title: A TPR-family membrane protein gene is required for light-activated heterotrophic growth of the cyanobacterium Synechocystis sp. PCC 6803.
abstract: The unicellular cyanobacterium Synechocystis sp. PCC6803 can grow heterotrophically in complete darkness, given that a brief period of illumination is supplemented every day (light-activated heterotrophic growth, LAHG), or under very weak (<0.5 micromol m(-2) s(-1)) but continuous light. By random insertion of the genome with an antibiotic resistance cassette, mutants defective in LAHG were generated. In two identical mutants, sll0886, a tetratricopeptide repeat (TPR)-family membrane protein gene, was disrupted. Targeted insertion of sll0886 and three downstream genes showed that the phenotype was not due to a polar effect. The sll0886 mutant shows normal photoheterotrophic growth when the light intensity is at 2.5 micromol m(-2) s(-1) or above, but no growth at 0.5 micromol m(-2) s(-1). Homologs to sll0886 are also present in cyanobacteria that are not known of LAHG. sll0886 and homologs may be involved in controlling different physiological processes that respond to light of low fluence.
authors.affiliation: Institute of Hydrobiology, the Chinese Academy of Sciences, Wuhan, 430072, Hubei, PR China.
authors.forename: Renqiu
authors.initials: R
authors.lastname: Kong
authors.forename: Xudong
authors.initials: X
authors.lastname: Xu
authors.forename: Zhengyu
authors.initials: Z
authors.lastname: Hu
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D003470:Culture Media; D000458:Cyanobacteria / Q000235:genetics / Q000254:growth & development*; D015964:Gene Expression Regulation, Bacterial; D008027:Light; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D015398:Signal Transduction
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D008565:Membrane Proteins