Theoretical study on the thermodynamic properties of chlorophyll d-peptides coordinating ligand.
The chlorophyll d containing cyanobacterium, Acaryochloris marina has provided a model system for the study of chlorophyll replacement in the function of oxygenic photosynthesis. Chlorophyll d replaces most functions of chlorophyll a in Acaryochloris marina. It not only functions as the major light-harvesting pigment, but also acts as an electron transfer cofactor in the primary charge separation reaction in the two photosystems. The Mg-chlorophyll d-peptide coordinating interaction between the amino acid residues and chlorophylls using the latest semi-empirical PM5 method were examined. It is suggested that chlorophyll d possesses similar coordination ligand properties to chlorophyll a, but chlorophyll b possesses different ligand properties. Compared with other studies involving theoretical correlation and our prior experiments, this study suggests that the chlorophyll a-bound proteins will bind chlorophyll d without difficulty when chlorophyll d is available.
Chen
Min
M
School of Biological Sciences, The University of Sydney, NSW 2006, Australia. minchen@bio.usyd.edu.au
Cai
Zheng-Li
ZL
D002734:Chlorophyll / Q000737:chemistry* / Q000378:metabolism; D000458:Cyanobacteria / Q000737:chemistry; D008024:Ligands; D008956:Models, Chemical; D015394:Molecular Structure; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism; D013816:Thermodynamics
D008024:Ligands; D010455:Peptides; D002734:Chlorophyll; C107509:chlorophyll d