Deakin University
Browse

File(s) under permanent embargo

Purification and functional characterization of recombinant balsamin, a ribosome-inactivating protein from Momordica balsamina

journal contribution
posted on 2018-07-15, 00:00 authored by Parminder K Ajji, Shailendra P Sonkar, Ken WalderKen Walder, Munish PuriMunish Puri
Balsamin, a type I ribosome-inactivating protein (RIP), has been shown to inhibit HIV-1 replication at the translation step. Our recent studies have shown that balsamin also possess anti-tumor, antibacterial and DNase-like activity, however, the amount of natural balsamin in Momordica balsamina seeds is limited and preclinical studies require large quantities of pure, bioactive balsamin. Therefore, in this study, we cloned the balsamin gene, expressed it in E.coli BL21 (DE3) strain and purified it by nickel affinity chromatography. Functional analysis indicated that balsamin exhibits both RNA N-glycosidase activity, releasing the Endo-fragment from rabbit reticulocyte rRNA, and DNase-like activity, converting the supercoiled form of a plasmid into the linear form in a concentration-dependent manner. Analysis of secondary structure revealed that recombinant balsamin mainly consisted of α-helical and random coiled with minimal turns and β-sheets. Recombinant balsamin was found to be stable in the temperature range of 20-60 °C and pH range of 6-9. Antimicrobial assays showed that the minimum inhibitory concentrations of recombinant balsamin for various pathogens ranged between 1.56 and 12.5 μg/ml. Heterologous expression and purification of balsamin carries great importance as it provides an alternative approach for large-scale preparation of biologically active recombinant balsamin, which is difficult from its natural source.

History

Journal

International journal of biological macromolecules

Volume

114

Pagination

226 - 234

Publisher

Elsevier

Location

Amsterdam, The Netherlands

ISSN

0141-8130

eISSN

1879-0003

Language

eng

Publication classification

C1 Refereed article in a scholarly journal

Copyright notice

2018, Elsevier B.V.