Glucosylglycerate biosynthesis in the deepest lineage of the Bacteria: characterization of the thermophilic proteins GpgS and GpgP from Persephonella marina.
The pathway for the synthesis of glucosylglycerate (GG) in the thermophilic bacterium Persephonella marina is proposed based on the activities of recombinant glucosyl-3-phosphoglycerate (GPG) synthase (GpgS) and glucosyl-3-phosphoglycerate phosphatase (GpgP). The sequences of gpgS and gpgP from the cold-adapted bacterium Methanococcoides burtonii were used to identify the homologues in the genome of P. marina, which were separately cloned and overexpressed as His-tagged proteins in Escherichia coli. The recombinant GpgS protein of P. marina, unlike the homologue from M. burtonii, which was specific for GDP-glucose, catalyzed the synthesis of GPG from UDP-glucose, GDP-glucose, ADP-glucose, and TDP-glucose (in order of decreasing efficiency) and from d-3-phosphoglycerate, with maximal activity at 90 degrees C. The recombinant GpgP protein, like the M. burtonii homologue, dephosphorylated GPG and mannosyl-3-phosphoglycerate (MPG) to GG and mannosylglycerate, respectively, yet at high temperatures the hydrolysis of GPG was more efficient than that of MPG. Gel filtration indicates that GpgS is a dimeric protein, while GpgP is monomeric. This is the first characterization of genes and enzymes for the synthesis of GG in a thermophile.
Costa
Joana
J
Departamento de Bioquímica, Universidade de Coimbra, 3001-401 Coimbra, Portugal.
Empadinhas
Nuno
N
da Costa
Milton S
MS
D001419:Bacteria / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D002384:Catalysis; D005960:Glucosides / Q000096:biosynthesis*; D005988:Glyceric Acids / Q000378:metabolism*; D006156:Guanosine Diphosphate Sugars / Q000378:metabolism*; D008969:Molecular Sequence Data; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000502:physiology; D010802:Phylogeny
D001426:Bacterial Proteins; D005960:Glucosides; D005988:Glyceric Acids; D006156:Guanosine Diphosphate Sugars; C100085:guanosine diphosphate glucose; C005156:3-phosphoglycerate; D017853:Phosphotransferases (Alcohol Group Acceptor); C441640:mannosyl-3-phosphoglycerate phosphatase; D010744:Phosphoric Monoester Hydrolases; C022364:phosphoglycerate phosphatase