title: Studies on the role of HtpG in the tetrapyrrole biosynthesis pathway of the cyanobacterium Synechococcus elongatus PCC 7942.
abstract: In cyanobacterium Synechococcus elongatus PCC 7942, we observed that htpG-overexpression caused remarkable growth inhibition. In addition, subcellular fractionation experiments showed that HtpG was localized in the membrane fraction. To understand its function in cyanobacteria, we carried out yeast two-hybrid screening to identify specific proteins interacting with HtpG, and found out, HemE, uroporphyrinogen decarboxylase. When compared to the wild-type strain, the htpG-null mutant and -overexpressing strains exhibited higher and lower cytosolic HemE activity, based on the coproporphyrin production, respectively. These results strongly suggest that HtpG is involved in the regulation of tetrapyrrole biosynthesis through interacting with HemE protein.
authors.affiliation: Department of Bioscience, Tokyo University of Agriculture, Sakuragaoka 1-1-1, Setagaya-ku, Tokyo 156-8502, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Watanabe
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Masakazu
authors.initials: M
authors.lastname: Saito
authors.forename: Masumi
authors.initials: M
authors.lastname: Sato
authors.forename: Kaori
authors.initials: K
authors.lastname: Nimura-Matsune
authors.forename: Taku
authors.initials: T
authors.lastname: Chibazakura
authors.forename: Shigeru
authors.initials: S
authors.lastname: Taketani
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Nakamoto
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Yoshikawa
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D049109:Cell Proliferation; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation / Q000235:genetics; D011485:Protein Binding; D046940:Synechococcus / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D045725:Tetrapyrroles / Q000096:biosynthesis*; D014575:Uroporphyrinogen Decarboxylase / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D018841:HSP90 Heat-Shock Proteins; D045725:Tetrapyrroles; C066720:HtpG protein, bacteria; D014575:Uroporphyrinogen Decarboxylase