRiA4b plasmids. The ParAB28 proteins of pMOL28 also show similarity to the proteins encoded by two conserved open reading frames present in the replication regions of thePseudomonas putida andBacillus subtilus chromosomes. The functionality of the pMOL28par region was examined by performing stability and incompatibility tests between pMOL28 and pMOL846 or pMOL850, which contain the 4.64EcoRI replicon fragment of pMOL28, cloned in opposite orientations into pSUP202, which is itself unable to replicate inA. eutrophus. The RepA28 replication protein showed similarity to the RepL protein of P1, which is required for lytic replication of thisE. coli phage. The replication origin of pMOL28,oriV28, seems to be located within therepA28 coding region, and pMOL28 replication may depend on transcriptional activation oforiV28.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02174176
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...