Results 41 to 50 of about 1,347 (167)

An Investigation into the Relationship Between Adenine Modification and Cobamide Lower Base Synthesis [PDF]

, 2023
Cobalamin, also known as vitamin B12 is a widely used cofactor in cellular metabolism but is only synthesized in a few species of prokaryotes. Interestingly, cobalamin in the large intestine is not bioavailable.
Mhlongo, Khethile
core   +1 more source

Structural Investigation of the Biosynthesis of Alternative Lower Ligands for Cobamides by Nicotinate Mononucleotide: 5,6-Dimethylbenzimidazole Phosphoribosyltransferase from Salmonella enterica *

Journal of Biological Chemistry, 2001
Nicotinate mononucleotide (NaMN):5,6-dimethylbenzimidazole phosphoribosyltransferase (CobT) from Salmonella enterica plays a central role in the synthesis of α-ribazole, a key component of the lower ligand of cobalamin.
C. Cheong, J. Escalante-Semerena, I. Rayment   +2 more
semanticscholar   +1 more source

Cobalt Resistance via Detoxification and Mineralization in the Iron-Reducing Bacterium Geobacter sulfurreducens

Frontiers in Microbiology, 2020
Bacteria in the genus Geobacter thrive in iron- and manganese-rich environments where the divalent cobalt cation (CoII) accumulates to potentially toxic concentrations.
Hunter Dulay, Marcela Tabares, Kazem Kashefi, Gemma Reguera   +3 more
doaj   +1 more source

Cobamides and ribonucleotide reduction. VI. Enzyme-catalyzed hydrogen exchange between water and deoxyadenosylcobalamin.

Journal of Biological Chemistry, 1968
When deoxyadenosylcobalamin was incubated with ribonucleoside triphosphate reductase from Lactobacillus leichmannii, dihydrolipoate, and a nucleoside triphosphate in the presence of tritiated water, labeled hydrogen was incorporated into nonexchangeable ...
H. Hogenkamp, R. Ghambeer, C. Brownson, Raymond L. Blakley, E. Vitols   +4 more
semanticscholar   +1 more source

Analysis of Substrate Specificity in CobT Homologs Reveals Widespread Preference for DMB, the Lower Axial Ligand of Vitamin B12 [PDF]

, 2013
SummaryCobamides such as vitamin B12 (cobalamin) are produced exclusively by prokaryotes and used by many other organisms as cofactors for diverse metabolic processes. Cobamides are cobalt-containing tetrapyrroles with upper and lower axial ligands.
Tran, Jennifer L.A., Taga, Michiko E., Hazra, Amrita B., Crofts, Terence S.   +3 more
core   +1 more source

Flexible Cobamide Metabolism in Clostridioides (Clostridium) difficile 630 Δerm. [PDF]

, 2020
Clostridioides (Clostridium) difficile is an opportunistic pathogen known for its ability to colonize the human gut under conditions of dysbiosis. Several aspects of its carbon and amino acid metabolism have been investigated, but its cobamide (vitamin ...
Shelton, Amanda N, Lyu, Xun, Taga, Michiko E   +2 more
core   +1 more source

Ethanolamine deaminase, a cobamide coenzyme-dependent enzyme. II. Physical and chemical properties and interaction with cobamides and ethanolamine.

Journal of Biological Chemistry, 1968
A purified preparation of clostridial ethanolamine deaminase was shown to be homogeneous by sedimentation in the ultracentrifuge and by disc gel electrophoresis.
Barry H. Kaplan, E. R. Stadtman
semanticscholar   +1 more source

Nonnative Thiol and Aniline Methylation, Including Enantioselective Dithiol Desymmetrization, by Multicomponent Cobamide‐Dependent Methyltransferases Using Unactivated Methyl Donors

Angewandte Chemie International Edition, EarlyView.
Mixed MtaABC/MtgABC methyltransferase systems were developed for non‐native thiol and aniline methylation using the unactivated methyl donors methanol and glycine betaine. The platform enabled site‐selective and enantioselective methylation with turnover number up to 6000, representing the first enantioselective non‐native catalysis by cobamide ...
Amardeep Kumar, Osman Ishag Adam, Paras Gupta, Jared C. Lewis   +3 more
wiley   +1 more source

Solution Structural Studies of GTP:Adenosylcobinamide-Phosphateguanylyl Transferase (CobY) from Methanocaldococcus jannaschii.

PLoS ONE, 2015
GTP:adenosylcobinamide-phosphate (AdoCbi-P) guanylyl transferase (CobY) is an enzyme that transfers the GMP moiety of GTP to AdoCbi yielding AdoCbi-GDP in the late steps of the assembly of Ado-cobamides in archaea.
Kiran K Singarapu, Michele M Otte, Marco Tonelli, William M Westler, Jorge C Escalante-Semerena, John L Markley   +5 more
doaj   +1 more source

Bridging Liquid and Gas Phase Catalysis for Abiotic CO2 Conversion to Prebiotic Organics Over Mesoporous Silica‐Supported Ni–Co Catalysts

Advanced Synthesis &Catalysis, Volume 368, Issue 11, 3 June 2026.
Under simulated hydrothermal vent conditions, Ni⋅Co bimetallic catalysts supported on silica convert CO2 and H2O into key metabolites such as formate, methanol, and ethanol. Water plays a critical role in CO2 adsorption and product selectivity, shaping catalytic performance across both liquid and gas phases.
Yingrui Zhao, Nicholas F. Dummer, Kieran J. Aggett, Graham J. Hutchings, William F. Martin, Harun Tüysüz   +5 more
wiley   +1 more source