Summary: Shigella is the etiological agent of shigellosis. Antimicrobial peptides and proteins are biologically active substances produced by prokaryotes and eukaryotes that may present antagonistic activity against a wide range of microorganism. In this study, the intracellular extract of a Shigella sonnei isolate was precipitated with 75% ammonium sulfate and purified by sequential chromatography steps using ion exchange, molecular exclusion, and reversed-phase columns. Analysis by mass spectrometry identified three substances with molecular masses of 7.2, 9.2 and 10.7 kDa, active against another Shigella sonnei isolate. The amino acid sequences of the active substances were evaluated with the aid of BLAST - P software. The antagonistic substances were identified, respectively, as 50S ribosomal protein L29 of Escherichia coli, DNA-binding protein HU-beta and ribosome hibernation promoting factor both of Shigella sonnei. Data demonstrated that Shigella sonnei synthesizes three antimicrobial substances that present other classical functions, active against another isolate of the same species.

Publication year: 2022

Types of publication: Journal article

Unit: Embrapa Dairy Cattle