Reconstitution of Apomyoglobin with Extended Biliverdins.

FERNÁNDEZ, MARCELO; FRYDMAN, ROSALÍA BRYKS DE; BARI, SARA E. ; FRYDMAN, JAIME BENJAMÍN

BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 1992 vol. 183 p. 1209 - 1215

0006-291X

An analysis of the reconstitution of biliverdins with extended conformations andhorse heart apomyoglobin was carried out. Biliverdins with the 5Z-syn, 10Z-syn,15Z-anti and 5Z-anti, 10Z-syn, 15Z-anti conformations, as well as biliverdinswith the Z,Z,Z, all-syn conformation recombined with apomyoglobin. In every casethe P enantiomers were bound in excess to the M enantiomers, with exception ofthe 5-syn, 10-syn, 15-anti biliverdin where the M enantiomer boundpreferentially to the protein. Biliverdins with an anti conformation at the C-10meso bridge did not recombine with the protein. It was concluded that thepresence of a syn conformation at the C-10 methine conferred to the biliverdinthe necessary helicity to fit into the apomyoglobin heme pocket. Thisregioselectivity is of importance in view of the well known analogy between theligand domains of myoglobin and the C-phycocyanins.