Abstract
Divinyl chlorophyllide reductase (DVR) is one of the enzymes in the chlorophyll biosynthetic pathway. DVR reduces the vinyl group on the pyrrole ring B to the ethyl group. The DVR gene of Arabidopsis (AtDVR) was identified by the genetics approach. AtDVR homologs were not found in cyanobacteria including Synechocystis sp. PCC6803. Slr1923 was identified as the DVR gene (SyDVR) candidate of Synechocystis sp. PCC6803 by the bioinformatics approach and SyDVR disruptant accumulated divinyl chlorophyll instead of monovinyl chlorophyll. We found that both AtDVR and SyDVR recombinant proteins reduce the vinyl group to the ethyl group, but the reductant of AtDVR and SyDVR were different.
Some cyanobacteria possess AtDVR homolog instead of SyDVR homolog. We examined whether AtDVR homolog in cyanobacteria reduces the vinyl group. Marine Synechococcus WH8102 has AtDVR homolog and the recombinant protein reduced the vinyl group to the ethyl group.
These results showed the presence of two types of DVR in cyanobacteria.
