Antimicrobial Activity of Actinomycetes Isolated From Hot Springs in Western Uganda

Actinomycetes are Gram-positive filamentous bacteria belonging to the phylum Actinobacteria. This study aimed to isolate and characterize Actinomycetes from Ugandan hot springs and evaluate their antimicrobial activity against pathogenic microorganisms.

A total of 30 Actinomycetes isolates were retrieved from two major hot springs in Uganda and identified using morphological and molecular techniques, including PCR amplification of the 16S rRNA gene and whole-genome sequencing. Antimicrobial activity was assessed against Staphylococcus aureus, Escherichia coli, and Candida species using cross-streak and agar well diffusion methods.

Out of the 30 Actinomycetes isolates, 15 (50%) exhibited antimicrobial activity against at least one of the test pathogens; six isolates (20%) exhibited antibacterial activity against Gram-negative bacteria, four isolates (13.3%) showed activity against Gram-negative bacteria, while five isolates (16.7%) showed activity against Candida isolates. HB003 and HB026 were the most potent isolates against Gram-negative and Gram-positive isolates, respectively. Upon comprehensive full-genome analysis using the PATRIC software system (Virginia Bioinformatics Institute, Blacksburg, USA), the annotations of all the isolates were identified as Actinomycete sp.

This study emphasizes the potential of Actinomycetes from hot springs in Uganda as promising sources of bioactive compounds for developing drugs against pathogenic microorganisms, addressing the global threat of drug resistance.