2024-03-28T18:57:32Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/145002022-11-17T02:08:08Zhdl_2115_20039hdl_2115_116Structural analysis of the transcriptional regulator homolog protein from Pyrococcus horikoshii OT3Okada, UiSakai, NaokiYao, MinWatanabe, NobuhisaTanaka, Isao464.2PH1061 is a hypothetical protein of 100 residues (11.4 kDa) from the hyperthermophilic archaebacterium, Pyrococcus horikoshii OT31, and is conserved among many archaeal and bacterial organisms. Although the functions in these organisms are still unknown, a Pfam2 database search revealed that PH1061 has a helix-turn-helix (HTH) motif (“HTH_5 motif” in the Pfam database), and suggested that it is a DNA-binding protein, like members of the ArsR family3. ArsR is a transcriptional repressor of the arsenic resistance operon in Escherichia coli and other members of this family involve zinc-sensing transcriptional repressors, such as CzrA4 from Staphylococcus aureus and SmtB5 from Synechococcus pcc7942. The primary sequence similarities to PH1061 are 20%, 21%, and 6.6% with ArsR, CzrA, and SmtB, respectively. There are 10 proteins with the HTH_5 motif in P. horikoshii, but none of their functions are known. For structure-based functional analysis, the three-dimensional structure of PH1061 was determined at a resolution of 2.05 Å using the multi-wavelength anomalous diffraction (MAD) method.Wiley-LissJournal Articleapplication/pdfhttp://hdl.handle.net/2115/14500https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/14500/1/manuscript.pdf0887-35851097-0134Proteins: Structure Function and Bioinformatics634108410862006-06enginfo:pmid/16506234info:doi/10.1002/prot.20913Copyright (c) 2006 Wiley-Liss, Inc.author