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Titolo:
STRUCTURAL BASIS OF THE CHIRAL SELECTIVITY OF PSEUDOMONAS-CEPACIA LIPASE
Autore:
LANG DA; MANNESSE MLM; DEHAAS GH; VERHEIJ HM; DIJKSTRA BW;
Indirizzi:
UNIV GRONINGEN,BIOPHYS CHEM LAB,NIJENBORGH 4 NL-9747 AG GRONINGEN NETHERLANDS UNIV GRONINGEN,BIOPHYS CHEM LAB NL-9747 AG GRONINGEN NETHERLANDS UNIV GRONINGEN,BIOSON RES INST NL-9747 AG GRONINGEN NETHERLANDS UNIV UTRECHT,CBLE,DEPT ENZYMOL & PROT ENGN NL-3508 TC UTRECHT NETHERLANDS
Titolo Testata:
European journal of biochemistry
fascicolo: 2, volume: 254, anno: 1998,
pagine: 333 - 340
SICI:
0014-2956(1998)254:2<333:SBOTCS>2.0.ZU;2-P
Fonte:
ISI
Lingua:
ENG
Soggetto:
CANDIDA-RUGOSA LIPASE; INTERFACIAL ACTIVATION; TRIACYLGLYCEROL LIPASE; PANCREATIC LIPASE; MICROBIAL LIPASES; CRYSTAL-STRUCTURE; TRIAD FORMS; PHOSPHONATE; COMPLEX; CRYSTALLIZATION;
Keywords:
CRYSTAL STRUCTURE; TRANSITION-STATE ANALOG; ENANTIOSELECTIVITY; LIPASE; STEREOSPECIFICITY;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
43
Recensione:
Indirizzi per estratti:
Citazione:
D.A. Lang et al., "STRUCTURAL BASIS OF THE CHIRAL SELECTIVITY OF PSEUDOMONAS-CEPACIA LIPASE", European journal of biochemistry, 254(2), 1998, pp. 333-340

Abstract

To investigate the enantioselectivity of Pseudomonas cepacia lipase, inhibition studies were performed with S-c-and S-p)-1,2-dialkylcarbamoylglycero-3-O-p-nitrophenyl alkylphosphonates of different alkyl chainlengths. P. cepacia lipase was most rapidly inactivated by S-p)-1,2-dioctylcarbamoylglycero-3-O-p-nitrophenyl octylphosphonate (R-c-trioctyl) with an inactivation half-time of 75 min, while that for the S-p)-1,2-dioctylcarbamoylglycero-3-O-p-nitrophenyl octyl-phosphonate (S-c-trioctyl) compound was 530 min. X-ray structures were obtained of P. cepacia lipase after reaction with R-c-trioctyl to 0.29-nm resolution at pH 4 and covalently modified with S-p)-1,2-dibutylcarbamoylglycero-3-O-p-nitrophenyl butyl-phosphonate (R-c-tributyl) to 0.175-nm resolutionat pH 8.5. The three-dimensional structures reveal that both triacylglycerol analogues had reacted with the active-site Ser87, forming a covalent complex. The bound phosphorus atom shows the same chirality (S-p) in both complexes despite the use of a racemic (R-p,S-p) mixture atthe phosphorus atom of the triacylglycerol analogues. In the structure of R-c-tributyl-complexed P. cepacia lipase, the diacylglycerol moiety has been lost due to an aging reaction, and only the butyl phosphonate remains visible in the electron density. In the R-c-trioctyl complex the complete inhibitor is clearly defined; it adopts a bent tuning fork conformation. Unambiguously, four binding pockets for the triacylglycerol could be detected: an oxyanion hole and three pockets which accommodate the sn-l, sn-2, and sn-3 fatty acid chains. Van der Waals' interactions are the main forces that keep the radyl groups of the triacylglycerol analogue in position and, in addition, a hydrogen bond tothe carbonyl oxygen of the sn-2 chain contributes to fixing the position of the inhibitor.

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Documento generato il 27/11/20 alle ore 02:14:19