Protein Family Models

Date:

2024-08-14

Date:

2024-08-14

This domain is present in cGMP-specific phosphodiesterases, adenylyl and guanylyl cyclases, phytochromes, FhlA and NifA. Adenylyl and guanylyl cyclases catalyse ATP and GTP to the second messengers cAMP and cGMP, respectively, these products up-regulating catalytic activity by binding to the regulatory GAF domain(s). The opposite hydrolysis reaction is catalysed by phosphodiesterase. cGMP-dependent 3',5'-cyclic phosphodiesterase catalyses the conversion of guanosine 3',5'-cyclic phosphate to guanosine 5'-phosphate. Here too, cGMP regulates catalytic activity by GAF-domain binding. Phytochromes are regulatory photoreceptors in plants and bacteria which exist in two thermally-stable states that are reversibly inter-convertible by light: the Pr state absorbs maximally in the red region of the spectrum, while the Pfr state absorbs maximally in the far-red region. This domain is also found in FhlA (formate hydrogen lyase transcriptional activator) and NifA, a transcriptional activator which is required for activation of most Nif operons which are directly involved in nitrogen fixation. NifA interacts with sigma-54. This domain can bind biliverdine and phycocyanobilin (Matilla et al., FEMS Microbiology Reviews, fuab043, 45, 2021, 1. https://doi.org/10.1093/femsre/fuab043). Discovery and naming of the GAF domain. [1]. 9433123. The GAF domain: an evolutionary link between diverse phototransducing proteins. Aravind L, Ponting CP;. Trends Biochem Sci 1997;22:458-459. [2]. 20004158. Cyclic nucleotide binding GAF domains from phosphodiesterases: structural and mechanistic insights. Heikaus CC, Pandit J, Klevit RE;. Structure. 2009;17:. TRUNCATED at 1650 bytes (from Pfam)

Date:

2024-10-16

Date:

2024-08-14

The PAS fold corresponds to the structural domain that has previously been defined as PAS and PAC motifs [4]. The PAS fold appears in archaea, eubacteria and eukarya. This domain can bind gases (O2, CO and NO), FAD, 4-hydroxycinnamic acid and NAD+ (Matilla et.al., FEMS Microbiology Reviews, fuab043, 45, 2021, 1. https://doi.org/10.1093/femsre/fuab043). [1]. 9301332. PAS domain S-boxes in archaea, bacteria and sensors for oxygen and redox. Zhulin IB, Taylor BL, Dixon R;. Trends Biochem Sci 1997;22:331-333. [2]. 7756254. 1.4 A structure of photoactive yellow protein, a cytosolic photoreceptor: unusual fold, active site, and chromophore. Borgstahl GE, Williams DR, Getzoff ED;. Biochemistry 1995;34:6278-6287. [3]. 9382818. PAS: a multifunctional domain family comes to light. Ponting CP, Aravind L;. Curr Biol 1997;7:674-677. [4]. 15009198. The PAS fold: a redefination of the PAS domain based upon structural prediction. Hefti MH, Francoijs KJ, de Vries SC, Dixon R, Vervoort J;. Eur J Biochem 2004;271:1198-1208. (from Pfam)

Date:

2024-10-16

Positively regulates the dhaKLM operon from a sigma-70 promoter

Gene:

dhaR

Date:

2022-03-31

PTS-dependent dihydroxyacetone kinase operon transcriptional regulator DhaR positively regulates the dhaKLM operon from a sigma-70 promoter

Date:

2019-07-02