Degli Esposti M, Arutjunjan A M, Konstantinov A A
Dept of Biology, University of Bologna, Italy.
FEBS Lett. 1989 Aug 28;254(1-2):74-8. doi: 10.1016/0014-5793(89)81012-9.
The CD spectrum of reduced cytochrome (cyt.) beta-561 in chromaffin granule membranes resembles that of mitochondrial cyt. beta 1 and indicates possible heme-heme interaction in the protein. Based on spectroscopic data and analysis of the amino acid sequence, a model of cyt. beta-561 is suggested, in which the protein carries two transmembrane-localized hemes, each coordinated by two histidines. The model accounts for the presence of two different forms of cyt. beta-561 in chromaffin granule membranes and provides a mechanism of transmembrane electron transfer by this hemoprotein.
