Molecular and structural characterization of a Bacillus cereus strain producing an anthrax-like capsule

Abstract

This research provides genomic characterization and phylogenetic analysis of a Bacillus cereus strain producing a peptide capsule. Bacteriological techniques confirmed the conditions that induce the production of this capsule. Isolation of the capsule showed that it is high-molecular-weight and proteinase-resistant. The molecular structure of the capsule was characterized using spectroscopic and enantiomeric methods. The results revealed the absence of toxin genes; however, the presence of a poly-γ-glutamic acid (PGA) capsule with a high concentration of D-glutamic acid, akin to the poly-γ-D-glutamic acid (PDGA) capsule produced by B. anthracis , indicates that this strain can be a surrogate for studies of the anthrax PDGA capsule. The findings also contribute to the broader knowledge of B. cereus as a potential biothreat, demanding the development of effective diagnostic, prevention, and treatment measures.