Genomic and phenotypic diversities among Bacillus cereus isolates from cosmetics

Area of Science:

• Microbiology
• Genomics
• Antimicrobial Resistance

Background:

• Bacillus cereus poses risks to product safety and quality.
• Genomic analysis of a B. cereus cosmetic isolate (3 A ES) revealed adaptation genes.
• Comparative study of cosmetic and non-cosmetic B. cereus strains.

Purpose of the Study:

• Compare genotypic and phenotypic resistance of B. cereus strains.
• Investigate traits of B. cereus isolates from cosmetic products.
• Determine factors influencing antimicrobial resistance in B. cereus.

Main Methods:

• Whole-genome sequencing and phylogenetic analysis using BTyper and BV-BRC (PATRIC).
• Phenotypic testing of antibiotic and biocide resistance using Vitek 2 Compact and phenotype microarrays.
• Statistical analysis to compare growth and resistance profiles.

Main Results:

• BTyper classified strains into phylogenetic groups, with B. pumilus as an outlier.
• Genomic analysis identified genes conferring resistance to antibiotics and biocides.
• Significant differences in overall sensitivity/resistance phenotypes observed; 3 A ES was most resistant, ATCC 7061 least resistant.
• No significant difference in average growth/respiration between cosmetic and non-cosmetic isolates (p=0.56).

Conclusions:

• B. cereus strains exhibit diverse genotypic and phenotypic profiles.
• No specific traits distinguish cosmetic B. cereus isolates from non-cosmetic ones.
• Antimicrobial resistance is influenced by both the strain's genetic resistance arsenal and the antibiotic concentration.