Subtiliin

Subtiliin is a bacteriocin, a type of ribosomally synthesized antimicrobial peptide, produced by Bacillus subtilis. It belongs to the class of lantibiotics, characterized by the presence of unusual amino acids, including lanthionine and methyllanthionine, which are formed by post-translational modifications of cysteine residues. Subtiliin is synthesized as a precursor peptide that undergoes extensive processing, including dehydration, cyclization, and cleavage of a leader peptide, to yield the mature active molecule.

The primary function of subtiliin is to inhibit the growth of closely related bacterial species, acting as a form of chemical warfare within microbial communities. Its spectrum of activity typically includes other Gram-positive bacteria, but it can also exhibit some activity against certain Gram-negative bacteria and yeasts. The mechanism of action involves the disruption of the bacterial cell membrane, leading to leakage of intracellular components and cell death. This disruption is often mediated by the pore-forming ability of subtiliin.

Subtiliin has garnered interest for its potential applications in food preservation and as a therapeutic agent. Its ability to inhibit the growth of foodborne pathogens makes it a candidate for use as a natural food preservative. Furthermore, ongoing research explores its potential as an antibiotic, particularly in combating antibiotic-resistant bacteria, although its narrow spectrum of activity and potential for resistance development are factors that need to be considered. The production of subtiliin by B. subtilis, a generally recognized as safe (GRAS) organism, also contributes to its appeal for various applications.