Yoshihara S, Tatsumi K
Arch Biochem Biophys. 1985 Oct;242(1):213-24. doi: 10.1016/0003-9861(85)90495-3.
Guinea pig aldehyde oxidase was purified about 120-fold at a yield of 26% from liver cytosol by sequential column chromatography using DEAE-cellulose, FMN-Sepharose 4B, and Sephacryl S-300. The purified enzyme showed many similarities with the rabbit liver aldehyde oxidase reported by other workers with respect to its absolute spectra, molecular weight, and cofactor compositions of molybdenum, FAD, and nonheme iron. This enzyme efficiently utilized 2-hydroxypyrimidine and benzaldehyde as electron donors while N1-methylnicotinamide was 40 times less effective than 2-hydroxypyrimidine. Diphenyl sulfoxide was reduced anaerobically to diphenyl sulfide in the presence of electron donors. This activity was highly susceptible to SKF 525-A as well as the known inhibitors for aldehyde oxidase such as menadione, estradiol, and potassium cyanide. This enzyme also reduced dibenzyl sulfoxide, phenothiazine sulfoxide, D-biotin methyl ester d-sulfoxide, and quinoline N-oxide, but not L-methionine sulfoxide, dimethyl sulfoxide, D-biotin methyl ester l-sulfoxide, and D-biotin d- and l-sulfoxides, as well as diphenyl sulfone. These results indicate that aldehyde oxidase in guinea pig liver functions as a sulfoxide reductase with selective substrate specificity under anaerobic conditions.
通过使用DEAE - 纤维素、FMN - 琼脂糖凝胶4B和Sephacryl S - 300进行连续柱色谱法，从豚鼠肝细胞溶胶中纯化出醛氧化酶，纯化倍数约为120倍，产率为26%。纯化后的酶在绝对光谱、分子量以及钼、黄素腺嘌呤二核苷酸（FAD）和非血红素铁的辅因子组成方面，与其他研究者报道的兔肝醛氧化酶有许多相似之处。该酶能有效地利用2 - 羟基嘧啶和苯甲醛作为电子供体，而N1 - 甲基烟酰胺的效果比2 - 羟基嘧啶低40倍。在电子供体存在的情况下，二苯基亚砜在厌氧条件下被还原为二苯硫醚。这种活性对SKF 525 - A以及醛氧化酶的已知抑制剂如甲萘醌、雌二醇和氰化钾高度敏感。该酶还能还原二苄基亚砜、吩噻嗪亚砜、D - 生物素甲酯d - 亚砜和喹啉N - 氧化物，但不能还原L - 甲硫氨酸亚砜、二甲基亚砜、D - 生物素甲酯l - 亚砜以及D - 生物素d - 和l - 亚砜，还有二苯砜。这些结果表明，豚鼠肝脏中的醛氧化酶在厌氧条件下作为一种具有选择性底物特异性的亚砜还原酶发挥作用。
