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
Filter
  • 1990-1994  (7)
  • Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry  (4)
  • Computational Chemistry and Molecular Modeling  (3)
Source
Material
Years
Year
Keywords
  • 1
    Electronic Resource
    Electronic Resource
    Binding of flexible ligands to proteins: Valproic acid and its interaction with cytochrome P450cam (1993)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 48 (1993), S. 161-180 
    Details
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A combined theoretical and experimental study of the binding and interaction of valproic acid (VPA) with the bacterial cytochrome P450cam enzyme and the determination of regio- and stereoselective hydroxylation product distribution was performed. From the experiments, C4—;OH VPA was found to be the predominant hydroxylation product with a small amount of C5—OH VPA formed. The experimental stereoselectivity of hydroxylation was 2R4S 〉 ∼ 2S4R 〉 2R4R 〉 ∼ 2S4S and 2S5 〉 ∼ 2R5. The overall goals of the theoretical study were twofold: (1) to characterize as completely as possible, using energy optimization and molecular dynamics simulations, the interactions of flexible ligands with their target proteins, and (2) to determine the extent to which these results could be used to develop criteria to predict or explain the experimentally observed regio- and stereoselectivity of hydroxylation of the flexible ligands. Among the useful insights into the behavior of flexible ligands upon binding to their traget proteins obtained are (1) a large change in conformation occurs for many conformers of VPA upon binding to P450cam, (2) low- energy conformers of VPA do not necessarily lead to optimum interactions with the target protein, and (3) the most favorable mode of interaction of this flexible ligand with the protein binding site has been identified and found to be a result of strong electrostatic interactions between VPA and both Tyr96 and Asp297. For the study of the hydroxylated VPA products, the challenging aspect of this problem was to determine criteria for weighing the contribution of each of the possible protein-ligand complexes. To this end, various possibilities were examined and compared with the experimental results. No single complex was found to reproduce the observed experimental regio- and stereoselectivity. This result indicates that more than one bioactive form of VPA contributes to its oxidation. Results most consistent with experiment are obtained by using the interaction energy of the protein-ligand complex as a criterion for including its contribution to product formation. Although there are remaining disparities between predicted and observed product distributions, the combined theoretical and experimental effort has led to insights into the modes of interaction of this flexible ligand that lead to its observed product specificity. © 1993 John Wiley & Sons, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560480718
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Premature production of late larval storage proteins in larvae of trichoplusia ni parasitized by euplectrus comstockii (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Archives of Insect Biochemistry and Physiology 26 (1994), S. 97-109 
    Details
    ISSN: 0739-4462
    Keywords: Hymenoptera ; venom ; host hemolymph ; plasma proteins ; regulation ; Chemistry ; Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Investigations were conducted to determine the titer of storage proteins in larvae of the cabbage looper, Trichoplusia ni (Hübner), that were parasitized by the ectoparasitoid Euplectrus comstockii Howard (Hymenoptera: Eulophidae). A gradual increase was noted in the titer of the storage proteins present in the hemolymph of parasitized third and fourth instar larvae and in the hemolymph of isolated thoracic and abdominal tissues of fourth instar larvae. The final amount present in parasitized third and fourth instar larvae was similar to that found in nonparasitized fifth instar larvae. The stimulation of storage proteins in envenomed larvae demonstrates the ability (competence) of early larval stages to produce a gene product that normally occurs in the last larval stadium of the lepidopteran larval host. The gene expression necessary for storage protein production in isolated tissues may be altered by mechanisms separate from inherent developmental processes and the intact endocrine system. © 1994 Wiley-Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United States of America.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/arch.940260204
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Simulations of internal rotation potential energies for substituted ethanes (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Computational Chemistry 11 (1990), S. 743-753 
    Details
    ISSN: 0192-8651
    Keywords: Computational Chemistry and Molecular Modeling ; Biochemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Computer Science
    Notes: Two approaches to the simulation of internal rotation potential energies in substituted ethanes are formulated for general applications. Called the vicinal Fourier coefficient and vicinal pair energy methods, they differ only in form. The latter procedure has the advantage of yielding energy terms that represent pairwise interactions between vicinal substitutents. As numerical examples, the potential energies of ethane and five of its simple methyl and chloro derivatives are employed to simulate the corresponding energies of two higher derivatives of the series. The initial energy data were calculated by the molecular mechanics method (MM2) with geometry optimizations and the ab initio MO procedure (STO-3G) with standard geometries. Results indicate that simulated energies are reasonably accurate for the flexible-rotor model (MM2) and extremely accurate for the rigid-rotor model (STO-3G). Deviations appear to be systematic and may be rationalized on the basis of molecular structure.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcc.540110607
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Partial electrostatic charges for the active center of Cu, Zn superoxide dismutase (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Computational Chemistry 11 (1990), S. 346-350 
    Details
    ISSN: 0192-8651
    Keywords: Computational Chemistry and Molecular Modeling ; Biochemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Computer Science
    Notes: Atomic partial charges for three model systems that mimic the metal-ligand moiety of the active site in the enzyme Cu, Zn superoxide dismutase (SOD) have been calculated at the ab initio level. The model systems include copper and zinc complexes with imidazole, formate and ammonia ligands. The partial charges thus obtained have been incorporated into force fields for molecular simulations. Simulations carried out with these force fields justify the need for specialized charge assignments for the metals and their ligands.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcc.540110309
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Developmental responses of Trichoplusia ni (Lepidoptera: Noctuidae) to parasitism by the ectoparasite Euplectrus plathypenae (Hymenoptera: Eulophidae) (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Archives of Insect Biochemistry and Physiology 13 (1990), S. 83-94 
    Details
    ISSN: 0739-4462
    Keywords: molt arrest ; 20-hydroxyecdysone ; juvenile hormone ; methoprene ; Chemistry ; Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Parasitism by Euplectrus plathypenae inhibits larval-larval ecdysis in Trichoplusia ni by injecting nonparalytic factor(s) into the host during the stinging process via the parasitoid's ovipositor. The parasitized host moves freely, feeds, and gains weight prior to the time of the normal ecdysis but does not molt. Parasitoid development is not required for the expression of molt arrest in the host. Parasitism during the first three fourths of the larval stadium results in molt arrest. Arrestment of molting is independent of 20-hydroxyecdysone and juvenile hormone. The arrestment factor(s) affect the epidermal tissue of the thorax and abdomen in ligated hosts without apparent interaction from other areas of the body. Cuticle and epidermal tissue of parasitized insects do not show signs of apolysis or ecdysis.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/arch.940130108
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    A diapause associated protein of the pink bollworm Pectinophora gossypiella saunders (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Archives of Insect Biochemistry and Physiology 21 (1992), S. 1-11 
    Details
    ISSN: 0739-4462
    Keywords: hemolymph proteins ; diapause protein ; larval diapause ; Chemistry ; Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A diapause associated protein was electrophoretically isolated from the hemolymph of diapausing last instar larvae of the pink bollworm Pectinophora gossypiella. This protein (Mr ∼490,000, glycolipoprotein) was given the name Pectinophora diapause protein (PDP). It is composed of one subunit (Mr 103,000). The concentration of PDP increased dramatically in the hemolymph of diapausing larvae from 17.4% in prediapause (PD) phase to 29.2% in early diapause (ED) phase reaching a level of 38.6% in larval hemolymph of middiapause (MD) phase. The concentrations of total proteins in the hemolymph of active feeding (A), PD, ED, and MD larvae were 69.8, 106.6, 113.3, and 118 mg/ml, respectively, while those in the fat body of the same larvae were 7.1, 7.4, 8.8, and 4.5 mg/g, respectively. In Pectinophora a drop in the concentration of fat body proteins coincided with a corresponding increase in hemolymph proteins, which suggests an active release of protein from the fat body into the hemolymph during the development of diapause. A partial amino acid sequence of pectinophorin showed the first 15 amino acids starting from the amino terminus of the peptide chain: N-ALA-LYS-THR-ILEU-VAL-GLU-ASN-MET-PRO-PRO-THR-PRO-LEU-ASN-ALA-C. © 1992 Wiley-Liss, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/arch.940210102
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    In vitro translation of diapause mRNA from the fat body of active and diapause larvae of the pink bollworm, Pectinophora gossypiella (Saunders) (1993)
    New York, NY [u.a.] : Wiley-Blackwell
    Archives of Insect Biochemistry and Physiology 23 (1993), S. 1-11 
    Details
    ISSN: 0739-4462
    Keywords: diapause protein ; poly(A)+ RNA ; larval diapause ; Chemistry ; Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A diapause associated protein (DAP) (Mr 103,000) was isolated from the hemolymph and fat body of diapausing fourth instar larvae of the pink bollworm Pectinophora gossypiella. The protein has been named Pectinophora diapause protein (PDP). The in vitro translation peptide patterns of total RNA from the fat body of actively feeding fourth instar, wandering, prediapause, early diapause, mid-diapause, and late diapause larvae in rabbit reticulocyte lysates showed the presence of poly (A)+ RNA sequence of PDP. The antigen was immuno-precipitated by polyclonal antiserum. It was concluded that the transcription of the PDP gene in the fat body cells started in the late fourth instar larva and that the expression of this gene was regulated at the level of transcription in the fat body of diapausing larvae. Northern hybridization analysis revealed that wandering fourth instar larvae (diapause individuals) maintain a relatively low level of diapause message (mRNA/2.4 kb) in their fat body cells which may be necessary for the induction of diapause. © 1993 Wiley-Liss, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/arch.940230103
    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...