Expression of Escherichia coli phosphoenolpyruvate carboxylase in a cyanobacterium. Functional complementation of Synechococcus PCC 7942 ppc.
The gene (ppc) coding for phosphoenolpyruvate carboxylase (PEPCase) in the cyanobacterium Synechococcus PCC 7942 has been inactivated via insertional mutagenesis while being functionally complemented by Escherichia coli ppc. Cyanobacterial cells functionally complemented by E. coli ppc showed decreased PEPCase activity in crude cell lysates and detergent-permeabilized whole cell assays. Decreased rates of growth, reduced levels of chlorophyll a, and decreased photosynthetic O2 evolution capacity per cell when compared to wild-type cyanobacterial cells were also observed. Phycobiliprotein levels were not affected. The results are discussed in terms of the impact of reduced PEPCase activity on cyanobacterial cell metabolism and the regulatory properties of the E. coli gene product.
Luinenburg
I
I
Department of Botany, University of Toronto, Ontario, Canada.
Coleman
J R
JR
D001426:Bacterial Proteins / Q000032:analysis; D015139:Blotting, Southern; D002460:Cell Line; D002734:Chlorophyll / Q000032:analysis; D000077194:Chlorophyll A; D000458:Cyanobacteria / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology*; D005798:Genes, Bacterial; D017343:Genes, Plant; D005816:Genetic Complementation Test; D045342:Light-Harvesting Protein Complexes; D016254:Mutagenesis, Insertional; D010730:Phosphoenolpyruvate Carboxylase / Q000096:biosynthesis* / Q000172:deficiency / Q000235:genetics*; D010788:Photosynthesis / Q000235:genetics; D010940:Plant Proteins / Q000032:analysis; D015183:Restriction Mapping; D014170:Transformation, Genetic
D001426:Bacterial Proteins; D045342:Light-Harvesting Protein Complexes; D010940:Plant Proteins; D002734:Chlorophyll; D010730:Phosphoenolpyruvate Carboxylase; D000077194:Chlorophyll A