Cofactor (biochemistry)

The succinate dehydrogenase complex showing several cofactors, including flavin, iron–sulfur centers, and heme.
A simple [Fe2S2] cluster containing two iron atoms and two sulfur atoms, coordinated by four protein cysteine residues.
The redox reactions of nicotinamide adenine dinucleotide.

Non-protein chemical compound or metallic ion that is required for an enzyme's role as a catalyst .

- Cofactor (biochemistry)
The succinate dehydrogenase complex showing several cofactors, including flavin, iron–sulfur centers, and heme.

44 related topics

Alpha

A 1990 phylogenetic tree linking all major groups of living organisms to the LUCA (the black trunk at the bottom), based on ribosomal RNA sequence data.

Last universal common ancestor

Most recent population of organisms from which all organisms now living on Earth have a common descent—the most recent common ancestor of all current life on Earth.

Most recent population of organisms from which all organisms now living on Earth have a common descent—the most recent common ancestor of all current life on Earth.

A 1990 phylogenetic tree linking all major groups of living organisms to the LUCA (the black trunk at the bottom), based on ribosomal RNA sequence data.
LUCA systems and environment
2005 tree of life showing horizontal gene transfers between branches, giving rise to an interconnected network rather than a tree
The LUCA used the Wood–Ljungdahl or reductive acetyl–CoA pathway to fix carbon.

The cofactors also reveal "dependence upon transition metals, flavins, S-adenosyl methionine, coenzyme A, ferredoxin, molybdopterin, corrins and selenium. Its genetic code required nucleoside modifications and S-adenosylmethionine-dependent methylations."

Bacillus stearothermophilus adenylate kinase

Adenylate kinase

Phosphotransferase enzyme that catalyzes the interconversion of the various adenosine phosphates (ATP, ADP, and AMP).

Phosphotransferase enzyme that catalyzes the interconversion of the various adenosine phosphates (ATP, ADP, and AMP).

Bacillus stearothermophilus adenylate kinase
PDB image 3HPQ showing the ADK enzyme skeleton in cartoon and the key residues as sticks and labeled according to their placement in E. coli, crystallized with Ap5A inhibitor.
Residues of ADKE. coli involved in substrate binding
Describes the generic kinetic cycle of the ADK enzyme family. Ternary complex is labeled.

A magnesium cofactor is also required, essential for increasing the electrophilicity of the phosphate on AMP, though this magnesium ion is only held in the active pocket by electrostatic interactions and dissociates easily.

The succinate dehydrogenase complex showing several cofactors, including flavin, iron–sulfur centers, and heme.

Tryptophan tryptophylquinone

The succinate dehydrogenase complex showing several cofactors, including flavin, iron–sulfur centers, and heme.

Tryptophan tryptophylquinone (TTQ) is an enzyme cofactor, generated by posttranslational modification of amino acids within the protein.

structure of a hyperthermophilic tungstopterin enzyme, aldehyde ferredoxin oxidoreductase

Aldehyde ferredoxin oxidoreductase

Aldehyde ferredoxin oxidoreductase is an enzyme that catalyzes the chemical reaction

Aldehyde ferredoxin oxidoreductase is an enzyme that catalyzes the chemical reaction

structure of a hyperthermophilic tungstopterin enzyme, aldehyde ferredoxin oxidoreductase
Molybdopterin cofactor, shown in the dithiol protonation state.
AOR mechanism at the active site.

The active site of the AOR family feature an oxo-tungsten center bound to a pair of molybdopterin cofactors (which does not contain molybdenum) and an 4Fe-4S cluster.