The FAPY-DNA glycosylase (Fpg) is required for survival of the cyanobacterium Synechococcus elongatus under high light irradiance.
The gene for the DNA repair enzyme Fpg from Synechococcus elongatus was detected immediately downstream of the photosystem I gene psaE. fpg is likely expressed together with psaE by transcriptional readover while psaE is mostly expressed independently. Segregated psaE and fpg deletion strains were obtained upon insertional inactivation of both genes in S. elongatus. These mutants are viable under photoautotrophic conditions, but fail to grow under high light regimes that likely cause oxidative stress. These high light sensitive phenotypes suggest that the Fpg protein, which has been shown to repair DNA lesions caused by reactive oxygen species in Escherichia coli, may be involved in the photoprotection of cyanobacteria against oxidative damage caused under high irradiance.
Mühlenhoff
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Institut für Klinische Zytobiologie, Klinikum der Philipps-Universität Marburg, Robert-Koch-Strasse 5, D-35037, Marburg, Germany. muehlenh@mailer.uni-marburg.de
D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D000458:Cyanobacteria / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D043382:DNA-Formamidopyrimidine Glycosylase; D029968:Escherichia coli Proteins; D017353:Gene Deletion; D005798:Genes, Bacterial; D008027:Light; D008969:Molecular Sequence Data; D009699:N-Glycosyl Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018384:Oxidative Stress; D010788:Photosynthesis; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics / Q000378:metabolism; D045331:Photosystem I Protein Complex; D017422:Sequence Analysis, DNA
D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D045322:Photosynthetic Reaction Center Complex Proteins; D045331:Photosystem I Protein Complex; D009699:N-Glycosyl Hydrolases; D043382:DNA-Formamidopyrimidine Glycosylase; C468610:DNA-formamidopyrimidine glycosylase, E coli