title: Purification and characterization of a novel thermostable extracellular protein tyrosine phosphatase from Metarhizium anisopliae strain CQMa102.
abstract: An extracellular phosphatase was purified to homogeneity from the entomopathogenic fungus Metarhizium anisopliae with a 41.0% yield. The molecular mass and isoelectric point of the purified enzyme were about 82.5 kDa and 9.5 respectively. The optimum pH and temperature were about 5.5 and 75 degrees C when using O-phospho-L-tyrosine as substrate. The protein displayed high stability in a pH range 3.0-9.5 at 30 degrees C and was remarkably thermostable at 70 degrees C. The purified enzyme showed high activity on O-phospho-L-tyrosine and protein tyrosine phosphatase substrate monophosphate (a specific substrate of protein tyrosine phosphatase). Although one peptide of the phosphatase shared identity with one alkaline phosphatase of Neurospora crassa, its substrate specificity and inhibitor sensitivity indicate that the enzyme is a protein tyrosine phosphatase.
authors.affiliation: Genetic Engineering Research Center, Bioengineering College, Chongqing University, R. P. China.
authors.forename: Zhenlun
authors.initials: Z
authors.lastname: Li
authors.forename: Zhongkang
authors.initials: Z
authors.lastname: Wang
authors.forename: Guoxiong
authors.initials: G
authors.lastname: Peng
authors.forename: Youping
authors.initials: Y
authors.lastname: Yin
authors.forename: Hua
authors.initials: H
authors.lastname: Zhao
authors.forename: Yueqing
authors.initials: Y
authors.lastname: Cao
authors.forename: Yuxian
authors.initials: Y
authors.lastname: Xia
mesh_terms: D002412:Cations / Q000737:chemistry / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology; D006031:Glycosylation; D006863:Hydrogen-Ion Concentration; D006999:Hypocreales / Q000166:cytology / Q000201:enzymology* / Q000254:growth & development; D007700:Kinetics; D008670:Metals / Q000737:chemistry / Q000494:pharmacology; D008970:Molecular Weight; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000302:isolation & purification*; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D002412:Cations; D004791:Enzyme Inhibitors; D008670:Metals; D017027:Protein Tyrosine Phosphatases