02045nas a2200265   4500008004100000022001400041245009700055210006900152260007500221300001200296490000700308520112300315653001601438653001701454653001801471653001301489653002101502653002301523653002101546100001901567700001901586700002601605700002501631856012301656       2008                        eng d  a1053-050900aSteady state and time-resolved fluorescence studies of a hemagglutinin from Moringa oleifera0 aSteady state and timeresolved fluorescence studies of a hemagglu  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGER/PLENUM PUBLISHERScMAR  a479-4850 v183 a<p>The saccharide binding and conformational characterization of a hemagglutinin, a low molecular weight protein from the seeds of Moringa oleifera was studied using steady state and time resolved fluorescence. The lectin binds sugars LacNAc (K-a = 1380 M-1) and fructose (K-a = 975 M-1), as determined by the fluorescence spectroscopy. It has a single tryptophan per monomer which is exposed on the surface and is in a strong electropositive environment as revealed by quenching with iodide. Quenching of the fluorescence by acrylamide involved both static (K-s = 0.216 M-1) and collisional (K-sv= 8.19 M-1) components. The native protein showed two different lifetimes, tau(1) (1.6 ns) and tau(2) (4.36 ns) which decrease and get converted into a single one, (2.21 ns) after quenching with 0.15 M acrylamide. The bimolecular quenching constant, k(q) was 7.55 x 10(11) M-1 s(-1). ANS binding studies showed that the native protein has exposed hydrophobic patches which get further exposed at extreme acidic or alkaline pH. However, they get buried in the interior of the protein in presence of 1 M GdnHCl or urea.</p>10aANS binding10afluorescence10aHemagglutinin10alifetime10aMoringa oleifera10asaccharide binding10aSolute quenching1 aKatre, Uma, V.1 aSuresh, C., G.1 aKhan, Mohammad, Islam1 aGaikwad, Sushama, M.  uhttp://library.ncl.res.in/content/steady-state-and-time-resolved-fluorescence-studies-hemagglutinin-moringa-oleifera-002219nas a2200241   4500008004100000022001400041245012000055210006900175260000900244300001200253490000800265520138800273653001701661653001901678653001101697653001901708653002301727653002401750100002801774700002101802700002501823856012901848       2019                        eng d  a0003-986100aInvestigation of structural and saccharide binding transitions of Bauhinia purpurea and Wisteria floribunda lectins0 aInvestigation of structural and saccharide binding transitions o  cFEB   a134-1420 v6623 a<p>Two novel medicinally important legume lectins from Bauhinia purpurea (BPL) and Wisteria floribunda (WFL) possessing extended sugar binding site were investigated for functional and conformational transitions using biochemical and biophysical techniques as well as bioinformatical tools. Homology model of BPL was constructed using the Schrodinger suite and docked with N-acetyl galactosamine and T-antigen disaccharide (Gal beta 1-3GalNAc alpha O-Me). The longer loop D in the structure of WFL compared to that in BPL was found to be responsible for its specificity to LacdiNac (beta-D-GalNAc-[1 -&gt; 4]-DGlcNAc) over Gal beta 1-3GalNAc. BPL remained functionally stable up to 40 degrees C whereas WFL remained stable upto 70 degrees C indicating the strength of the sugar binding site geometry. Both the lectins showed intense but non-specific secondary structure in the range of 65-90 degrees C. WFL showed rapid aggregation above 80 degrees C as indicated by light scattering intensity. The lectins showed simultaneous dissociation and multistate unfolding in the vicinity of GdnHCl. At pH 1.0, both the lectins exhibited molten globule like structures, which were characterized further and were found to respond in a different way towards denaturants. The results have provided valuable insights into the molecular basis of the activity and stability of the two lectins.</p>10aConformation10aHomology model10aLectin10aMolten globule10asaccharide binding10aThermal aggregation1 aAgrawal, Sanskruthi, B.1 aGhosh, Deepanjan1 aGaikwad, Sushama, M.  uhttp://library.ncl.res.in/content/investigation-structural-and-saccharide-binding-transitions-bauhinia-purpurea-and-wisteria