title: A direct continuous pH-spectrophotometric assay for arginine kinase activity.
abstract: A direct and continuous spectrophotometric method was developed for determining arginine kinase (phosphoarginine synthesis) activity. Protons are produced during the phosphoarginine synthesis course, so adding the complex acid-base indicator to this solution and monitoring the decrease of absorbance of the solution at 575 nm will follow the arginine kinase activity. For this condition, one activity unit of arginine kinase was defined as 1 micromol H+ produced in 1 minute in the enzymatic reaction catalyzed by arginine kinase.
authors.affiliation: Department of Biological Science and Biotechnology, Tsinghua University, Beijing 100084, P R China.
authors.forename: Z
authors.initials: Z
authors.lastname: Yu
authors.forename: J
authors.initials: J
authors.lastname: Pan
authors.forename: H M
authors.initials: HM
authors.lastname: Zhou
mesh_terms: D001122:Arginine Kinase / Q000032:analysis*; D001681:Biological Assay; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010637:Phenolsulfonphthalein / Q000031:analogs & derivatives* / Q000378:metabolism; D013053:Spectrophotometry / Q000379:methods; D013944:Thymolphthalein / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: C009743:Cresol red; C013713:thymol blue; D001122:Arginine Kinase; D010637:Phenolsulfonphthalein; D013944:Thymolphthalein