Biotechnological Production of the Recombinant Two-Component Lantibiotic Lichenicidin in a Bacterial Expression System.

Objective: Lantibiotics are a family of bacterial antimicrobial peptides synthesized by ribosomes, that undergo post-translational modification to form lanthionine (Lan) and methyllanthionine (MeLan) residues. Lantibiotics are currently considered promising agents for combating antibiotic-resistant bacterial infections. This paper presents a biotechnological method for obtaining two components of the lantibiotic lichenicidin from Bacillus licheniformis B-511, Lchα and Lchβ. Such a system has the potential to facilitate the production of not only lichenicidin, but also other lantibiotics, including two-component ones, and also to enable the study of their biosynthesis and the activity and substrate specificity of modifying enzymes. Methods: The developed system is based on heterologous coexpression of the genes of Lchα and Lchβ precursors with the genes of their corresponding modifying enzymes in the cytoplasm of Escherichia coli BL21(DE3). Subsequent steps included immobilized metal affinity chromatography of the His-tagged hybrid peptide under denaturing conditions, cyanogen bromide cleavage in acidic medium, and final purification using reverse-phase HPLC. Results and Discussion: The system was employed for the expression and purification of lantibiotics, resulting in the successful isolation of the β-component of lichenicidin in high yield (approximately 4 mg/L of culture). This purified beta component exhibited structural and functional characteristics comparable to its natural counterpart, which was purified from the natural producer. However, the yield of the mature α-component of lichenicidin in such a system was significantly lower. Conclusions: The work presents a biotechnological method for obtaining recombinant two-component lantibiotic lichenicidin, which has proven to be particularly effective in the case of Lchβ. The developed method can also be applied to the production of other promising lantibiotics and their further research. [ABSTRACT FROM AUTHOR]