02032nas a2200253 4500008004100000022001400041245014000055210006900195260005700264300001400321490000700335520111700342653001301459653002001472653001401492653001801506653001701524653002301541100002901564700001601593700001501609700002401624856013001648 2012 eng d a1590-426100aCharacterization of a new bacillus cereus ATUAVP1846 strain producing penicillin V acylase, and optimization of fermentation parameters0 aCharacterization of a new bacillus cereus ATUAVP1846 strain prod a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcSEP a1287-12930 v623 a

Penicillin acylases are involved chiefly in the industrial production of semisynthetic penicillins, which remain the most widely used group of antibiotics. We have isolated a new bacterial strain ATUAVP1846 that produces penicillin V acylase (PVA). Phylogenetic analysis using 16S rRNA sequencing showed 99.37% homology with Bacillus cereus. Maximum PVA production was observed with B. cereus ATUAVP1846 at 30A degrees C, pH 7 after 24 h fermentation time under submerged conditions. Highest enzyme productivity was achieved using sucrose as carbon source, and tryptone and ammonium hydrogen phosphate as nitrogen sources. Minimal medium containing 0.4% glucose and 0.3% ammonium hydrogen phosphate was found to be optimal for maximum PVA production from B. cereus ATUAVP1846. The crude enzyme from B. cereus ATUAVP1846 was partially purified using ammonium sulfate fractionation and showed highest enzymatic activity in the hydrolysis of penicillin V at 40A degrees C and pH 6. The crude enzyme preparation also showed unique substrate specificity, preferring ampicillin and cephalexin over penicillin V.

10a16S rRNA10aBacillus cereus10aisolation10aNtn hydrolase10aOptimization10aPenicillin acylase1 aSunder, Avinash, Vellore1 aKumar, Atul1 aNaik, Neha1 aPundle, Archana, V. uhttp://library.ncl.res.in/content/characterization-new-bacillus-cereus-atuavp1846-strain-producing-penicillin-v-acylase-and-002534nas a2200265 4500008004100000022001400041245013800055210006900193260000800262300001400270490000800284520159300292653003701885653001801922653001701940653002401957653002101981100002902002700002202031700002602053700002402079700001402103700002002117856013102137 2017 eng d a0175-759800aPenicillin V acylases from gram-negative bacteria degrade N-acylhomoserine lactones and attenuate virulence in Pseudomonas aeruginosa0 aPenicillin V acylases from gramnegative bacteria degrade Nacylho cMAR a2383-23950 v1013 a

Virulence pathways in gram-negative pathogenic bacteria are regulated by quorum sensing mechanisms, through the production and sensing of N-acylhomoserine lactone (AHL) signal molecules. Enzymatic degradation of AHLs leading to attenuation of virulence (quorum quenching) could pave the way for the development of new antibacterials. Penicillin V acylases (PVAs) belong to the Ntn hydrolase superfamily, together with AHL acylases. PVAs are exploited widely in the pharmaceutical industry, but their role in the natural physiology of their native microbes is not clearly understood. This report details the characterization of AHL degradation activity by homotetrameric PVAs from two gram-negative plant pathogenic bacteria, Pectobacterium atrosepticum (PaPVA) and Agrobacterium tumefaciens (AtPVA). Both the PVAs exhibited substrate specificity for degrading long-chain AHLs. Exogenous addition of these enzymes into Pseudomonas aeruginosa greatly diminished the production of elastase and pyocyanin and biofilm formation and increased the survival rate in an insect model of acute infection. Subtle structural differences in the PVA active site that regulate specificity for acyl chain length have been characterized, which could reflect the evolution of AHL-degrading acylases in relation to the environment of the bacteria that produce them and also provide strategies for enzyme engineering. The potential for using these enzymes as therapeutic agents in clinical applications and a few ideas about their possible significance in microbial physiology have also been discussed.

10aN-acylhomoserine lactone acylase10aNtn hydrolase10apathogenesis10aPenicillin Vacylase10aQuorum quenching1 aSunder, Avinash, Vellore1 aUtari, Putri, Dwi1 aRamasamy, Sureshkumar1 avan Merkerk, Ronald1 aQuax, Wim1 aPundle, Archana uhttp://library.ncl.res.in/content/penicillin-v-acylases-gram-negative-bacteria-degrade-n-acylhomoserine-lactones-and-attenuate02146nas a2200193 4500008004100000022001400041245014800055210006900203260000900272300001600281490000600297520140000303100002101703700002901724700003001753700002601783700002001809856012301829 2020 eng d a2470-134300aProcess development for 6-aminopenicillanic acid production using lentikats-encapsulated escherichia coli cells expressing penicillin V acylase0 aProcess development for 6aminopenicillanic acid production using cNOV  a28972-289760 v53 a

Penicillin V acylase (PVA, EC 3.5.1.11) hydrolyzes the side chain of phenoxymethylpenicillin (Pen V) and finds application in the manufacture of the pharmaceutical intermediate 6-aminopenicillanic acid (6-APA). Here, we report the scale-up of cultivation of Escherichia coli whole cells expressing a highly active PVA from Pectobacterium atrosepticum and their encapsulation in polyvinyl alcohol-poly(ethylene glycol) Lentikats hydrogels. A biocatalytic process for the hydrolysis of 2% (w/v) Pen V was set up in a 2 L reactor using the Lentikats-immobilized whole cells, with a customized setup to enable continuous downstream processing of the reaction products. The biocatalytic reaction afforded complete conversion of Pen V for 10 reaction cycles, with an overall 90% conversion up to 50 cycles. The bioprocess was further scaled up to the pilot-scale at 10 L, enabling complete conversion of Pen V to 6-APA for 10 cycles. The 6-APA and phenoxy acetic acid products were recovered from downstream processing with isolated yields of 85-90 and 87-92%, respectively. Immobilization in Lentikats beads improved the stability of the whole cells on storage, maintaining 90-100% activity and similar conversion efficiency after 3 months at 4 degrees C. The robust PVA biocatalyst can be employed in a continuous process to provide a sustainable route for bulk 6-APA production from Pen V.

1 aSawant, Amol, M.1 aSunder, Avinash, Vellore1 aVamkudoth, Koteswara, Rao1 aRamasamy, Sureshkumar1 aPundle, Archana uhttp://library.ncl.res.in/content/process-development-6-aminopenicillanic-acid-production-using-lentikats-encapsulated02160nas a2200265 4500008004100000022001400041245012500055210006900180260000800249300001200257490000800269520124900277653001601526653002901542653001401571653001301585653002701598100002701625700001901652700002901671700002101700700002101721700002601742856012601768 2020 eng d a0300-908400aStructural and enzymatic analysis of a dimeric cholylglycine hydrolase like acylase active on N-acyl homoserine lactones0 aStructural and enzymatic analysis of a dimeric cholylglycine hyd cOCT a108-1160 v1773 a

The prevalence of substrate cross-reactivity between AHL acylases and beta-lactam acylases provides a glimpse of probable links between quorum sensing and antibiotic resistance in bacteria. Both these enzyme classes belong to the N-terminal nucleophile (Ntn)-hydrolase superfamily. Penicillin V acylases alongside bile salt hydrolases constitute the cholylglycine hydrolase (CGH) group of the Ntn-hydrolase superfamily. Here we report the ability of two acylases, Slac1 and Slac2, from the marine bacterium Shewanella loihica PV4 to hydrolyze AHLs. Three-dimensional structure of Slac1 reveals the conservation of the Ntn hydrolase fold and CGH active site, making it a unique CGH exclusively active on AHLs. Slac1homologs phylogenetically cluster separate from reported CGHs and AHL acylases, thereby representing a functionally distinct sub-class of CGH that might have evolved as an adaptation to the marine environment. We hypothesize that Slac1 could provide the structural framework for understanding this subclass, and further our understanding of the evolutionary link between AHL acylases and beta-lactam acylases. (C) 2020 Elsevier B.V. and Societe Francaise de Biochimie et Biologie Moleculaire (SFBBM). All rights reserved.

10aAHL acylase10aCholyolglycine hydrolase10aHomodimer10aNtn-fold10aShewanella loihica-PV41 aPhilem, Pushparani, D.1 aYadav, Yashpal1 aSunder, Avinash, Vellore1 aGhosh, Deepanjan1 aPrabhune, Asmita1 aRamasamy, Sureshkumar uhttp://library.ncl.res.in/content/structural-and-enzymatic-analysis-dimeric-cholylglycine-hydrolase-acylase-active-n-acyl