Structural and biophysical characterization of cajanus cajan protease inhibitor

Abstract

Context:A large number of studies have proven that Protease inhibitors (PIs), specifically serine protease inhibitors, show immense divergence in regulation of proteolysis by targeting their specific proteases and hence, they play a key role in healthcare.Objective:We aimed to access in-vitro anticancer potential of PI from Cajanus cajan (CCPI). Also, crystallization of CCPI was targetted alongwith structure determination and its structure-function relationship.Materials and Methods:CCPI was purified from Cajanus cajan seeds by chromatographic techniques. The purity and molecular mass was determined by SDS-PAGE. Anticancer potential of CCPI was determined by MTT assay in normal HEK and cancerous A549 cells. The crystallization screening of CCPI was performed by commercially available screens. CCPI sequence was subject to BLASTp with homologous PIs. Progressive multiple alignment was performed using clustalw2 and was modelled using ab initio protocol of I-TASSER.Results:The results showed ~14kDa CCPI was purified in homogeneity. Also, CCPI showed low cytotoxic effects of in HEK i.e., 27% as compared with 51% cytotoxicity in A549 cells. CCPI crystallized at 16°C using 15% PEG 6000 in 0.1M potassium phosphate buffer (pH 6.0) in 2-3weeks as rod or needles visualized as clusters under the microscope. The molecular modelling revealed that it contains 3 beta sheets, 3 beta hairpins, 2 β-bulges, 6 strands, 3 helices, 1helix-helix interaction, 41 β-turns and 27 γ-turns.Discussion and Conclusion:The results indicate that CCPI may help to treat cancer in vivo aswell. Also, this is the first report on preliminary crystallization and structural studies of CCPI.

Conservation and sustainable use of the medicinal Leguminosae plants from Angola

“…The methanol extract of the bark of Guibourtia tessmannii (Harms) J.Leonard (from Cameroon) has shown antiproliferative activity against cervical cancer cells (Kuete et al, 2013), while serine protease inhibitors from Cajanus cajan (L.) Millsp. seeds (also known as the pigeon pea) demonstrated anticancer potential (Shamsi et al., 2017).…”

A Wild Cajanus scarabaeoides (L.), Thouars, IBS 3471, for Improved Insect-Resistance in Cultivated Pigeonpea

“…Several in vitro and in vivo studies showed that PPIs are toxic to larval gut proteases, causing digestion defects and disruption of amino acid absorption. Besides, PPIs result in retarded growth and development of the larvae, consequently affecting the fecundity and productivity of the moth [13]. Similarly, C. scarabaeoides accession IBS 3471 contained the largest quantities of cysteine proteinase inhibitors and lectin-domain containing receptor kinases ( Figure 5), resulting in the most significant inhibition to H. armigera larval growth (Figures 1, 3 and 4; Supplementary Table S3).…”