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Titolo:
Computer-aided molecular modeling of the enantioselectivity of Pseudomonascepacia lipase toward gamma- and delta-lactones
Autore:
Hwang, BY; Scheib, H; Pleiss, J; Kim, BG; Schmid, RD;
Indirizzi:
Univ Stuttgart, Inst Tech Biochem, D-70569 Stuttgart, Germany Univ Stuttgart Stuttgart Germany D-70569 hem, D-70569 Stuttgart, Germany Seoul Natl Univ, Div Chem Engn, Lab Mol Biotechnol & Biomat, Seoul 151742,South Korea Seoul Natl Univ Seoul South Korea 151742 iomat, Seoul 151742,South Korea Seoul Natl Univ, Inst Mol Biol & Genet, Seoul 151742, South Korea Seoul Natl Univ Seoul South Korea 151742 enet, Seoul 151742, South Korea
Titolo Testata:
JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC
fascicolo: 1-3, volume: 10, anno: 2000,
pagine: 223 - 231
SICI:
1381-1177(20000904)10:1-3<223:CMMOTE>2.0.ZU;2-9
Fonte:
ISI
Lingua:
ENG
Soggetto:
RHIZOPUS-ORYZAE LIPASE; PSEUDOMONAS SP KWI-56; RESOLUTION; HYDROLYSIS; EXPRESSION; CLONING; GENES;
Keywords:
molecular modeling; Pseudomonas cepacia lipase; enantioselectivity; gamma-lactone; delta-lactone;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
15
Recensione:
Indirizzi per estratti:
Indirizzo: Schmid, RD Univ Stuttgart, Inst Tech Biochem, Allmandring 31, D-70569 Stuttgart, Germany Univ Stuttgart Allmandring 31 Stuttgart Germany D-70569 ermany
Citazione:
B.Y. Hwang et al., "Computer-aided molecular modeling of the enantioselectivity of Pseudomonascepacia lipase toward gamma- and delta-lactones", J MOL CAT B, 10(1-3), 2000, pp. 223-231

Abstract

Computer-aided molecular modeling was performed to investigate the experimentally determined enantioselectivities of Pseudomonas cepacia Lipase (PCL)toward various saturated gamma- and delta-lactones. Experimental data indicated that PCL preferentially hydrolyzes the (R)-enantiomers of both types of substrates. Interactions between the non-polar aliphatic alkyl chain of the (S)-enantiomers and the polar side chain of residue Y29 were identifiedto mediate enantioselectivity. Upon binding, the tyrosine was displaced, thus initiating a cascade of local geometry changes which led to the breakdown of the essential H-bond network at the active site H286. The lactone ring of the (S)-delta-enantiomers further added to this process, since it was forced into an unfavorable position by repulsion from Y29, directly affecting the position of H286. In contrast, the respective (R)-enantiomers fit without distorting side chains essential for catalysis in the binding pocket of PCL. In delta-lactones, the stereocenter was located close to the imidazole ring of H286, suggesting a more intense interaction with H286 as compared to gamma-lactones. The length of the aliphatic chain adjacent to the stereocenter also affected the enantiopreference toward hydrolysis of delta-lactones, while for gamma-lactones, the enantioselectivity did not significantly change with increasing alkyl chain length. In the cases of (S)-delta-octa- and (S)-delta-nonalactone, two alternative possible binding modes were examined, indicating that the respective substrate resolutions led to poor enantioselectivity as compared to the longer-chain delta-lactone substrates. (C) 2000 Elsevier Science B.V. All rights reserved.

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Documento generato il 29/11/20 alle ore 16:26:59