Cyanobacterial response regulator PatA contains a conserved N-terminal domain (PATAN) with an alpha-helical insertion.
The cyanobacterium Anabaena (Nostoc) PCC 7120 responds to starvation for nitrogen compounds by differentiating approximately every 10th cell in the filament into nitrogen-fixing cells called heterocysts. Heterocyst formation is subject to complex regulation, which involves an unusual response regulator PatA that contains a CheY-like phosphoacceptor (receiver, REC) domain at its C-terminus. PatA-like response regulators are widespread in cyanobacteria; one of them regulates phototaxis in Synechocystis PCC 6803. Sequence analysis of PatA revealed, in addition to the REC domain, a previously undetected, conserved domain, which we named PATAN (after PatA N-terminus), and a potential helix-turn-helix (HTH) domain. PATAN domains are encoded in a variety of environmental bacteria and archaea, often in several copies per genome, and are typically associated with REC, Roadblock and other signal transduction domains, or with DNA-binding HTH domains. Many PATAN domains contain insertions of a small additional domain, termed alpha-clip, which is predicted to form a four-helix bundle. PATAN domains appear to participate in protein-protein interactions that regulate gliding motility and processes of cell development and differentiation in cyanobacteria and some proteobacteria, such as Myxococcus xanthus and Geobacter sulfurreducens.
Makarova
Kira S
KS
National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
Koonin
Eugene V
EV
Haselkorn
Robert
R
Galperin
Michael Y
MY
D000595:Amino Acid Sequence; D017033:Anabaena / Q000378:metabolism; D018407:Bacterial Physiological Phenomena; D001426:Bacterial Proteins / Q000737:chemistry* / Q000502:physiology*; D002454:Cell Differentiation; D002465:Cell Movement; D019295:Computational Biology / Q000379:methods; D017124:Conserved Sequence; D019077:Helix-Turn-Helix Motifs; D008969:Molecular Sequence Data; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid
D001426:Bacterial Proteins; C075180:PatA protein, Anabaena