title: Crystallographic analysis of a subcomplex of the transsulfursome with tRNA for Cys-tRNA(Cys) synthesis.
abstract: In most organisms, Cys-tRNA(Cys) is directly synthesized by cysteinyl-tRNA synthetase (CysRS). Many methanogenic archaea, however, use a two-step, indirect pathway to synthesize Cys-tRNA(Cys) owing to a lack of CysRS and cysteine-biosynthesis systems. This reaction is catalyzed by O-phosphoseryl-tRNA synthetase (SepRS), Sep-tRNA:Cys-tRNA synthase (SepCysS) and SepRS/SepCysS pathway enhancer (SepCysE) as the transsulfursome, in which SepCysE connects both SepRS and SepCysS. On the transsulfursome, SepRS first ligates an O-phosphoserine to tRNA(Cys), and the mischarged intermediate Sep-tRNA(Cys) is then transferred to SepCysS, where it is further modified to Cys-tRNA(Cys). In this study, a subcomplex of the transsulfursome with tRNA(Cys) (SepCysS-SepCysE-tRNA(Cys)), which is involved in the second reaction step of the indirect pathway, was constructed and then crystallized. The crystals diffracted X-rays to a resolution of 2.6 Å and belonged to space group P6522, with unit-cell parameters a = b = 107.2, c = 551.1 Å. The structure determined by molecular replacement showed that the complex consists of a SepCysS dimer, a SepCysE dimer and one tRNA(Cys) in the asymmetric unit.
authors.affiliation: Graduate School of Life Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan.
authors.forename: Meirong
authors.initials: M
authors.lastname: Chen
authors.affiliation: Graduate School of Life Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan.
authors.forename: Yuto
authors.initials: Y
authors.lastname: Nakazawa
authors.affiliation: Graduate School of Life Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan.
authors.forename: Yume
authors.initials: Y
authors.lastname: Kubo
authors.affiliation: Graduate School of Life Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan.
authors.forename: Nozomi
authors.initials: N
authors.lastname: Asano
authors.affiliation: Graduate School of Life Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Kato
authors.affiliation: Faculty of Advanced Life Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan.
authors.forename: Isao
authors.initials: I
authors.lastname: Tanaka
authors.affiliation: Graduate School of Life Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan.
authors.forename: Min
authors.initials: M
authors.lastname: Yao
mesh_terms: D000595:Amino Acid Sequence; D000604:Amino Acyl-tRNA Synthetases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D019843:Archaeal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D063747:Methanocaldococcus / Q000737:chemistry* / Q000201:enzymology; D010957:Plasmids / Q000737:chemistry / Q000378:metabolism; D012350:RNA, Transfer, Cys / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D014961:X-Ray Diffraction
chemical_list: D019843:Archaeal Proteins; D012350:RNA, Transfer, Cys; D011994:Recombinant Proteins; D000604:Amino Acyl-tRNA Synthetases; C019975:cysteinyl-tRNA synthetase
keywords: Cys-tRNACys; SepCysE; SepCysS; SepRS; transsulfursome