Specific potassium ion interactions facilitate homocysteine binding to betaine-homocysteine S-methyltransferase.
Mladkova, J., Hladilkova, J., Diamond, C.E., Tryon, K., Yamada, K., Garrow, T.A., Jungwirth, P., Koutmos, M., Jiracek, J.(2014) Proteins 82: 2552-2564
- PubMed: 24895213 
- DOI: 10.1002/prot.24619
- Primary Citation of Related Structures:  
4M3P - PubMed Abstract: 
Betaine-homocysteine S-methyltransferase (BHMT) is a zinc-dependent methyltransferase that uses betaine as the methyl donor for the remethylation of homocysteine to form methionine. This reaction supports S-adenosylmethionine biosynthesis, which is required for hundreds of methylation reactions in humans ...