02516nas a2200265   4500008004100000022001400041245012500055210006900180260007300249300001400322490000900336520153000345653001901875653002101894653003601915653001301951653002301964653003201987100002202019700001902041700001902060700002102079700002002100856013002120       2013                        eng d  a0304-416500aComplementation of intramolecular interactions for structural-functional stability of plant serine proteinase inhibitors0 aComplementation of intramolecular interactions for structuralfun  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcNOV  a5087-50940 v18303 a<p>Background: Plant protease inhibitors (PIs) constitute a diverse group of proteins capable of inhibiting proteases. Among Pls, serine Pls (SPIs) display stability and conformational restrictions of the reactive site loop by virtue of their compact size, and by the presence of disulfide bonds, hydrogen bonds, and other weak interactions. Scope of review: The significance of various intramolecular interactions contributing to protein folding mechanism and their role in overall stability and activity of SPIs is discussed here. Furthermore, we have reviewed the effect of variation or manipulation of these interactions on the activity/stability of SPIs. Major conclusions: The selective gain or loss of disulfide bond(s) in SPIs can be associated with their functional differentiation, which is likely to be compensated by non-covalent interactions (hydrogen bonding or electrostatic interactions). Thus, these intramolecular interactions are collectively responsible for the functional activity of SPIs, through the maintenance of scaffold framework, conformational rigidity and shape complementarities of reactive site loop. General significance: Structural insight of these interactions will provide an in-depth understanding of kinetic and thermodynamic parameters involved in the folding and stability mechanisms of SPIs. These features can be explored for engineering canonical SPIs for optimizing their overall stability and functionality for various applications. (C) 2013 Elsevier B.V. All rights reserved.</p>10aDisulfide bond10ahydrogen bonding10aIntramolecular weak interaction10aProtease10aReactive site loop10aSerine proteinase inhibitor1 aJoshi, Rakesh, S.1 aMishra, Manasi1 aSuresh, C., G.1 aGupta, Vidya, S.1 aGiri, Ashok, P.  uhttps://library.ncl.res.in/content/complementation-intramolecular-interactions-structural-functional-stability-plant-serine-002335nas a2200253   4500008004100000022001200041245015200053210006900205260000900274300001000283490000700293520141700300653002501717653001301742653002301755653003401778100002601812700002201838700002401860700002401884700002301908700002001931856013001951       2018                        eng d  a965174800aTripeptides derived from reactive centre loop of potato type II protease inhibitors preferentially inhibit midgut proteases of Helicoverpa armigera0 aTripeptides derived from reactive centre loop of potato type II   cAPR   a17-250 v953 a<p>Potato type II protease inhibitors (Pin-II PIs) impede the growth of lepidopteran insects by inhibiting serine protease-like enzymes in the larval gut. The three amino acid reactive centre loop (RCL) of these proteinaceous inhibitors is crucial for protease binding and is conserved across the Pin-II family. However, the molecular mechanism and inhibitory potential of the RCL tripeptides in isolation of the native protein has remained elusive. In this study, six peptides corresponding to the RCLs of the predominant Pin-II PIs were identified, synthesized and evaluated for in vitro and in vivo inhibitory activity against serine proteases of the polyphagous insect, Helicoverpa armigera. RCL peptides with sequences PRN, PRY and TRE were found to be potent inhibitors that adversely affected the growth and development of H. armigera. The binding mechanism and differential affinity of the RCL peptides with serine proteases was delineated by crystal structures of complexes of the RCL peptides with trypsin. Residues P1 and P2 of the inhibitors play a crucial role in the interaction and specificity of these inhibitors. Important features of RCL peptides like higher inhibition of insect proteases, enhanced efficacy at alkaline gut pH, longer retention and high stability in insect gut make them suitable molecules for the development of sustainable pest management strategies for crop protection.</p>10aHelicoverpa armigera10aProtease10aprotease inhibitor10aReactive centre loop peptides1 aSaikhedkar, Nidhi, S.1 aJoshi, Rakesh, S.1 aBhoite, Ashwini, S.1 aMohandasan, Radhika1 aYadav, Amit, Kumar1 aGiri, Ashok, P.  uhttps://library.ncl.res.in/content/tripeptides-derived-reactive-centre-loop-potato-type-ii-protease-inhibitors-preferentially