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A derivative of vitamin B12; its impaired biosynthesis can lead to methylmalonic acidemia.
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
Adenosylcobalamin and Methylcobalamin are B12 vitamers that may be more effective than Cyanocobalamin.
The cblD defect causes either isolated or combined deficiency of methylcobalamin and adenosylcobalamin synthesis.
To create this novel hydrogel, the team assembled genetically-engineered proteins into molecular networks by stitching together the photoreceptor C-terminal adenosylcobalamin binding domain (CarHC) proteins at room temperature.
Adenosylcobalamin (AdoCbl) and methylcobalamin (MeCbl) are cofactors for these 2 enzymes.
Cobalamin C (cblC) disease is the most common type of MMA and is characteristically concurrent with homocystinemia (HCY) due to impaired synthesis of two active forms of cbl, namely adenosylcobalamin (AdoCbl) and methylcobalamin (MeCbl).
Cobalamin exists in four forms: hydroxocobalamin, methylcobalamin, cyanocobalamin, and adenosylcobalamin. Methylcobalamin and adenosylcobalamin are biologically active forms of cobalamin [10] whereas hydroxocobalamin and cyanocobalamin are inactive.
* Supplement with: 500 mcg of vitamin B12* (look for methylcobalamin and adenosylcobalamin, the most active forms).
There are numbers of naturally occurring Cbl species in the human body, but only methylcobalamin (MeCbl) and adenosylcobalamin (AdoCbl) are biologically active, meaning that only they directly act as enzyme cofactors.
Cobalamin is used to denote the structure of a corrin nucleus; methylcobalamin and adenosylcobalamin act as cofactors in the body, while the others are therapeutic methods of food consumption.
The biologically active coenzyme forms of vitamin B12 that play a role in human metabolism are methylcobalamin and 5-deoxyadenosylcobalamin (commonly known as adenosylcobalamin).
Vitamin B12 has some analogs including cyanocobalamin (CNCbl), methylcobalamin (MeCbl), hydroxocobalamin (OHCbl), and adenosylcobalamin (AdoCbl).
Yet, these two Cbl-dependent enzymes, cytosolic methionine synthase (MS) [EC], requiring methylcobalamin (MeCbl), and mitochondrial methylmalonyl-CoA mutase (MU) [EC], requiring adenosylcobalamin (AdoCbl) [1, 2], are critically involved in key metabolic pathways essential for gene expression and regulation, via formation of S-adenosylmethionine (SAM) and methylation, and in protein synthesis and catabolism, cellular respiration, and energy.