Antibacterial activity of antimicrobial peptide extracted from Trianthema portulacastrum Leaves

Multidrug-resistant (MDR) infections have posed a major health threat over the past decades. The presently available antibiotics are unable to work against these MDRs. New strategies are being developed and developing potent antibiotic from antimicrobial protein peptides (AMPPs) can be one of the important strategies to tackle MDRs as an alternative to synthetic antibiotic. AMPPs are the crucial factors that play an important role in host defense mechanisms. Apart from secondary metabolites, plants are the major source of antimicrobial peptides mainly known as plant antimicrobial peptides (PAMPs). PAMPs mainly interact with phospholipids present in the cell wall of microorganisms that lead to membrane permeabilization. The present research work was an attempt to isolate novel antimicrobial peptides (AMPs) from the leaves of Trianthema portulacastrum. These AMPs showed antimicrobial activity against Staphylococcus aureus and Bacillus subtilis whereas no activity was observed against Escherichia coli and Candida albicans. Maximum zone of inhibition of 8mm and 4mm was found with 75% protein pellet against Staphylococcus aureus and Bacillus subtilis respectively. In Tricine SDS-PAGE, three bands lower than 26.6kDa were found in both 25% and 50% protein pellet and four bands were observed in 75% and 90% protein pellets. The antimicrobial peptides lower than 26.6kDa are the putative antimicrobial peptides, which may be used or altered to evolve new antibiotics against drug-resistant microbes.