Purification, characterization and molecular cloning of chymotrypsin inhibitor peptides from the venom of Burmese Daboia russelii siamensis.

One novel Kunitz BPTI-like peptide designated as BBPTI-1, with chymotrypsin inhibitory activity was identified from the venom of Burmese Daboia russelii siamensis. It was purified by three steps of chromatography including gel filtration, cation exchange and reversed phase. A partial N-terminal sequence of BBPTI-1, HDRPKFCYLPADPGECLAHMRSF was obtained by automated Edman degradation and a Ki value of 4.

Trypsin and chymotrypsin inhibitor peptides from the venom of Chinese Daboia russellii siamensis.

Two trypsin inhibitors and one chymotrypsin inhibitor from Chinese Daboia russellii siamensis venom, denoted as CBPTI-1, CBPTI-2 and CBPTI-3 were purified, characterized and cloned from lyophilized venom-derived cDNA libraries. The N-terminus of CBPTI-1 was modified and not amenable to Edman degradation sequencing, however an internal partial sequence was found to be SGRCRGHLRRIYYNPDSNKCE. The N-termini of CBPTI-2 and CBPTI-3 were unmodified and their partial sequences were established as HDRPTFCNLAPESGRCRAH and HDRPKFCYLPADPGECMAYIRSFYYDS respectively.

[Isolation and purification of ribosome-inactivating proteins from bitter melon seeds by ion exchange chromatographic columns in series].

An anion exchange chromatographic column (DEAE-650C) and a cation exchange chromatographic column (CM-650C) were connected in series on a perfusion chromatography workstation. The crude extract of bitter melon seeds flowed through the two columns and the unadsorbed fraction on the DEAE-650C column was then directly readsorbed on the CM-650C column. Two protein components with antifungal activity were eluted from the cation exchange chromatographic column by linear salt gradient.

[Separation and purification of cellulase using affinity membrane].

The importance of cellulase as a means for the efficient utilization of abundant cellulose resources in the world has been well recognized. Many researchers devote themselves to studying the mechanism of the action of cellulase to cellulose so that such expensive enzyme can be used much more widely. The first step is to obtain cellulase of high purity.