Functional Characterization of the Gene Encoding UDP-glucose: Tetrahydrobiopterin α-Glucosyltransferase in Synechococcus sp. PCC 7942

In this study, we attempted to characterize the Synechococcus sp. PCC 7942 mutant resultant from a disruption in the gene encoding UDP-glucose: tetrahydrobiopterin α-glucosyltransferase (BGluT). 2D-­PAGE followed by MALDI-TOF mass spectrometry revealed that phycocyanin rod linker protein 33K was one of the proteins expressed at lower level in the BGluT mutant. BGluT mutant cells were also determined to be more sensitive to high light stress. This is because photosynthetic O₂ exchange rates were significantly decreased, due to the reduced number of functional PSIs relative to the wild type cells.