Suspected utility of enzymes with multiple activities in the small genome Mycoplasma species: the replacement of the missing "household" nucleoside diphosphate kinase gene and activity by glycolytic kinases.
The small genome Mollicutes whose DNAs are completely sequenced (Mycoplasma genitalium, Mycoplasma pneumoniae, Mycoplasma pulmonis, and Ureaplasma urealyticum [parvum]) lack a gene (ndk) for the presumably essential nucleoside diphosphate kinase (NDPK). We hypothesized that other activities might replace NDPK activity. We found in M. genitalium G37(T), Mycoplasma pneumoniae FH(T), Mycoplasma fermentans PG18(T), and Mycoplasma capricolum subsp. capricolum Kid(T) that their 6-phosphofructokinases (6-PFKs), phosphoglycerate kinases (PGKs), pyruvate kinases (PKs), and acetate kinases (AKs), besides reactant ADP/ATP, could use other ribo- and deoxyribo-purine and pyrimidine NDPs and NTPs. These activities could compensate for the absence of an orthologous ndk gene in the Mycoplasmataceae. They suggest a metabolically varied and consequential role for unrelated and perhaps unsuspected "replacement" or compensatory enzymes that may confound metabolic prediction. We partially purified and biochemically characterized the PKs, 6-PFKs, PGKs, and AKs from M. capricolum subsp. capricolum Kid(T) and M. fermentans PG18(T).
Pollack
J Dennis
JD
Department of Molecular Virology, Immunology, and Medical Genetics, The College of Medicine and Public Health, The Ohio State University, Columbus, Ohio 43210, USA. pollack.1@osu.edu
Myers
Melissa A
MA
Dandekar
Thomas
T
Herrmann
Richard
R
D000084:Acetate Kinase / Q000378:metabolism; D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D002474:Cell-Free System; D002855:Chromatography, Thin Layer; D004591:Electrophoresis, Polyacrylamide Gel; D006019:Glycolysis; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009174:Mycoplasma / Q000201:enzymology* / Q000235:genetics*; D009701:Nucleoside-Diphosphate Kinase / Q000235:genetics* / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D010732:Phosphofructokinase-1 / Q000378:metabolism; D010735:Phosphoglycerate Kinase / Q000378:metabolism; D020033:Protein Isoforms; D011770:Pyruvate Kinase / Q000378:metabolism; D016622:Silver Staining; D013053:Spectrophotometry
D020033:Protein Isoforms; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D010732:Phosphofructokinase-1; D011770:Pyruvate Kinase; D000084:Acetate Kinase; D010735:Phosphoglycerate Kinase; D009701:Nucleoside-Diphosphate Kinase; D010100:Oxygen