title: Studies on the stability of creatine kinase isozymes.
abstract: Research on the stabilizing properties of creatine kinase isozymes CK-BB, CK-MB, and CK-MM showed that minor alteration of their sequence and structure influenced their stability significantly. An analysis of the stability of the isozymes in storage after freeze drying indicates that creatine kinase isozymes are all in monomer form because of the loss of subunit interactions. Freeze-drying leads to the oxidization of CK-BB and rearrangement of CK-MB. There are also differences in the unfolding of the isozymes in urea. CK-BB and CK-MB are unfolded in lower urea concentrations than CK-MM. Differences in the thermal unfolding were also examined by differential scanning calorimetry. This paper discusses the potential biological significance of these results.
authors.affiliation: Protein Science Laboratory of the Ministry of Education, Department of Biological Sciences and Biotechnology, School of Life Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Guo
authors.forename: Zheng
authors.initials: Z
authors.lastname: Wang
authors.forename: Xicheng
authors.initials: X
authors.lastname: Wang
mesh_terms: D000818:Animals; D002152:Calorimetry, Differential Scanning / Q000379:methods; D002942:Circular Dichroism; D003402:Creatine Kinase / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D052276:Creatine Kinase, BB Form; D052279:Creatine Kinase, MB Form; D052283:Creatine Kinase, MM Form; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability / Q000187:drug effects; D005612:Freeze Drying / Q000379:methods; D007527:Isoenzymes / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D011487:Protein Conformation / Q000187:drug effects; D011489:Protein Denaturation / Q000187:drug effects; D017510:Protein Folding; D017433:Protein Structure, Secondary / Q000187:drug effects; D013050:Spectrometry, Fluorescence; D014508:Urea / Q000494:pharmacology
chemical_list: D007527:Isoenzymes; D014508:Urea; D003402:Creatine Kinase; D052276:Creatine Kinase, BB Form; D052279:Creatine Kinase, MB Form; D052283:Creatine Kinase, MM Form