Fig. 1: Microcystin structure, the reaction catalyzed by McyI, and phylogenetic tree of the 2HADH family.
From: Structural insights into the catalytic mechanism of the microcystin tailoring enzyme McyI

A The MeAsp moiety within microcystin. B Interconversion of 3-methylmalate and MeOAA by removing/adding a hydrogen to the 2-hydroxyl/2-oxo group. C Phylogenetic tree of the 2HADH family members. The prefix abbreviations are: Hs, Homo sapiens, Mt Mycobacterium tuberculosis, Ph Pyrococcus horikoshii, As Anabaena sp. 90, Ns Nostoc sp. 152, Cb Candida boidinii, Sa Staphylococcus aureus, Hm Hyphomicrobium methylovorum, Pf Pyrococcus furiosus, Tt Thermus thermophiles, Aa Aquifex aeolicus, Tp Treponema pallidum, Ld Lactobacillus delbrueckii.