Abstract
Following the complete sequencing of the genome of the univellular cyanobacterium, Synechocystis sp. strain PCC6803, within our institute, a protein‐gene linkage map of this photosynthetic microorganism was successfully constructed for 130 high abundance proteins present on two‐dimensional gels. An additional six proteins were analyzed, but were probably encoded extrachromosomally. In order to demonstrate the usefulness of this protein‐gene linkage map, we analyzed the changes that occur in cellular proteins after illumination of PCC6803 cells. The results indicate that this protein‐gene linkage map greatly simplifies the identification process of such modulated genes. After illumination, at least three distinctive spots with reduced intensity were detected on two‐dimensional gels and the corresponding genes of two of these were successfully identified as chaperonin 2 and a Tortula ruralis rehydrin‐related gene. Thus, the combination of the protein‐gene linkage map and two‐dimensional gel electrophoresis should permit a comprehensive analyses of the proteins encoded by the genome (i.e., “proteome”) of this photosynthetic autotroph. This post‐genome project represents a productive way of exploiting the information obtained from the sequencing of the cyanobacterium genome.