02993nas a2200289   4500008004100000022001400041245017700055210006900232260008600301300001000387490000700397520189300404653002002297653002502317653001402342653002502356100002202381700001902403700002802422700001902450700002402469700001902493700002002512700002102532700002002553856013002573       2014                        eng d  a0739-110200aRemarkable efficiency of a pin-II proteinase inhibitor sans two conserved disulfide bonds is due to enhanced flexibility and hydrogen bond density in the reactive site loop0 aRemarkable efficiency of a pinII proteinase inhibitor sans two c  a325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USAbTAYLOR & FRANCIS INCcJAN  a13-260 v323 a<p>Capsicum annuum (L.) expresses diverse potato type II family proteinase inhibitors comprising of inhibitory repeat domain (IRD) as basic functional unit. Most IRDs contain eight conserved cysteines forming four disulfide bonds, which are indispensible for their stability and activity. We investigated the functional significance of evolutionary variations in IRDs and their role in mediating interaction between the inhibitor and cognate proteinase. Among the 18 IRDs encoded by C. annuum, IRD-7, -9, and -12 were selected for further characterization on the basis of variation in their reactive site loop, number of conserved cysteine residues, and higher theoretical G(bind) for interaction with Helicoverpa armigera trypsin. Moreover, inhibition kinetics showed that IRD-9, despite loss of some of the disulfide bonds, was a more potent proteinase inhibitor among the three selected IRDs. Molecular dynamic simulations revealed that serine residues in the place of cysteines at seventh and eighth positions of IRD-9 resulted in an increase in the density of intramolecular hydrogen bonds and reactive site loop flexibility. Results of the serine residues chemical modification also supported this observation and provided a possible explanation for the remarkable inhibitory potential of IRD-9. Furthermore, this natural variant among IRDs showed special attributes like stability to proteolysis and synergistic inhibitory effect on other IRDs. It is likely that IRDs have coevolved selective specialization of their structure and function as a response towards specific insect proteases they encountered. Understanding the molecular mechanism of pest protease-plant proteinaceous inhibitor interaction will help in developing effective pest control strategies.An animated interactive 3D complement (I3DC) is available in Proteopedia at http://proteopedia.org/w/Journal:JBSD:39</p>10aCapsicum annuum10aHelicoverpa armigera10aProteases10aProteinase inhibitor1 aJoshi, Rakesh, S.1 aMishra, Manasi1 aTamhane, Vaijayanti, A.1 aGhosh, Anirban1 aSonavane, Uddhavesh1 aSuresh, C., G.1 aJoshi, Rajendra1 aGupta, Vidya, S.1 aGiri, Ashok, P.  uhttps://library.ncl.res.in/content/remarkable-efficiency-pin-ii-proteinase-inhibitor-sans-two-conserved-disulfide-bonds-due-002333nas a2200289   4500008004100000022001400041245007800055210006900133260000800202300001100210490000800221520142300229653001401652653002401666653002401690653002201714653003301736653002201769100001801791700001601809700002401825700002201849700002001871700002501891700002001916856010701936       2024                        eng d  a0141-813000aMulti-dimensional impact of captopril modification on human serum albumin0 aMultidimensional impact of captopril modification on human serum  cAUG  a1332890 v2743 a<p>
	Captopril is a thiol drug, widely used for the management of hypertension and cardiovascular diseases. Reactive thiols are found to covalently modify the cysteines of plasma proteins and affect their structure and function. Human serum albumin (HSA) is prone to undergo modification by various low molecular weight compounds, including drugs. Cysteine34 (Cys34) in HSA has a free thiol group with antioxidant properties, considered to be the most redox-sensitive amino acid in plasma. Through mass-spectrometric analysis, we demonstrate for the first time that captopril forms a disulfide adduct at Cys34 residue and increases the protease susceptibility of HSA to trypsin. As evidenced by our biophysical and electron microscopy studies, HSA undergoes structural alteration, aggregation and morphological changes when treated with different captopril concentrations. Molecular dynamics studies further revealed the regions of secondary structural changes in HSA due to disulfide adduct formation by captopril at Cys34. It also elucidated the residues involved in the noncovalent interactions with captopril. It is envisaged that structural change in HSA may influence the efficacy of drug delivery as well as its own biological function. These findings may thus provide significant insights into the field of pharmacology intriguing further investigation into the effects of long-term captopril treatment.</p>
10aCaptopril10aElectron microscopy10aHuman serum albumin10aMass spectrometry10aMolecular dynamic simulation10aSpectrophotometry1 aGhosh, Amrita1 aJani, Vinod1 aSonavane, Uddhavesh1 aNaphade, Anvi, N.1 aJoshi, Rajendra1 aKulkarni, Mahesh, J.1 aGiri, Ashok, P.  uhttps://library.ncl.res.in/content/multi-dimensional-impact-captopril-modification-human-serum-albumin