Amani Mojtaba, Moosavi-Movahedi Ali A, Floris Giovanni, Mura Anna, Kurganov Boris I, Ahmad Faizan, Saboury Ali A
Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
Biophys Chem. 2007 Feb;125(2-3):254-9. doi: 10.1016/j.bpc.2006.08.006. Epub 2006 Aug 23.
Thermal denaturation of Euphorbia latex amine oxidase (ELAO) has been studied by enzymatic activity, circular dichroism and differential scanning calorimetry. Thermal denaturation of ELAO is shown to be an irreversible process. Checking the validity of two-state it really describes satisfactorily the thermal denaturation of ELAO. Based on this model we obtain the activation energy, parameter T(*) (the absolute temperature at which the rate constant of denaturation is equal to 1 min(-1)), and total enthalpy of ELAO denaturation. HPLC experiments show that the thermal denatured enzyme conserves its dimeric state. The N(2)-->kD(2) model for thermal denaturation of ELAO is proposed: where N(2) and D(2) are the native and denatured dimer, respectively.
通过酶活性、圆二色性和差示扫描量热法研究了大戟乳胶胺氧化酶（ELAO）的热变性。结果表明，ELAO的热变性是一个不可逆过程。检验两态模型的有效性，结果表明它确实能很好地描述ELAO的热变性。基于该模型，我们得到了活化能、参数T*（变性速率常数等于1 min⁻¹时的绝对温度）以及ELAO变性的总焓。高效液相色谱实验表明，热变性酶保留其二聚体状态。提出了ELAO热变性的N₂→kD₂模型：其中N₂和D₂分别为天然二聚体和变性二聚体。
