AnCrpA, a cAMP receptor protein, regulates nif-related gene expression in the cyanobacterium Anabaena sp. strain PCC 7120 grown with nitrate.
Target genes for a cAMP receptor protein, AnCrpA, were screened using an Anabaena oligonucleotide microarray and real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) analysis. Several gene expressions, including some involved in nitrogen fixation, were downregulated in the ancrpA disruptant when cells were grown with nitrate. Electrophoretic mobility shift assays (EMSAs) revealed that AnCrpA bound to the 5' upstream region of nifB, all1439, hesA, all5347, hglE and coxBII in the presence of cAMP, and all of them are related with nitrogen fixation. A possible AnCrpA-binding site in the 5' upstream region of nifB was predicted using hidden Markov model (HMM) software based on the result of in vitro selection of AnCrpA-binding sequences, and the binding was confirmed by EMSA. Thus, AnCrpA regulates the expressions of gene clusters related to nitrogen fixation in the presence of nitrate.
Suzuki
Takayuki
T
Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Japan.
Yoshimura
Hidehisa
H
Ehira
Shigeki
S
Ikeuchi
Masahiko
M
Ohmori
Masayuki
M
D017033:Anabaena / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D000242:Cyclic AMP / Q000378:metabolism / Q000494:pharmacology; D002373:Cyclic AMP Receptor Protein / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects / Q000502:physiology*; D008390:Markov Chains; D008957:Models, Genetic; D005810:Multigene Family / Q000502:physiology; D009566:Nitrates / Q000494:pharmacology; D009586:Nitrogen Fixation / Q000187:drug effects / Q000502:physiology*; D011485:Protein Binding; D050436:Regulatory Elements, Transcriptional / Q000502:physiology*; D012984:Software
D001426:Bacterial Proteins; D002373:Cyclic AMP Receptor Protein; C092498:NifB protein, Bacteria; D009566:Nitrates; D000242:Cyclic AMP