Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
THE CRYSTAL-STRUCTURE OF A TRIACYLGLYCEROL LIPASE FROM PSEUDOMONAS-CEPACIA REVEALS A HIGHLY OPEN CONFORMATION IN THE ABSENCE OF A BOUND INHIBITOR
Autore:
KIM KK; SONG HK; SHIN DH; HWANG KY; SUH SW;
Indirizzi:
SEOUL NATL UNIV,COLL NAT SCI,DEPT CHEM SEOUL 151742 SOUTH KOREA SEOUL NATL UNIV,COLL NAT SCI,DEPT CHEM SEOUL 151742 SOUTH KOREA
Titolo Testata:
Structure
fascicolo: 2, volume: 5, anno: 1997,
pagine: 173 - 185
SICI:
0969-2126(1997)5:2<173:TCOATL>2.0.ZU;2-D
Fonte:
ISI
Lingua:
ENG
Soggetto:
CANDIDA-RUGOSA LIPASE; INTERFACIAL ACTIVATION; PANCREATIC LIPASE; CHOLESTEROL ESTERASE; GEOTRICHUM-CANDIDUM; LIPOLYTIC ENZYME; TRIAD FORMS; PROTEIN; CLONING; GENE;
Keywords:
LIPASE; PSEUDOMONAS CEPACIA; X-RAY STRUCTURE;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Science Citation Index Expanded
Citazioni:
61
Recensione:
Indirizzi per estratti:
Citazione:
K.K. Kim et al., "THE CRYSTAL-STRUCTURE OF A TRIACYLGLYCEROL LIPASE FROM PSEUDOMONAS-CEPACIA REVEALS A HIGHLY OPEN CONFORMATION IN THE ABSENCE OF A BOUND INHIBITOR", Structure, 5(2), 1997, pp. 173-185

Abstract

Background: Lipases, a family of enzymes which catalyze the hydrolysis of triglycerides, are widely distributed in many organisms. True lipases are distinguished from esterases by the characteristic interfacial activation they exhibit at an oil-water interface. Lipases are one of the most frequently used biocatalysts for organic reactions performed under mild conditions, Their biotechnological applications include food and oil processing and the preparation of chiral intermediates forthe synthesis of enantiomerically pure pharmaceuticals. Recent structural studies on several lipases have provided some clues towards understanding the mechanisms of hydrolytic activity, interfacial activation, and stereoselectivity. This study was undertaken in order to providestructural information on bacterial lipases, which is relatively limited in comparison to that on the enzymes from other sources. Results: We have determined the crystal structure of a triacylglycerol lipase from Pseudomonas cepacia (Pet) in the absence of a bound inhibitor using X-ray crystallography, The structure shows the lipase to contain an alpha/beta-hydrolase fold and a catalytic triad comprising of residuesSer87, His286 and Asp264. The enzyme shares several structural features with homologous lipases from Pseudomonas glumae (PgL) and Chromobacterium viscosum (CvL), including a calcium-binding site, The present structure of Pet reveals a highly open conformation with a solvent-accessible active site, This is in contrast to the structures of PgL and Pet in which the active site is buried under a closed or partially opened 'lid', respectively. Conclusions: Pet exhibits some structural features found in other lipases. The presence of the Ser-His-Asp catalytictriad, an oxyanion hole, and the opening of a helical lid suggest that this enzyme shares the same mechanisms of catalysis and interfacial activation as other lipases. The highly open conformation observed in this study is likely to reflect the activated form of the lipase at anoil-water interface. The structure suggests that the interfacial activation of bacterial lipases involves the reorganization of secondary structures and a large movement of the lid to expose the active site, This is similar to the mechanism described for other well characterizedfungal and mammalian lipases.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 11/07/20 alle ore 07:53:06