Oligomerization affects the kinetics and thermodynamics of the interaction of a Bowman-Birk inhibitor with proteases

Abstract

., C. (2017) Oligomerization affects the kinetics and thermodynamics of the interaction of a Bowman-Birk inhibitor with proteases. Archives of Biochemistry and Biophysics, 618, pp. 9-14. (doi:10.1016/j.abb.2017.01.009) This is the author's final accepted version.There may be differences between this version and the published version. You are advised to consult the publisher's version if you wish to cite from it. to the micromolar range, secondary endothermic events become prevalent and affect both the kinetics and thermodynamics of protein associations. Our study reinforces that BBI interactions with serine proteinases should be studied in dilute solutions to abridge often neglected secondary interactions.

First insights into insecticidal activity against Aedes aegypti and partial biochemical characterization of a novel low molecular mass chymotrypsin‐trypsin inhibitor purified from Lonchocarpus sericeus seeds

“…The molecular mass observed for LsCTI was similar to those of other chymotrypsin inhibitors reported, such as the black eyed‐pea chymotrypsin inhibitor (BCTI), from Vigna unguiculata (9.1 kDa) and the wild emmer chymotrypsin inhibitor (WeCI) from Triticum dicoccoides (13 kDa) . It is well known that protease inhibitors generally have more than one isoform .…”

“…The molecular mass observed for LsCTI was similar to those of other chymotrypsin inhibitors reported, such as the black eyed-pea chymotrypsin inhibitor (BCTI), from Vigna unguiculata (9.1 kDa) and the wild emmer chymotrypsin inhibitor (WeCI) from Triticum dicoccoides (13 kDa). 46,47 It is well known that protease inhibitors generally have more than one isoform. 48,49 To verify the presence of isoforms, LsCTI was subjected to a 2D electrophoresis process and in the obtained profile four isoforms were verified with isoelectric points ranging from 4.19 to 4.92 (Figure 3).…”

Interface Interactions of the Bowman–Birk Inhibitor BTCI in a Ternary Complex with Trypsin and Chymotrypsin Evaluated by Semiempirical Quantum Mechanical Calculations

“…This entropy increase occurs due to water molecule exclusion from the protein–protein interface upon protein–protein binding , . However, this analysis should also take into account the concentration of reactive species, since at concentrations below 5 µ m , the inhibitory process of chymotrypsin by BTCI is exothermic . In higher concentrations, endothermic factors are predominant, probably derived from the self‐oligomerization of BTCI.…”

“…The highly conserved aromatic residues – Phe67, Tyr69, and His43 – in a typical T‐shape geometry are showen (Figure A). These residues and the seven disulfide bonds confer a high stability of this inhibitor, being stable and retaining its inhibitory capacity over a wide temperature range – from 25 to 95 °C – and pH – from 3 to 12 , , . As was shown by the crystal structure of the binary and ternary complexes, BTCI inhibits trypsin and chymotrypsin serine proteases simultaneously and independently through two binding sites, with prominent residues of Lys26 and Phe53, respectively, positioned on the opposite sides of BTCI in conserved loops connecting β‐strands, (Figure A).…”

Molecular Cloning and Structure–Function Analysis of a Trypsin Inhibitor from Tartary Buckwheat and Its Application in Combating Phytopathogenic Fungi

“…It has been particularly useful for remotely relevant targets and with a finite template in complicated mixtures. Three rounds of successive PCR amplifications by locus-specific and walker primers and their corresponding nested primers can effectively amplify flanking DNA fragments [14]. Only the correct degenerate primers are designed to ensure that a certain percentage of primers can be paired with the template correctly [15].…”