Endophytic Streptomyces sp. MSARE05 isolated from roots of Peanut plant produces a novel antimicrobial compound.

This article focuses on the isolation and characterization of a novel antimicrobial compound, SM05, produced by the endophytic bacterium Streptomyces sp. MSARE05 from peanut (Arachis hypogaea) roots. SM05, with a molecular weight of 485.54 Dalton and containing a naphthalene moiety, demonstrated inhibitory activity against a range of gram-positive and gram-negative bacteria, including multidrug-resistant (MDR) strains and Mycobacterium smegmatis, with minimum inhibitory concentrations (MIC) between 0.4 and 3.2 µg/ml. The compound disrupts bacterial cell membranes, leading to leakage of intracellular contents, inhibits biofilm formation, and shows synergistic effects when combined with common antibiotics such as ampicillin and chloramphenicol, while exhibiting no cytotoxicity toward human HuH-7 cell lines. These findings highlight the potential of endophytic Streptomyces as a source of new antibiotics to address antimicrobial resistance.