RRC ID 21521
著者 Chiba Y, Oshima K, Arai H, Ishii M, Igarashi Y.
タイトル Discovery and analysis of cofactor-dependent phosphoglycerate mutase homologs as novel phosphoserine phosphatases in Hydrogenobacter thermophilus.
ジャーナル J Biol Chem
Abstract Phosphoserine phosphatase (PSP) catalyzes the dephosphorylation of phosphoserine to serine and inorganic phosphate. PSPs, which have been found in all three domains of life, belong to the haloacid dehalogenase-like hydrolase superfamily. However, certain organisms, particularly bacteria, lack a classical PSP gene, although they appear to possess a functional phosphoserine synthetic pathway. The apparent lack of a PSP ortholog in Hydrogenobacter thermophilus, an obligately chemolithoautotrophic and thermophilic bacterium, represented a missing link in serine anabolism because our previous study suggested that serine should be synthesized from phosphoserine. Here, we detected PSP activity in cell-free extracts of H. thermophilus and purified two proteins with PSP activity. Surprisingly, these proteins belonged to the histidine phosphatase superfamily and had been annotated as cofactor-dependent phosphoglycerate mutase (dPGM). However, because they possessed neither mutase activity nor the residues important for the activity, we defined these proteins as novel-type PSPs. Considering the strict substrate specificity toward l-phosphoserine, kinetic parameters, and PSP activity levels in cell-free extracts, these proteins were strongly suggested to function as PSPs in vivo. We also detected PSP activity from "dPGM-like" proteins of Thermus thermophilus and Arabidopsis thaliana, suggesting that PSP activity catalyzed by dPGM-like proteins may be distributed among a broad range of organisms. In fact, a number of bacterial genera, including Firmicutes and Cyanobacteria, were proposed to be strong candidates for possessing this novel type of PSP. These findings will help to identify the missing link in serine anabolism.
巻・号 287(15)
ページ 11934-41
公開日 2012-4-6
DOI 10.1074/jbc.M111.330621
PII S0021-9258(20)53119-0
PMID 22337887
PMC PMC3320941
MeSH Amino Acid Sequence Bacteria, Aerobic / enzymology* Bacterial Proteins / chemistry Bacterial Proteins / isolation & purification Bacterial Proteins / metabolism* Chromatography, Liquid Coenzymes / metabolism* Enzyme Assays Kinetics Molecular Weight Phosphoglycerate Mutase / genetics* Phosphoric Monoester Hydrolases / chemistry Phosphoric Monoester Hydrolases / isolation & purification Phosphoric Monoester Hydrolases / metabolism* Phylogeny Protein Subunits Recombinant Proteins / chemistry Recombinant Proteins / isolation & purification Recombinant Proteins / metabolism Sequence Analysis, Protein Sequence Homology, Amino Acid Substrate Specificity
IF 4.238
引用数 18
WOS 分野 BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
シロイヌナズナ / 植物培養細胞・遺伝子 pda20245 pdz61570
遺伝子材料 Thermus thermophilus expression plasmid TEx14G12 (THR005756)