InterPro domain: IPR004567

This family describes the type II form of pantothenate kinase PanK, characterised from the fungus Emericella nidulans and with similar forms known in several other eukaryotes. It also includes forms from several Gram-positive bacteria suggested to have originated from the eukaryotic form by lateral transfer. It differs in a number of biochemical properties (such as inhibition by acetyl-CoA) from type I PanK enzymes and shows little sequence similarity [ 1 , 2 ].

Pantothenate kinase (PanK or CoaA) catalyses the first step of the universal five step coenzyme A (CoA) biosynthesis pathway. CoA is a ubiquitous and essential cofactor in all living organsims. Pantothenate kinase catalyses the first and rate limiting step in the CoA biosynthetic pathway, which involves transferring a phosphoryl group from ATP to pantothenate, also known as vitamin B5. Three distinct types of pantothenate kinase enzymes have been identified: type I PanK enzymes are typified by the E. coli CoaA protein, type II enzymes are primarily found in eukaryotic organisms whilst type III enzymes have a wider phylogenic distribution and are not feedback inhibited by CoA [ 3 ].

1. Cloning and characterization of a eukaryotic pantothenate kinase gene (panK) from Aspergillus nidulans. J. Biol. Chem. 274, 2014-20
2. Inhibitors of pantothenate kinase: novel antibiotics for staphylococcal infections. Antimicrob. Agents Chemother. 47, 2051-5
3. Structural basis for substrate binding and the catalytic mechanism of type III pantothenate kinase. Biochemistry 47, 1369-80