Characterization of recombinant PPi-dependent 6-phosphofructokinases from Methylosinus trichosporium OB3b and Methylobacterium nodulans ORS 2060.
The properties of the purified recombinant PPi-dependent 6-phosphofructokinases (PPi-PFKs) from the methanotroph Methylosinus trichosporium OB3b and rhizospheric phytosymbiont Methylobacterium nodulans ORS 2060 were determined. The dependence of activities of PPi-PFK-His(6)-tag from Ms. trichosporium OB3b (6 × 45 kDa) and PPi-PFK from Mb. nodulans ORS 2060 (4 × 43 kDa) on the concentrations of substrates of forward and reverse reactions conformed to Michaelis-Menten kinetics. Besides fructose-6-phosphate, the enzymes also phosphorylated sedoheptulose-7-phosphate. ADP or AMP (1 mM each) inhibited activity of the Ms. trichosporium PPi-PFK but did not affect the activity of the Mb. nodulans enzyme. Preference of PPi-PFKs to fructose-1,6-bisphosphate implied a predominant function of the enzymes in hexose phosphate synthesis in these bacteria. PPi-PFKs from the methylotrophs have low similarity of translated amino acid sequences (17% identity) and belong to different phylogenetic subgroups of type II 6-phosphofructokinases. The relationship of PPi-PFKs with microaerophilic character of Ms. trichosporium OB3b and adaptation of Mb. nodulans ORS 2060 to anaerobic phase of phytosymbiosis are discussed.
Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
O N
ON
Rozova
V N
VN
Khmelenina
Y A
YA
Trotsenko
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000378:metabolism; D005636:Fructosephosphates / Q000378:metabolism; D007700:Kinetics; D020580:Methylobacterium / Q000737:chemistry / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D020602:Methylosinus trichosporium / Q000737:chemistry / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D010732:Phosphofructokinase-1 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D004791:Enzyme Inhibitors; D005636:Fructosephosphates; D011994:Recombinant Proteins; C027618:fructose-6-phosphate; D010732:Phosphofructokinase-1