title: Isolation and purification of trypsin inhibitors from the seeds of Abelmoschus moschatus L.
abstract: Four trypsin inhibitors, AMTI-I, AMTI-II, AMTI-III, and AMTI-IV, have been isolated and purified to homogeneity from the seeds of Abelmoschus moschatus following ammonium sulphate fractionation, DEAE-cellulose ion exchange chromatography and gel permeation on Sephadex G-100, and their molecular weights were determined to be 22.4, 21.2, 20.8 and 20.2 kDa respectively by SDS-PAGE. While all the four inhibitors were very active against bovine trypsin, two of them (AMTI-III and AMTI-IV) showed moderate activity towards bovine chymotrypsin. AMTI-I and AMTI-II were found to be glycoproteins with neutral sugar content of 2.8 and 4 %, respectively, and all the four inhibitors were devoid of free sulphhydryl groups. The inhibitors were quite stable up to 80 °C for 10 min and were not affected at alkaline as well as acidic conditions tested. Treating them with 8 M urea and 1 % SDS for 24 h at room temperature did not result in any loss of their antitryptic activities. However, they lost considerable antitryptic activity when treated with 6 M guanidine hydrochloride. Activities of the inhibitors were unaffected even after their reduction with DTT suggesting that disulphide bonds are not needed for their inhibitory activities.
authors.affiliation: Department of Biochemistry, Andhra University, Visakhapatnam, 530 003, Andhra Pradesh, India, munikumarbiochem@gmail.com.
authors.forename: Muni Kumar
authors.initials: MK
authors.lastname: Dokka
authors.forename: Lavanya
authors.initials: L
authors.lastname: Seva
authors.forename: Siva Prasad
authors.initials: SP
authors.lastname: Davuluri
mesh_terms: D028483:Abelmoschus / Q000737:chemistry*; D000818:Animals; D002417:Cattle; D006863:Hydrogen-Ion Concentration; D012639:Seeds / Q000737:chemistry; D014357:Trypsin / Q000737:chemistry / Q000378:metabolism; D014361:Trypsin Inhibitors / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D014361:Trypsin Inhibitors; D014357:Trypsin