Evolutionary origin and functional diversification of aminotransferases.
J Biol Chem
; 298(8): 102122, 2022 08.
Article
in En
| MEDLINE
| ID: mdl-35697072
ABSTRACT
Aminotransferases (ATs) are pyridoxal 5'-phosphate-dependent enzymes that catalyze the transamination reactions between amino acid donor and keto acid acceptor substrates. Modern AT enzymes constitute â¼2% of all classified enzymatic activities, play central roles in nitrogen metabolism, and generate multitude of primary and secondary metabolites. ATs likely diverged into four distinct AT classes before the appearance of the last universal common ancestor and further expanded to a large and diverse enzyme family. Although the AT family underwent an extensive functional specialization, many AT enzymes retained considerable substrate promiscuity and multifunctionality because of their inherent mechanistic, structural, and functional constraints. This review summarizes the evolutionary history, diverse metabolic roles, reaction mechanisms, and structure-function relationships of the AT family enzymes, with a special emphasis on their substrate promiscuity and multifunctionality. Comprehensive characterization of AT substrate specificity is still needed to reveal their true metabolic functions in interconnecting various branches of the nitrogen metabolic network in different organisms.
Key words
Full text:
1
Database:
MEDLINE
Main subject:
Pyridoxal Phosphate
/
Transaminases
Language:
En
Journal:
J Biol Chem
Year:
2022
Type:
Article
Affiliation country:
United States