@article { ISI:000307537300043, title = {Characterization of a new bacillus cereus ATUAVP1846 strain producing penicillin V acylase, and optimization of fermentation parameters}, journal = {Annals of Microbiology}, volume = {62}, number = {3}, year = {2012}, month = {SEP}, pages = {1287-1293}, publisher = {SPRINGER}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

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.

}, keywords = {16S rRNA, Bacillus cereus, isolation, Ntn hydrolase, Optimization, Penicillin acylase}, issn = {1590-4261}, doi = {10.1007/s13213-011-0374-7}, author = {Sunder, Avinash Vellore and Kumar, Atul and Naik, Neha and Pundle, Archana V.} } @article {45766, title = {Penicillin V acylases from gram-negative bacteria degrade N-acylhomoserine lactones and attenuate virulence in Pseudomonas aeruginosa}, journal = {Applied Microbiology and Biotechnology}, volume = {101}, year = {2017}, month = {MAR}, pages = {2383-2395}, type = {Article}, abstract = {

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.

}, keywords = {N-acylhomoserine lactone acylase, Ntn hydrolase, pathogenesis, Penicillin Vacylase, Quorum quenching}, issn = {0175-7598}, doi = {10.1007/s00253-016-8031-5}, author = {Sunder, Avinash Vellore and Utari, Putri Dwi and Ramasamy, Sureshkumar and van Merkerk, Ronald and Quax, Wim and Pundle, Archana} } @article {46632, title = {Process development for 6-aminopenicillanic acid production using lentikats-encapsulated escherichia coli cells expressing penicillin V acylase}, journal = {ACS Omega}, volume = {5}, year = {2020}, month = {NOV }, pages = {28972-28976}, type = {Article}, abstract = {

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.

}, issn = {2470-1343}, doi = {10.1021/acsomega.0c02813}, author = {Sawant, Amol M. and Sunder, Avinash Vellore and Vamkudoth, Koteswara Rao and Ramasamy, Sureshkumar and Pundle, Archana} } @article {46693, title = {Structural and enzymatic analysis of a dimeric cholylglycine hydrolase like acylase active on N-acyl homoserine lactones}, journal = {Biochimie}, volume = {177}, year = {2020}, month = {OCT}, pages = {108-116}, type = {Article}, abstract = {

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.

}, keywords = {AHL acylase, Cholyolglycine hydrolase, Homodimer, Ntn-fold, Shewanella loihica-PV4}, issn = {0300-9084}, doi = {10.1016/j.biochi.2020.07.017}, author = {Philem, Pushparani D. and Yadav, Yashpal and Sunder, Avinash Vellore and Ghosh, Deepanjan and Prabhune, Asmita and Ramasamy, Sureshkumar} }