Trogen G B, Edlund U, Larsson G, Sethson I
Department of Organic Chemistry, Umeå University, Sweden.
Eur J Biochem. 1998 Dec 1;258(2):301-12. doi: 10.1046/j.1432-1327.1998.2580301.x.
The microcystin-RR structures are compared with the structures of microcystin-LR in solution as well as in the crystal structure of the complex with protein phosphatase. The gross structures of the two peptides are similar, but with a more accentuated and compact saddle structure for microcystin-RR. The structural differences affect the hydrogen-bond pattern in the peptides and the location of the side chain of N-methyldehydroalanine, both of which are important for the ability of the peptide to form a tight complex with protein phosphatase. These structural differences may contribute to the observed differences in toxicity of microcystin-RR and microcystin-LR.
