Parra-Diaz D, Wei Q, Lee E Y, Echegoyen L, Puett D
Department of Chemistry, University of Miami, FL 33124, USA.
FEBS Lett. 1995 Nov 27;376(1-2):58-60. doi: 10.1016/0014-5793(95)01245-2.
X-band electron spin resonance spectroscopy was used to study the binding of vanadium (IV), or vanadyl, to the brain serine/threonine phosphatase-2B, calcineurin. Spectra were determined on frozen solutions of vanadyl and calcineurin at pH 7.4 in the presence of 20% (v/v) glycerol. The binding of vanadyl to the enzyme was established, and the data suggested the presence of two classes of sites, the higher affinity class of which contained two binding sites for vanadyl. The calcium-binding B subunit of the heterodimeric protein was also shown to bind vanadyl. The holoprotein appeared to be stabilized by vanadyl, and vanadyl enhanced enzymatic activity when assayed with or without calmodulin in the absence of calcium.
采用X波段电子自旋共振光谱法研究了钒（IV）或氧钒根与脑丝氨酸/苏氨酸磷酸酶2B（钙调神经磷酸酶）的结合。在pH 7.4、含有20%（v/v）甘油的条件下，对氧钒根和钙调神经磷酸酶的冷冻溶液测定光谱。确定了氧钒根与该酶的结合，数据表明存在两类位点，其中高亲和力类包含两个氧钒根结合位点。还表明异二聚体蛋白的钙结合B亚基也能结合氧钒根。全蛋白似乎因氧钒根而稳定，并且在无钙条件下，无论有无钙调蛋白进行测定时，氧钒根都能增强酶活性。
