Evaluation of the thermal stability of clinically relevant enzymes at 37 degrees C.
The thermal stability at 37 degrees C of several clinically relevant enzymes and isoenzymes was assessed by measuring changes in enzyme activity as a function of time under incubation and reaction conditions. Selwyn plots were used in the reaction-condition assessments. Except for CK-1 (BB), all the enzymes investigated are stable enough at 37 degrees C to permit assay. These enzymes were LDH-1, LDH-5, s-AspAT, m-AspAT, apo-s-AspAT, apo-m-AspAT, ALP-liver, ALP-bone, ALP-intestine, ALT, apo-ALT, CK-2, and CK-3. CK-1 is stable at 37 degrees C under assay conditions but not under incubation conditions. We specifically avoided using Arrhenius plots to evaluate thermal stability and point out pitfalls inherent in their indiscriminate use.
D000410:Alanine Transaminase / Q000378:metabolism; D001051:Apoenzymes / Q000378:metabolism; D001219:Aspartate Aminotransferases / Q000378:metabolism; D003402:Creatine Kinase / Q000378:metabolism; D004798:Enzymes / Q000032:analysis*; D006801:Humans; D007527:Isoenzymes / Q000032:analysis; D007700:Kinetics; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D011487:Protein Conformation; D011489:Protein Denaturation; D012996:Solutions; D013696:Temperature
D001051:Apoenzymes; D004798:Enzymes; D007527:Isoenzymes; D012996:Solutions; D007770:L-Lactate Dehydrogenase; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D003402:Creatine Kinase