close-up of rod-d bacillus bacteria, common in nature and bodies. versatile microbes, some beneficial, others cause diseases

bacteria bacillus rodshaped microscopic grampositive endospores aerobic anaerobic soil water skin gut ubiquitous pathogenic opportunistic spores resistant enzymes bio films chains motile flagella subtilis anthracite cereus foodpoisoning anthrax contamination infection antibiotics probiotics microbiome symbiotic environmental industrial fermentation toxins catalase protease amylase surfactins mycosubtilins antimicrobial sporulation cellwall peptidoglycan teichoic teichuronic