02327nas a2200253   4500008004100000022001400041245013200055210006900187260009900256300001200355490000700367520135500374653002501729653002601754653002501780653001701805653002701822653002601849100001601875700002101891700001901912700002001931856012201951       2008                        eng d  a1359-511300aCharacterization of smallest active monomeric penicillin V acylase from new source: a yeast, rhodotorula aurantiaca (NCIM 3425)0 aCharacterization of smallest active monomeric penicillin V acyla  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcSEP  a961-9670 v433 a<p>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.</p>10aIntracellular enzyme10aN-terminal sequencing10aPenicillin V acylase10aPurification10aRhodotorula aurantiaca10aSubstrate specificity1 aKumar, Atul1 aPrabhune, Asmita1 aSuresh, C., G.1 aPundle, Archana  uhttps://library.ncl.res.in/content/characterization-smallest-active-monomeric-penicillin-v-acylase-new-source-yeast-002078nas a2200253   4500008004100000022001400041245019000055210006900245260007900314300001200393490000800405520106000413653002801473653002501501653002401526653002101550653002701571100001601598700001801614700001901632700002101651700002001672856013201692       2009                        eng d  a0273-228900aEffect 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)0 aEffect of cultural conditions and media constituents on producti  a999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USAbHUMANA PRESS INCcJUN  a463-4720 v1573 a<p>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.</p>10aAtomic force microscopy10aIntracellular enzyme10aPenicillin Vacylase10aPermeabilization10aRhodotorula aurantiaca1 aKumar, Atul1 aSingh, Sanjay1 aPoddar, Pankaj1 aPrabhune, Asmita1 aPundle, Archana  uhttps://library.ncl.res.in/content/effect-cultural-conditions-and-media-constituents-production-penicillin-v-acylase-and-ctab-002493nas a2200229   4500008004100000022001400041245010300055210006900158260006900227300001200296490000700308520163100315653002501946653002501971653002501996653002702021100001602048700002302064700002502087700002002112856013102132       2009                        eng d  a1011-134400aRhodotorula aurantiaca penicillin V acylase: active site characterization and fluorometric studies0 aRhodotorula aurantiaca penicillin V acylase active site characte  aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcNOV  a109-1160 v973 a<p>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.</p>10aactive site residues10aFluorometric studies10aPenicillin V acylase10aRhodotorula aurantiaca1 aKumar, Atul1 aGowda, Nagaraj, M.1 aGaikwad, Sushama, M.1 aPundle, Archana  uhttps://library.ncl.res.in/content/rhodotorula-aurantiaca-penicillin-v-acylase-active-site-characterization-and-fluorometric-0