Comparative Analysis of Corrinoid Profiles across Host-Associated and Environmental Samples.

Vitamin B (the cyanated form of cobalamin cofactors) is best known for its essential role in human health. In addition to its function in human metabolism, cobalamin also plays important roles in microbial metabolism and can impact microbial community function. Cobalamin is a member of the structurally diverse family of cofactors known as cobamides that are produced exclusively by certain prokaryotes.

Uneven distribution of cobamide biosynthesis and dependence in bacteria predicted by comparative genomics.

The vitamin B family of cofactors known as cobamides are essential for a variety of microbial metabolisms. We used comparative genomics of 11,000 bacterial species to analyze the extent and distribution of cobamide production and use across bacteria. We find that 86% of bacteria in this data set have at least one of 15 cobamide-dependent enzyme families, but only 37% are predicted to synthesize cobamides de novo.

Nutrient cross-feeding in the microbial world.

The stability and function of a microbial community depends on nutritional interactions among community members such as the cross-feeding of essential small molecules synthesized by a subset of the population. In this review, we describe examples of microbe-microbe and microbe-host cofactor cross-feeding, a type of interaction that influences the forms of metabolism carried out within a community. Cofactor cross-feeding can contribute to both the health and nutrition of a host organism, the virulence and persistence of pathogens, and the composition and function of environmental communities.

Identification of specific corrinoids reveals corrinoid modification in dechlorinating microbial communities.

Cobalamin and other corrinoids are essential cofactors for many organisms. The majority of microbes with corrinoid-dependent enzymes do not produce corrinoids de novo, and instead must acquire corrinoids produced by other organisms in their environment. However, the profile of corrinoids produced in corrinoid-dependent microbial communities, as well as the exchange and modification of corrinoids among community members have not been well studied.

Sustainable growth of Dehalococcoides mccartyi 195 by corrinoid salvaging and remodeling in defined lactate-fermenting consortia.

Corrinoids are essential cofactors of reductive dehalogenases in Dehalococcoides mccartyi, an important bacterium in bioremediation, yet sequenced D. mccartyi strains do not possess the complete pathway for de novo corrinoid biosynthesis. Pelosinus sp.

Cobamide structure depends on both lower ligand availability and CobT substrate specificity.

Cobamides are members of the vitamin B12 family of cofactors that function in a variety of metabolic processes and are synthesized only by prokaryotes. Cobamides produced by different organisms vary in the structure of the lower axial ligand. Here we explore the molecular factors that control specificity in the incorporation of lower ligand bases into cobamides.

Versatility in corrinoid salvaging and remodeling pathways supports corrinoid-dependent metabolism in Dehalococcoides mccartyi.

Corrinoids are cobalt-containing molecules that function as enzyme cofactors in a wide variety of organisms but are produced solely by a subset of prokaryotes. Specific corrinoids are identified by the structure of their axial ligands. The lower axial ligand of a corrinoid can be a benzimidazole, purine, or phenolic compound.