Autoproteolytic and Catalytic Mechanisms for the β-Aminopeptidase BapA—A Member of the Ntn Hydrolase Family
摘要:
The beta-aminopeptidase BapA from Sphingosinicella xenopeptidilytica belongs to the N-terminal nucleophile (Ntn) hydrolases of the DmpA-like family and has the unprecedented property of cleaving N-terminal beta-amino acid residues from peptides. We determined the crystal structures of the native (alpha beta)(4) heterooctamer and of the 153 kDa precursor homotetramer at a resolution of 1.45 and 1.8 angstrom, respectively. These structures together with mutational analyses strongly support mechanisms for autoproteolysis and catalysis that involve residues Ser250, Ser288, and Glu290. The autoproteolytic mechanism is different from the one so far described for Ntn hydrolases. The structures together with functional data also provide insight into the discriminating features of the active site cleft that determine substrate specificity.
Novel enzymatic substrates for detecting pseudomonas aeruginosa, compositions containing same and method for detecting said species
申请人:——
公开号:US20030044877A1
公开(公告)日:2003-03-06
This invention concerns an enzyme substrate consisting of a target part and a marker part, hydrolysis of the substrate leading to separation of the target part from the marker part, and said target part being specific for the enzyme activity being assayed. It also concerns a formulation containing at least one such substrate, and a method for detecting the bacterial species
Pseudomonas aeruginosa.
The target part of the substrate is specific for &bgr;-alanine aminopeptidase activity and the marker part is a compound which reveals whether a hydrolysis reaction has taken place or not.
The invention is particularly applicable in the field of diagnosis.
Procédés, compositions et substrats enzymatiques pour la détection de pseudomonas aeruginosa
申请人:BIOMERIEUX SA
公开号:EP1621530A1
公开(公告)日:2006-02-01
La présente invention concerne un substrat enzymatique constitué d'une partie cible et d'une partie marqueur, l'hydrolyse du substrat permettant la séparation de la partie cible et de la partie marqueur, ladite partie cible caractérisant l'activité enzymatique recherchée. Elle concerne également une composition contenant au moins un tel substrat, ainsi qu'un procédé de détection de l'espèce bactérienne Pseudomonas aeruginosa.
La partie cible du substrat permet de révéler une activité enzymatique β-alanine aminopeptidase et la partie marqueur est une molécule révélant la réaction d'hydrolyse.
L'invention trouve une application préférentielle dans le domaine du diagnostic.
NOUVEAUX SUBSTRATS ENZYMATIQUES POUR LA DETECTION DE PSEUDOMONAS AERUGINOSA
申请人:Biomerieux S.A.
公开号:EP1235927A2
公开(公告)日:2002-09-04
MILIEU DE DÉTECTION ET/OU D'IDENTIFICATION DE BACTÉRIES
申请人:BIOMERIEUX
公开号:EP2111460A2
公开(公告)日:2009-10-28
MEDIUM FOR THE DETECTION AND/OR IDENTIFICATION OF BACTERIA
申请人:Casse Marine
公开号:US20100062466A1
公开(公告)日:2010-03-11
A detection medium including
a substrate for a metabolic activity specific for a group of Gram-negative bacteria
a beta-glucosidase or cellobiosidase substrate
and a beta-glucosidase or cellobiosidase inducer. The inducer is a carbohydrate constituted of a carbohydrate linked in the β-position to glucose, or a carbohydrate with a β glucoside subunit, preferably selected from cellobiose, cellulose, starch, cellotriose and trehalose.