A Novel Isoquinoline Bioactive Compound 5-Amino-4-Methoxyisoquinolin-1(2H)-One From Desert Actinobacterium Streptomyces Fragilis Strain Da7-7: Isolation, Characterization, And Molecular Docking Analysis

Abstract

A broad spectrum bioactive compound producing actinobacterium Streptomyces fragilis strain DA7-7 was isolated from the desert soil sample of Riyadh Province, Saudi Arabia. The bioactive compounds were extracted using ethyl acetate, separated, and purified. The purified active compound was characterized and identified as 5-amino-4-methoxyisoquinolin-1(2H)-one (C₁₀H₁₀N₂O₂, 191.07 m/z). The compound possessed the lowest minimum inhibitory concentration 15.6 µg/mL against the pathogenic bacteria Escherichia coli ATCC 10536 and E. coli CIB 008, while 31.32 µg/mL against pathogenic fungus Crytococcus neoformans ATCC 90113. In silico antibacterial mechanism and the preclinical evaluation revealed that 5-amino-4-methoxyisoquinolin-1(2H)-one is able to bind efficiently with Undecaprenyl Diphosphate Synthase (-5.02 kcal/mol) when compared to DNA gyrase-Topoisomerase (-4.82 kcal/mol) and IARS (-4.43 kcal/mol) target proteins. Based on the merits of in vitro antimicrobial potential, in silico antibacterial mechanism, and the preclinical evaluations, the biologically active compound could be used as a commercial antimicrobial drug in the near future for human welfare.