Protein Family Models

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. [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

This family represents the structurally related ATPase domains of histidine kinase, DNA gyrase B and HSP90. [1]. 18361456. Crystal structure of a novel non-Pfam protein AF1514 from Archeoglobus fulgidus DSM 4304 solved by S-SAD using a Cr X-ray source. Li Y, Bahti P, Shaw N, Song G, Chen S, Zhang X, Zhang M, Cheng C, Yin J, Zhu JY, Zhang H, Che D, Xu H, Abbas A, Wang BC, Liu ZJ;. Proteins 2008;71:2109-13. (from Pfam)

Date:

2024-10-16

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

Phytochromes are red/far-red photochromic biliprotein photoreceptors which regulate plant development. They are widely represented in both photosynthetic and non-photosynthetic bacteria and are known in a variety of fungi. Although sequence similarities are low, this domain is structurally related to Pfam:PF01590 [1], which is generally located immediately N-terminal to this domain. Compared with Pfam:PF01590, this domain carries an additional tongue-like hairpin loop between the fifth beta-sheet and the sixth alpha-helix which functions to seal the chromophore pocket and stabilise the photoactivated far-red-absorbing state (Pfr) [1]. The tongue carries a conserved PRxSF motif, from which an arginine finger points into the chromophore pocket close to ring D forming a salt bridge with a conserved aspartate residue [1]. [1]. 18799745. The structure of a complete phytochrome sensory module in the Pr ground state. Essen LO, Mailliet J, Hughes J;. Proc Natl Acad Sci U S A. 2008;105:14709-14714. (from Pfam)

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2024-10-16

Dimerisation and phospho-acceptor domain of histidine kinases. [1]. 9989504. Structure of CheA, a signal-transducing histidine kinase. Bilwes AM, Alex LA, Crane BR, Simon MI;. Cell 1999;96:131-141. [2]. 18361456. Crystal structure of a novel non-Pfam protein AF1514 from Archeoglobus fulgidus DSM 4304 solved by S-SAD using a Cr X-ray source. Li Y, Bahti P, Shaw N, Song G, Chen S, Zhang X, Zhang M, Cheng C, Yin J, Zhu JY, Zhang H, Che D, Xu H, Abbas A, Wang BC, Liu ZJ;. Proteins 2008;71:2109-13. (from Pfam)

Date:

2024-10-16

This domain receives the signal from the sensor partner in bacterial two-component systems. It is usually found N-terminal to a DNA binding effector domain. [1]. 7699720. Response regulators of bacterial signal transduction systems: selective domain shuffling during evolution. Pao GM, Saier MH;. J Mol Evol 1995;40:136-154. (from Pfam)

Date:

2024-10-16