<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kumar, Atul</style></author><author><style face="normal" font="default" size="100%">Prabhune, Asmita</style></author><author><style face="normal" font="default" size="100%">Suresh, C. G.</style></author><author><style face="normal" font="default" size="100%">Pundle, Archana</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Characterization of smallest active monomeric penicillin V acylase from new source: a yeast, rhodotorula aurantiaca (NCIM 3425)</style></title><secondary-title><style face="normal" font="default" size="100%">Process Biochemistry</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Intracellular enzyme</style></keyword><keyword><style  face="normal" font="default" size="100%">N-terminal sequencing</style></keyword><keyword><style  face="normal" font="default" size="100%">Penicillin V acylase</style></keyword><keyword><style  face="normal" font="default" size="100%">Purification</style></keyword><keyword><style  face="normal" font="default" size="100%">Rhodotorula aurantiaca</style></keyword><keyword><style  face="normal" font="default" size="100%">Substrate specificity</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">SEP</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">9</style></number><publisher><style face="normal" font="default" size="100%">ELSEVIER SCI LTD</style></publisher><pub-location><style face="normal" font="default" size="100%">THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND</style></pub-location><volume><style face="normal" font="default" size="100%">43</style></volume><pages><style face="normal" font="default" size="100%">961-967</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;An intracellular monomeric penicillin V acylase (PVA) of 36,000 Da exhibiting pI of 4.19, purified from newly identified yeast source, Rhodotorula aurantiaca (NCIM 3425). The enzyme was purified by hydrophobic interaction chromatography. The enzyme showed optimal activity at 45 degrees C and retained 80% activity after incubation at 45 degrees C and pH 5.5 for I h. The enzyme showed maximum activity at pH 5.5 and was very stable between pH 5.5-6.5 with optimum stability at pH 6.0. It exhibited 50% of its original activity after 30 min incubation at 60 degrees C. Enzyme hydrolyzed substrates with benzyl side chain but preferred penicillin V as primary substrate. N-terminally located serine supports the fact that it belongs to Ntn (N-terminal nucleophile)-hydrolase superfamily. The initial ten amino acid residues of R. aurantiaca PVA were identical to the initial sequence of NADH dehydrogenase (EC 1.6.99.3): however the enzyme lacks dehydrogenase activity. EGTA, EDTA, hexane and ethyl acetate stabilized the activity where as small chain alcohols inhibited it. 1,4-Dioxane, THF (tetrahydrofurane), phenol and benzyl alcohol severely inhibited enzyme activity while BME and DTT increased it. Tween 80 and Tween 20 highly enhanced the activity where as SIDS and Triton X-100 inhibited it. (C) 2008 Elsevier Ltd. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">2.529</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kumar, Atul</style></author><author><style face="normal" font="default" size="100%">Singh, Sanjay</style></author><author><style face="normal" font="default" size="100%">Poddar, Pankaj</style></author><author><style face="normal" font="default" size="100%">Prabhune, Asmita</style></author><author><style face="normal" font="default" size="100%">Pundle, Archana</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of cultural conditions and media constituents on production of penicillin V acylase and CTAB treatment to enhance whole-cell enzyme activity of rhodotorula aurantiaca (NCIM 3425)</style></title><secondary-title><style face="normal" font="default" size="100%">Applied Biochemistry and Biotechnology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Atomic force microscopy</style></keyword><keyword><style  face="normal" font="default" size="100%">Intracellular enzyme</style></keyword><keyword><style  face="normal" font="default" size="100%">Penicillin Vacylase</style></keyword><keyword><style  face="normal" font="default" size="100%">Permeabilization</style></keyword><keyword><style  face="normal" font="default" size="100%">Rhodotorula aurantiaca</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">JUN</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">3</style></number><publisher><style face="normal" font="default" size="100%">HUMANA PRESS INC</style></publisher><pub-location><style face="normal" font="default" size="100%">999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USA</style></pub-location><volume><style face="normal" font="default" size="100%">157</style></volume><pages><style face="normal" font="default" size="100%">463-472</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Penicillin V acylase (PVA) is a pharmaceutically important enzyme as it plays a vital role in the manufacture of semi-synthetic beta-lactam antibiotics. Rhodotorula aurantiaca (NCIM 3425) produced high levels of intracellular penicillin V acylase after 18 h at pH 8.0 and temperature 27 degrees C. Fructose was the best carbon source for PVA production, whereas tryptone was the best nitrogen source to produce the enzyme up to 170 and 1,088 IU/l of culture, respectively. Additionally, the cell-bound PVA activity was enhanced on treatment with cationic detergent. Whole-cell activity was found to be doubled (204%) on treatment of 0.01 g dry weight of cells with 50 mu g/ml solution of N-cetyl-N,N,N-trimethylammoniumbromide at pH 8.0 for 1 h at room temperature. Atomic force microscopy images of permeabilized cells show perturbation in the cell wall and offer first-ever visual illustration of surface structure modifications that occur during permeabilization of R. aurantiaca cells leading to enhancement in activity of intracellular enzyme.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">1.879</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kumar, Atul</style></author><author><style face="normal" font="default" size="100%">Gowda, Nagaraj M.</style></author><author><style face="normal" font="default" size="100%">Gaikwad, Sushama M.</style></author><author><style face="normal" font="default" size="100%">Pundle, Archana</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Rhodotorula aurantiaca penicillin V acylase: active site characterization and fluorometric studies</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Photochemistry and Photobiology B-Biology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">active site residues</style></keyword><keyword><style  face="normal" font="default" size="100%">Fluorometric studies</style></keyword><keyword><style  face="normal" font="default" size="100%">Penicillin V acylase</style></keyword><keyword><style  face="normal" font="default" size="100%">Rhodotorula aurantiaca</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">NOV</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">2</style></number><publisher><style face="normal" font="default" size="100%">ELSEVIER SCIENCE SA</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 564, 1001 LAUSANNE, SWITZERLAND</style></pub-location><volume><style face="normal" font="default" size="100%">97</style></volume><pages><style face="normal" font="default" size="100%">109-116</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Penicillin V acylase (PVA), a member of newly evolved Ntn-hydrolase superfamily, is a pharmaceutically important enzyme to produce 6-aminopenicillanic acid. Active site characterization of recently purified monomeric PVA from Rhodotorula aurantiaca (Ra-PVA), the yeast source, showed the involvement of serine and tryptophan in the enzyme activity. Modification of the protein with serine and tryptophan specific reagents such as PMSF and NBS showed partial loss of PVA activity and substrate protection. Ra-PVA was found to be a multi-tryptophan protein exhibiting one tryptophan, in native and, four in its denatured condition. Various solute quenchers and substrate were used to probe the microenvironment of the putative reactive tryptophan through fluorescence quenching. The results obtained indicate that the tryptophan residues of Ra-PVA were largely buried in hydrophobic core of the protein matrix. Quenching of the fluorescence by acrylamide was collisional. Acrylamide was the most effective quencher amongst all the used quenchers, which quenched 71.6% of the total intrinsic fluorescence of the protein, at a very less final concentration of 0.1 M. Surface tryptophan residues were found to have predominantly more electropositively charged amino acids around them, however differentially accessible for ionic quenchers. Denaturation led to shift lambda(max) from 336, in native state, to 357 nm and more exposed to the solvent, consequently increase in fluorescence quenching with all quenchers. This is an attempt towards the conformational studies of Ra-PVA. (C) 2009 Elsevier B.V. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">2.116</style></custom4></record></records></xml>