Cobamides, a uniquely diverse family of enzyme cofactors related to vitamin B12, are produced exclusively by bacteria and archaea but used in all domains life. While it is widely accepted that cobamide-dependent organisms require specific cobamides for their metabolism, the biochemical mechanisms make functionally distinct largely unknown. Here, we examine effects cobamide structural variation on model enzyme, methylmalonyl coenzyme A (CoA) mutase (MCM). The vitro binding affinity MCM can be...

ABSTRACT Cobamides, the vitamin B 12 (cobalamin) family of cofactors, are used by most organisms but produced only a fraction prokaryotes, and thus considered key shared nutrients among microbes. Cobamides structurally diverse, with multiple different cobamides found in microbial communities. The ability to use has been tested for several bacteria microalgae, nearly all show preferences certain cobamides. This approach is limited commercial unavailability other than cobalamin. Here, we have...

The beneficial human gut bacterium Akkermansia muciniphila provides metabolites to other members of the microbiota by breaking down host mucin, but most its metabolic functions have not been investigated. A. strain MucT is known use cobamides, vitamin B12 family cofactors with structural diversity in lower ligand. However, unable synthesize cobamides de novo, and specific forms that can be used examined. We found levels growth were nearly identical each seven tested, contrast all bacteria...

Some bacterial mRNAs contain a region called riboswitch which controls gene expression by binding to metabolite in the cell. Typically, riboswitches sense and respond limited range of cellular metabolites, often just one type.

Cobamides, which include vitamin B12 (cobalamin), are a class of modified tetrapyrroles synthesized exclusively by prokaryotes that function as cofactors for diverse biological processes. Cobamides contain centrally bound cobalt ion coordinates to upper and lower axial ligands. The ligand is covalently linked phosphoribosyl moiety through an alpha-glycosidic bond formed the CobT enzyme. can catalyze phosphoribosylation variety substrates. We investigated ability act on either two nitrogen...

Abstract Ruminococcus gnavus is a prevalent human gut commensal bacterium with known roles in intestinal mucus degradation, including by catabolism of the terminal mucin sugar sialic acid. While R. not considered pathogen, overabundance this species correlated Inflammatory Bowel Disease (IBD), and its acid metabolism may play role dysbiotic state. Interestingly, liberation mucin-bound yields distinct product 2,7-anhydro- N -acetylneuraminic (2,7-anhydro-Neu5Ac), contrast to other...

Psychrophilic organisms play a significant role in global nutrient cycling and bioremediation, thus there is great interest understanding the details of their cellular processes. Here, we report first electrochemical measurements cytochrome c552 isolated from model psychrophile, Colwellia psychrerythraea. Quasi-reversible redox behavior observed at thiol-modified bare gold electrodes with midpoint potentials 247 277 mV vs SHE, respectively. Comparison voltammetric response on two substrates...

Abstract Cobamides, the vitamin B 12 (cobalamin) family of cofactors, are used by most organisms but produced only a fraction prokaryotes, and thus considered key shared nutrients among microbes. Cobamides structurally diverse, with multiple different cobamides found in microbial communities. The ability to use has been tested for several bacteria microalgae, nearly all show preferences certain cobamides. This approach is limited commercial unavailability other than cobalamin. Here, we have...

Abstract Cobalamin, commonly known as vitamin B 12 , is an essential micronutrient for humans because of its role enzyme cofactor. Cobalamin one over a dozen structurally related compounds – cobamides that are found in food and produced by microorganisms the human gut. Very little about how different affect -dependent metabolism cells. Here, we test vitro diverse cobamide cofactors function methylmalonyl-CoA mutase (MMUT), two cobalamin-dependent enzymes humans. We find that, although...

Abstract Cobamides, a uniquely diverse family of enzyme cofactors related to vitamin B 12 , are produced exclusively by bacteria and archaea but used in all domains life. While it is widely accepted that cobamide-dependent organisms require specific cobamides for their metabolism, the biochemical mechanisms make functionally distinct largely unknown. Here, we examine effects cobamide structural variation on model enzyme, methylmalonyl-CoA mutase (MCM). The vitro binding affinity MCM can be...

The article assesses results of a study the indices humoral immunity in blood serum and synovial fluid pathomorphological analysis membrane patients with proven diagnosis rheumatoid arthritis (synovitis) knee joint, who underwent synovectomy use arthroscopic technique. A relationship between examined parameters was established indications for joint at early stages disease were substantiated.

Abstract The beneficial human gut bacterium Akkermansia muciniphila provides metabolites to other members of the microbiota by breaking down host mucin, but most its metabolic functions have not been investigated. A. is known use cobamides, vitamin B 12 family cofactors with structural diversity in lower ligand, though specific cobamides it can examined. We found that growth strain Muc T was nearly identical each seven tested, contrast all bacteria studied. Unexpectedly, this promiscuity due...

Abstract In bacteria, many essential metabolic processes are controlled by riboswitches, gene regulatory RNAs that directly bind and detect metabolites. Highly specific effector binding enables riboswitches to respond a single biologically relevant metabolite. Cobalamin potential exception because over dozen chemically similar but functionally distinct cobalamin variants (corrinoid cofactors) exist in nature. Here, we measured riboswitch activity vivo using Bacillus subtilis fluorescent...