<?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%">Shashidhara, K. S.</style></author><author><style face="normal" font="default" size="100%">Gaikwad, Sushama M.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Fluorescence quenching and time-resolved fluorescence studies of alpha-Mannosidase from Aspergillus fischeri (NCIM 508)</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Fluorescence</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">alpha-Mannosidase</style></keyword><keyword><style  face="normal" font="default" size="100%">Denaturation</style></keyword><keyword><style  face="normal" font="default" size="100%">fluorescence</style></keyword><keyword><style  face="normal" font="default" size="100%">lifetime</style></keyword><keyword><style  face="normal" font="default" size="100%">Solute quenching</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2007</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%">6</style></number><publisher><style face="normal" font="default" size="100%">SPRINGER/PLENUM PUBLISHERS</style></publisher><pub-location><style face="normal" font="default" size="100%">233 SPRING ST, NEW YORK, NY 10013 USA</style></pub-location><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">599-605</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Apart from the vital role in glycoprotein biosynthesis and degradation, alpha-mannosidase is currently an important therapeutic target for the development of anticancer agents. Fluorescence quenching and time-resolved fluorescence of alpha-mannosidase, a multitryptophan protein from Aspergillus fischeri were carried out to investigate the tryptophan environment. The tryptophans were found to be differentially exposed to the solvent and were not fully accessible to the neutral quencher indicating heterogeneity in the environment. Quenching of the fluorescence by acrylamide was collisional. Surface tryptophans were found to have predominantly positively charged amino acids around them and differentially accessible to the ionic quenchers. Denaturation led to more exposure of tryptophans to the solvent and consequently in the significant increase in quenching with all the quenchers. The native enzyme showed two different lifetimes, tau (1) (1.51 ns) and tau (2) (5.99 ns). The average lifetime of the native protein (tau) (3.187 ns) was not affected much after denaturation (tau) (3.219 ns), while average lifetime of the quenched protein samples was drastically reduced (1.995 ns for acrylamide and 1.537 ns for iodide). This is an attempt towards the conformational studies of alpha-mannosidase.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">6</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%">1.601</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%">Mohapatra, Debendra K.</style></author><author><style face="normal" font="default" size="100%">Bhattasali, Debabrata</style></author><author><style face="normal" font="default" size="100%">Gujar, Mukund K.</style></author><author><style face="normal" font="default" size="100%">Khan, Mohammad Islam</style></author><author><style face="normal" font="default" size="100%">Shashidhara, K. S.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">First asymmetric total synthesis of penarolide sulfate A(1)</style></title><secondary-title><style face="normal" font="default" size="100%">European Journal of Organic Chemistry</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Asymmetric synthesis</style></keyword><keyword><style  face="normal" font="default" size="100%">C-C coupling</style></keyword><keyword><style  face="normal" font="default" size="100%">Dihydroxylation</style></keyword><keyword><style  face="normal" font="default" size="100%">epoxidation</style></keyword><keyword><style  face="normal" font="default" size="100%">Macrocycles</style></keyword><keyword><style  face="normal" font="default" size="100%">Regioselectivity</style></keyword><keyword><style  face="normal" font="default" size="100%">Total synthesis</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%">DEC</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">36</style></number><publisher><style face="normal" font="default" size="100%">WILEY-BLACKWELL</style></publisher><pub-location><style face="normal" font="default" size="100%">COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA</style></pub-location><pages><style face="normal" font="default" size="100%">6213-6224</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Penarolide sulfate A(1), with three contiguous stereogenic centers on a macrocyclic skeleton, affords promise as an alpha-glucosidase inhibitor. Herein, we describe the first asymmetric total synthesis of this natural product. A stereoselective strategy for rapid assembly of the complete framework of the 30-membered macrocyclic core is delineated herein. Sequential amidation and intramolecular Sonogashira cross-coupling reactions were pivotal to the success of our efforts. ((C) Wiley-VCH Verlag GmbH &amp;amp; Co. KGaA, 69451 Weinheim, Germany, 2008)&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">36</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%">3.068</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%">Pandey, Ganesh</style></author><author><style face="normal" font="default" size="100%">Bharadwaj, Kishor Chandra</style></author><author><style face="normal" font="default" size="100%">Khan, Mohammad Islam</style></author><author><style face="normal" font="default" size="100%">Shashidhara, K. S.</style></author><author><style face="normal" font="default" size="100%">Puranik, Vedavati G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Synthesis of polyhydroxy piperidines and their analogues: a novel approach towards selective inhibitors of alpha-glucosidase</style></title><secondary-title><style face="normal" font="default" size="100%">Organic &amp; Biomolecular Chemistry</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">JAN</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">14</style></number><publisher><style face="normal" font="default" size="100%">ROYAL SOC CHEMISTRY</style></publisher><pub-location><style face="normal" font="default" size="100%">THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND</style></pub-location><volume><style face="normal" font="default" size="100%">6</style></volume><pages><style face="normal" font="default" size="100%">2587-2595</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Various polyhydroxy piperidine azasugars have been synthesized from precursors 18a and 18b, obtained in both enantiomeric forms from D-ribose. Out of these polyhydroxy piperidine azasugars, 22, 39 and 20 were found to be potent as well as selective inhibitors of a-glucosidase with K(i) values ranging as low as 1.07 mu M, 16.4 mu M, and 88.2 mu M, respectively. Replacement of the hydroxy methylene moiety of 19 (K(i) 33% at 1 mM) by an amino methylene moiety (32, K(i) 36.8 mu M) showed a remarkable increase in the activity (almost 30 times). Furthermore, increasing the lipophilicity of 33 by N-alkylation with a dodecyl group (36) showed a three-fold enhancement in the activity (K(i) 217 mu M to K(i) 72.3 mu M).&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">14</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%">3.559</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%">Shashidhara, K. S.</style></author><author><style face="normal" font="default" size="100%">Gaikwad, Sushama M.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Class II alpha-mannosidase from aspergillus fischeri: energetics of catalysis and inhibition</style></title><secondary-title><style face="normal" font="default" size="100%">International Journal of Biological Macromolecules</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">alpha-Mannosidase</style></keyword><keyword><style  face="normal" font="default" size="100%">Energy of activation</style></keyword><keyword><style  face="normal" font="default" size="100%">kinetics</style></keyword><keyword><style  face="normal" font="default" size="100%">Swainsonine</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%">JAN</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">1</style></number><publisher><style face="normal" font="default" size="100%">ELSEVIER SCIENCE BV</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS</style></pub-location><volume><style face="normal" font="default" size="100%">44</style></volume><pages><style face="normal" font="default" size="100%">112-115</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Energetics of the catalysis of Class II alpha-mannosidase (E.C.3.2.1.24) from Aspergillus fischeri was studied. The enzyme showed K(cat)/K(m) for Man (alpha 1-3) Man, Man (alpha 1-2) Man and Man (alpha 1-6) Man as 7488, 5376 and 3690 M(-1) min(-1), respectively. The activation energy, Ea was 15.14, 47.43 and 71.21 kJ/mol for a1-3, alpha 1-2 and alpha 1-6 linked mannobioses, respectively, reflecting the energy barrier in the hydrolysis of latter two substrates. The enzyme showed K(cat)/K(m) as 3.56 x 10(5) and 4.61 x 10(5) M(-1) min(-1) and E(a) as 38.7 and 8.92 kJ/mol, towards pNP alpha Man and 4-MeUmb alpha Man, respectively. Binding of Swainsonine to the enzyme is stronger than that of 1-deoxymannojirimycin. (C) 2008 Elsevier B.V. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">2.502</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%">Shashidhara, K. S.</style></author><author><style face="normal" font="default" size="100%">Gaikwad, S. M.</style></author><author><style face="normal" font="default" size="100%">Khan, Mohammad Islam</style></author><author><style face="normal" font="default" size="100%">Bharadwaj, Kishor Chandra</style></author><author><style face="normal" font="default" size="100%">Pandey, G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Interaction of alpha-mannosidase from aspergillus fischeri with glycosidase inhibitors, metal ions and group specific reagents</style></title><secondary-title><style face="normal" font="default" size="100%">Research Journal of Biotechnology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">active-site</style></keyword><keyword><style  face="normal" font="default" size="100%">alpha-Mannosidase</style></keyword><keyword><style  face="normal" font="default" size="100%">Chemical modification</style></keyword><keyword><style  face="normal" font="default" size="100%">Glycosidase inhibitors</style></keyword><keyword><style  face="normal" font="default" size="100%">metal ions</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%">4</style></number><publisher><style face="normal" font="default" size="100%">RESEARCH JOURNAL BIOTECHNOLOGY</style></publisher><pub-location><style face="normal" font="default" size="100%">SECTOR A-80, SCHEME NO 54, VIJAY NAGAR, A B ROAD, INDORE, 452 010 MP, INDIA</style></pub-location><volume><style face="normal" font="default" size="100%">4</style></volume><pages><style face="normal" font="default" size="100%">39-48</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;As an initial step towards using alpha-mannosidase as a target against anticancer drugs, inhibition studies of a model enzyme, class II alpha-mannosidase from Aspergillus fischeri in presence of polyhydroxy piperidine derived glycosidase inhibitors, metal ions and amino acid specific reagents were carried out to reveal the sensitivity of the enzyme. Three of the derivatives (Compound 20, 32 and 39)(11) showed competitive inhibition (K(i) =45, 48 and 235 mu M) and the binding of the inhibitors to the enzyme was entropically driven. Among the metal ions checked, Cu(++) (K(i) = 21nm) and Se(++) ions (K(i) = 32 mu M) showed noncompetitive and Co(++) (K(i) = 1.195 mM) showed competitive inhibition of the enzyme activity with insignificant change in the secondary structure of the protein. The above studies exhibit the Potential of the enzyme in studying anticancer drugs. Treatment of the enzyme with group specific reagents showed the presence of carboxylate, Arg and Cys at the active site. Substrate protection studies and kinetics of the modified enzyme confirmed the above results. Trp and His at the active site were observed to be in proximity.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom3><style face="normal" font="default" size="100%">Indian</style></custom3><custom4><style face="normal" font="default" size="100%">0.284</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%">Pandey, Ganesh</style></author><author><style face="normal" font="default" size="100%">Grahacharya, Debasish</style></author><author><style face="normal" font="default" size="100%">Shashidhara, K. S.</style></author><author><style face="normal" font="default" size="100%">Khan, Mohammad Islam</style></author><author><style face="normal" font="default" size="100%">Puranik, Vedavati G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Synthesis of polyfunctional quinolizidine alkaloids: development towards selective glycosidase inhibitors</style></title><secondary-title><style face="normal" font="default" size="100%">Organic &amp; Biomolecular Chemistry</style></secondary-title></titles><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%">16</style></number><publisher><style face="normal" font="default" size="100%">ROYAL SOC CHEMISTRY</style></publisher><pub-location><style face="normal" font="default" size="100%">THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND</style></pub-location><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">3300-3307</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;A highly divergent route to a variety of quinolizidine alkaloids is described. The enantiomeric precursors 22a and 22b utilized for the synthesis of these alkaloids were constructed stereospecifically from the PET cyclization of the corresponding acetylene tethered alpha-trimethylsilyl amine moieties 21a and 21b, respectively, both of which were synthesised from D-ribose. The polyhydroxy quinolizidine alkaloid 7 was found to be a selective inhibitor of alpha-galactosidase with Ki 83.9 mu M. The amine analogs 18, 12 and 10 are found to be selective and potent inhibitors of alpha-glucosidase with Ki 28, 120 and 140 mu M, respectively.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">16</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">3.451</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%">Shashidhara, K. S.</style></author><author><style face="normal" font="default" size="100%">Gaikwad, Sushama M.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Conformational and functional transitions in class II alpha-mannosidase from aspergillus fischeri</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Fluorescence</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Aggregation</style></keyword><keyword><style  face="normal" font="default" size="100%">alpha-Mannosidase</style></keyword><keyword><style  face="normal" font="default" size="100%">ANS binding</style></keyword><keyword><style  face="normal" font="default" size="100%">Circular dichroism</style></keyword><keyword><style  face="normal" font="default" size="100%">fluorescence</style></keyword><keyword><style  face="normal" font="default" size="100%">GdnHCl</style></keyword><keyword><style  face="normal" font="default" size="100%">Hydrobicity</style></keyword><keyword><style  face="normal" font="default" size="100%">Thermal denaturation</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">JUL</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">4</style></number><publisher><style face="normal" font="default" size="100%">SPRINGER/PLENUM PUBLISHERS</style></publisher><pub-location><style face="normal" font="default" size="100%">233 SPRING ST, NEW YORK, NY 10013 USA</style></pub-location><volume><style face="normal" font="default" size="100%">20</style></volume><pages><style face="normal" font="default" size="100%">827-836</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;The conformational transitions in an oligomeric and high molecular weight class II alpha-mannosidase from Aspergillus fischeri were examined using fluorescence and CD spectroscopy under chemical, thermal and acid denaturing conditions. The enzyme lost the activity first and then the overall folded conformation and secondary structure. The midpoint values of GdnHCl mediated changes measured by inactivation; fluorescence and negative ellipticity were 0.48 M, 1.5 M and 1.9 M, respectively. The protein almost completely unfolded in 4.0 M GdnHCl but not at 90 A degrees C. The inactivation and unfolding were irreversible. At pH 2.0, the protein exhibited molten-globule like intermediate with rearranged secondary and tertiary structures and exposed hydrophobic amino acids on the surface. This species showed increased accessibility of Trp to the quenchers and got denatured with GdnHCl in a different manner. The insoluble aggregates of a thermally denatured protein could be detected only in the presence of 0.25-0.75 M GdnHCl.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">1.966</style></custom4></record></records></xml>