title: Optimal analytical conditions for catalase in fresh water prawn, Macrobrachium malcolmsonii.
abstract: The cytosol of hepatopancreas was prepared from the freshwater prawn Macrobrachium malcolmsonii, and optimal assay conditions, ie., concentration of substrate, pH, and temperature, were determined to measure basal activities and kinetic constants of catalase activity. The properties of catalase were examined in M. macolmsonii, because quantitative data on catalase are limited in crustacean species. The optimal pH for catalase was 7.0. The activation energy was 3.55 Kcal/mol and energy inhibition value was 5.16 Kcal/mol. The value of energy inhibition is higher than that of energy activation. This may be due to inhibition of catalase by some substrate other than H2O2. A Km of 66.6 mM was also determined from various concentrations of substrate.
authors.affiliation: Department of Animal Science, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India. sarun@rediffmail.com
authors.forename: S
authors.initials: S
authors.lastname: Arun
authors.forename: R
authors.initials: R
authors.lastname: Thirumurugan
authors.forename: R
authors.initials: R
authors.lastname: Visakan
authors.forename: S
authors.initials: S
authors.lastname: Balamurugan
authors.forename: V
authors.initials: V
authors.lastname: Arunachalam
authors.forename: P
authors.initials: P
authors.lastname: Subramanian
mesh_terms: D000818:Animals; D002374:Catalase / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000737:chemistry*; D002458:Cell Fractionation / Q000379:methods*; D004735:Energy Transfer; D004789:Enzyme Activation; D004791:Enzyme Inhibitors; D005618:Fresh Water; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D033541:Palaemonidae / Q000737:chemistry* / Q000145:classification / Q000201:enzymology*; D013045:Species Specificity; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D004791:Enzyme Inhibitors; D002374:Catalase