title: Partial purification and properties of a highly specific trehalose phosphate phosphatase from Mycobacterium smegmatis.
abstract: A specific trehalose phosphate phosphatase was purified approximately 50-fold from Mycobacterium smegmatis. The enzyme had a pH optimum of about 7.0 and was stimulated by Mg(2+). The optimum concentration of Mg(2+) was about 1.5 x 10(-3)m. Of other divalent cations tested, only Co(2+) showed some activity. The K(m) for trehalose phosphate was found to be about 1.5 x 10(-3)m. The enzyme showed slight activity toward mannose-6-P and fructose-6-P but was inactive on a large number of other phosphorylated compounds. Citrate was a competitive inhibitor of the enzyme both with respect to trehalose phosphate concentration and Mg(2+) concentration. This inhibition appears to be due to chelation of Mg(2+) by this compound. Ethylenediaminetetraacetic acid and NaF were also inhibitors of the enzyme, but these inhibitions were noncompetitive.
mesh_terms: D002130:Calcium Phosphates; D050260:Carbohydrate Metabolism; D011232:Chemical Precipitation; D002712:Chlorides; D002848:Chromatography, DEAE-Cellulose; D002951:Citrates / Q000494:pharmacology; D003035:Cobalt / Q000494:pharmacology; D004187:Disaccharides / Q000096:biosynthesis; D004492:Edetic Acid / Q000494:pharmacology; D005459:Fluorides / Q000494:pharmacology; D006600:Hexosephosphates / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese; D009161:Mycobacterium / Q000201:enzymology*; D010710:Phosphates / Q000096:biosynthesis; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D000644:Quaternary Ammonium Compounds; D012964:Sodium; D013431:Sulfates; D013997:Time Factors
chemical_list: D002130:Calcium Phosphates; D002712:Chlorides; D002951:Citrates; D004187:Disaccharides; D006600:Hexosephosphates; D010710:Phosphates; D000644:Quaternary Ammonium Compounds; D013431:Sulfates; D003035:Cobalt; D008345:Manganese; D004492:Edetic Acid; D012964:Sodium; D010744:Phosphoric Monoester Hydrolases; D008274:Magnesium; D005459:Fluorides