01979nas a2200217   4500008004100000022001400041245016600055210006900221260010300290300001600393490000800409520106400417100001801481700002501499700002101524700002401545700002001569700002401589700001901613856012901632       2006                        eng d  a0021-925800aStructural and functional analysis of a conjugated bile salt hydrolase from Bifidobacterium longum reveals an evolutionary relationship with penicillin V acylase0 aStructural and functional analysis of a conjugated bile salt hyd  a9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USAbAMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INCcOCT  a32516-325250 v2813 a<p>Bile salt hydrolase (BSH) is an enzyme produced by the intestinal microflora that catalyzes the deconjugation of glycine- or taurine-linked bile salts. The crystal structure of BSH reported here from Bifidobacterium longum reveals that it is a member of N-terminal nucleophil hydrolase structural superfamily possessing the characteristic alpha beta beta alpha tetra-lamellar tertiary structure arrangement. Site-directed mutagenesis of the catalytic nucleophil residue, however, shows that it has no role in zymogen processing into its corresponding active form. Substrate specificity was studied using Michaelis-Menten and inhibition kinetics and fluorescence spectroscopy. These data were compared with the specificity profile of BSH from Clostridium perfrigens and pencillin V acylase from Bacillus sphaericus, for both of which the three-dimensional structures are available. Comparative analysis shows a gradation in activity toward common substrates, throwing light on a possible common route toward the evolution of pencillin V acylase and BSH.</p>1 aKumar, Suresh1 aBrannigan, James, A.1 aPrabhune, Asmita1 aPundle, Archana, V.1 aDodson, Guy, G.1 aDodson, Eleanor, J.1 aSuresh, C., G.  uhttp://library.ncl.res.in/content/structural-and-functional-analysis-conjugated-bile-salt-hydrolase-bifidobacterium-longum-001921nas a2200265   4500008004100000022001400041245011800055210006900173260009500242300001200337490000800349520092800357653002401285653001201309653002301321653001501344653001901359653002301378100002901401700002601430700001901456700002401475700002601499856013001525       2013                        eng d  a0006-291X00aStructural modelling of substrate binding and inhibition in penicillin V acylase from pectobacterium atrosepticum0 aStructural modelling of substrate binding and inhibition in peni  a525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USAbACADEMIC PRESS INC ELSEVIER SCIENCEcAUG  a538-5430 v4373 a<p>Penicillin V acylases (PVAs) and bile salt hydrolases (BSHs) have considerable sequence and structural similarity; however, they vary significantly in their substrate specificity. We have identified a PVA from a Gram-negative organism, Pectobacterium atrosepticum (PaPVA) that turned out to be a remote homolog of the PVAs and BSHs reported earlier. Even though the active site residues were conserved in PaPVA it showed high specificity towards penV and interestingly the penV acylase activity was inhibited by bile salts. Comparative modelling and docking studies were carried out to understand the structural differences of the binding site that confer this characteristic property. We show that PaPVA exhibits significant differences in structure, which are in contrast to those of known PVAs and such enzymes from Gram-negative bacteria require further investigation. (C) 2013 Elsevier Inc. All rights reserved.</p>10aBile salt hydrolase10adocking10aHomology modelling10aInhibition10aPectobacterium10aPenicillin acylase1 aAvinash, Vellore, Sunder1 aPanigrahi, Priyabrata1 aSuresh, C., G.1 aPundle, Archana, V.1 aRamasamy, Sureshkumar  uhttp://library.ncl.res.in/content/structural-modelling-substrate-binding-and-inhibition-penicillin-v-acylase-pectobacterium-0