To B12 or not to B12: Five questions on the role of cobalamin in host-microbial interactions
Fig 2
Cobalamin influences pathogenesis at distinct body sites.
Each box shows the pathogens demonstrated to rely on cobalamin-dependent processes to grow and/or regulate virulence during infection. (A) Enterococcus faecalis, Salmonella serovar Typhimurium, and Clostridium difficile are shown in the colon. The localization of each strain in the figure is not representative of specific colonic sites of colonization. (B) Mycobacterium tuberculosis infection of the lung. (C) Propionibacterium acnes colonization of the skin, resulting in an acne pustule on the nose. (D) Listeria monocytogenes and S. Typhimurium bloodstream infection. Bacteria surviving in macrophages are disseminated to the liver and spleen. (E) An increased number of microbiota members in the small intestine can lead to bacteria cobalamin consumption and competition between IF and bacteria for binding to cobalamin. (F) Uropathogenic Escherichia coli colonization of the bladder. IF, intrinsic factor.