Comparing Anti-bacterial Activity of ‘Anti-bacterial Proteins’ from Parthenium hysterophorus with Three Antibiotics

A ‘no-antibiotic era’ or ‘pre-antibiotic era’ like situation may occur due to the rapid emergence of drug-resistance in pathogenic microbes, which would be a serious problem for medical sciences. AMPs are a different class of therapeutic molecules, which are produced by almost all the class of living organisms as their innate defence mechanism against microbial pathogens. Due to their multi-modal mechanism of action and very less chance of developing resistance against them the AMPs could be a promising solution against the ‘drug resistance’. Isolation of AMPs is a tedious process; hence it would be appropriate to evaluate the antibacterial activity of total proteins, from any source, before proceeding for isolation of AMPs from it. In present work Parthenium hysterophorus, a common invasive weed was screened for the presence of AMPs in it. Total proteins from this plant were extracted using the ‘Tri-chloro Acetic Acid (TCA)- Acetone’ method. The anti-bacterial activities of ‘AMPs containing Whole proteins extract’ (A-WP) were tested against the bacterial strains: Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus by ‘Agar-well diffusion’ method and ‘Gel-overlay method’. A-WP of P. hysterophorus showed antibacterial activity against all the three bacteria and the maximum activity was observed against P. aeruginosa (13.23±0.29 mm). Gel overlay experiments revealed that the antibacterial activity of the A-WP was due to presence of small sized peptides (AMPs) in it. Further research on isolation and purification of AMPs P. physterophorous may provide the novel AMPs.