title: Crystal structure of the stomatin operon partner protein from Pyrococcus horikoshii indicates the formation of a multimeric assembly.
abstract: Stomatin, prohibitin, flotillin, and HflK/C (SPFH) domain proteins are found in the lipid raft microdomains of various cellular membranes. Stomatin/STOPP (stomatin operon partner protein) gene pairs are present in both archaeal and bacterial species, and their protein products may be involved in the quality control of membrane proteins. In the present study, the crystal structure of the C-terminal soluble domain of STOPP PH1510 (1510-C) from the hyperthermophilic archaeon Pyrococcus horikoshii was determined at 2.4 Å resolution. The structure of 1510-C had a compact five-stranded β-barrel fold known as an oligosaccharide/oligonucleotide-binding fold (OB-fold). According to crystal packing, 1510-C could assemble into multimers based on a dimer as a basic unit. 1510-C also formed a large cylinder-like structure composed of 24 subunits or a large triangular prism-like structure composed of 12 subunits. These results indicate that 1510-C functions as a scaffold protein to form the multimeric assembly of STOPP and stomatin.
authors.affiliation: School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Hideshi
authors.initials: H
authors.lastname: Yokoyama
authors.affiliation: Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan.
authors.forename: Ikuo
authors.initials: I
authors.lastname: Matsui
keywords: 1510-C, residues 371–441 of PH1510; 1510-N, residues 16–236 of PH1510; 471-C, residues 72–143 of PH0471; Crystal structure; OB-fold; OB-fold, oligosaccharide/oligonucleotide-binding fold; Pyrococcus horikoshii; SPFH; STOPP, stomatin operon partner protein; Stomatin operon partner protein; r.m.s.d., root-mean-square deviation