链霉菌TRM74023的基因簇分析及其抑菌活性OA

Staphylococcus aureus is a pathogenic bacterium responsible for food-borne infections.The overuse of antibiotics has led to a lack of effective pharmacological treatments for S.aureus infection.To identify candidate therapeutic agents,the metabolic potential and active components of Streptomyces strain TRM74023 were analyzed.Metabolic potential was comprehensively assessed based on a genomic analysis,and antibacterial activity was analyzed by adopting SS.aureus as the target bacterium.Biologically active secondary metabolites were obtained through modern techniques for isolation,purification,and identification.The bacterium had a genome size of 6 885 644 bp and a G+C content of 72.24％.The average nucleotide identity(ANI),DNA-DNA hybridization(DDH)values,and phylogenetic analysis collectively suggested that TRM74023 is a novel species.In total,29 natural product biosynthetic gene clusters and three resistance genes were found in Streptomyces strain TRM74023.Two monomeric compounds were isolated based on an antibacterial activity analysis and were identified as actinolactomycin and 6-methylnicotinic acid.Actinolactomycin(1 mg·mL-1)exhibited strong activity against SS.aureus,with an inhibition zone diameter of 21.40 mm and MIC and MBC values of 1×10-3mg·mL-1and 1×10-2mg·mL-1,respectively.Significant antibacterial effects were detected against Enterococcus faecalis,Acinetobacter baumannii,and Erwinia amylovora.In summary,Streptomyces strain TRM74023 demonstrated substantial metabolic potential,and actinolactomycin isolated from the bacterium exhibited strong antibacterial effects against S.aureus.These results can serve as a scientific basis for the development of drugs to prevent and control food-borne pathogenic bacteria,such as S.aureus.