Kobayashi Shinya, Fujii Sotaro, Koga Aya, Wakai Satoshi, Matubayasi Nobuyuki, Sambongi Yoshihiro
a Graduate School of Biosphere Science , Hiroshima University , Higashi-Hiroshima , Japan.
b Graduate School of Science Technology and Innovation , Kobe University , Kobe , Japan.
Biosci Biotechnol Biochem. 2017 Jul;81(7):1274-1278. doi: 10.1080/09168451.2017.1303361. Epub 2017 Mar 20.
Reversible denaturation of Pseudomonas aeruginosa cytochrome c (PAc) could be followed using five systematic urea derivatives that differ in the alkyl chain length, i.e. urea, N-methylurea (MU), N-ethylurea (EU), N-propylurea (PU), and N-butylurea (BU). The BU concentration was the lowest required for the PAc denaturation, those of PU, EU, MU, and urea being gradually higher. Furthermore, the accessible surface area difference upon PAc denaturation caused by BU was found to be the highest, those by PU, EU, MU, and urea being gradually lower. These findings indicate that urea derivatives with longer alkyl chains are stronger denaturants. In this study, as many as five systematic urea derivatives could be applied for the reversible denaturation of a single protein, PAc, for the first time, and the effects of the alkyl chain length on protein denaturation were systematically verified by means of thermodynamic parameters.
使用五种烷基链长度不同的系统性尿素衍生物，即尿素、N-甲基尿素（MU）、N-乙基尿素（EU）、N-丙基尿素（PU）和N-丁基尿素（BU），可以追踪铜绿假单胞菌细胞色素c（PAc）的可逆变性。使PAc变性所需的BU浓度最低，PU、EU、MU和尿素的浓度逐渐升高。此外，发现由BU引起的PAc变性时可及表面积差异最大，由PU、EU、MU和尿素引起的差异逐渐降低。这些发现表明，具有较长烷基链的尿素衍生物是更强的变性剂。在本研究中，多达五种系统性尿素衍生物首次可用于单一蛋白质PAc的可逆变性，并且通过热力学参数系统地验证了烷基链长度对蛋白质变性的影响。
