Porcelli M, Cacciapuoti G, Fusco S, Massa R, d'Ambrosio G, Bertoldo C, De Rosa M, Zappia V
Facoltà di Medicina e Chirurgia, Seconda Universita di Napoli, Naples,Italy.
FEBS Lett. 1997 Feb 3;402(2-3):102-6. doi: 10.1016/s0014-5793(96)01505-0.
Two thermophilic and thermostable enzymes, isolated from Sulfolobus solfataricus, S-adenosylhomocysteine hydrolase and 5'-methylthioadenosine phosphorylase, were exposed to 10.4 GHz microwave radiation in order to discriminate between thermal and non-thermal microwave effects. The exposure causes a non-thermal, irreversible and time-dependent inactivation of both enzymes; the inactivation rate is related to the energy absorbed and is independent of the enzyme concentration. The influence of salts on enzyme inactivation has also been investigated. Conformational changes of S-adenosylhomocysteine hydrolase, detected by fluorescence and circular dichroism techniques, suggest that microwaves induce protein structural rearrangements not related to temperature.
从嗜热栖热菌中分离出的两种嗜热且耐热的酶，即S-腺苷同型半胱氨酸水解酶和5'-甲硫基腺苷磷酸化酶，被置于10.4 GHz微波辐射下，以区分热效应和非热微波效应。这种照射会导致这两种酶发生非热、不可逆且随时间变化的失活；失活速率与吸收的能量有关，且与酶浓度无关。同时也研究了盐对酶失活的影响。通过荧光和圆二色性技术检测到的S-腺苷同型半胱氨酸水解酶的构象变化表明，微波会诱导与温度无关的蛋白质结构重排。
