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从土壤中筛选到产植酸酶的黑曲霉菌株Ａｓｐｅｒｇｉｌｌｕｓｎｉｇｅｒ９６３，对其所产植酸酶的生理生化性质研究表明其具有适合于在饲料中使用的优良性质。它的酶活性最适温度为５５℃，最适ｐＨ值分别为ｐＨ１．８和５．７，并且在ｐＨ１．８－５．７的范围内，植酸酶均能维持较高的酶活性。摇瓶发酵实验表明，植酸酶的表达量为１６５Ｕ／ｍＬ发酵液。通过ＰＣＲ的方法克隆了植酸酶基因扯ｐｈｙＡ２，ＤＮＡ全序列分析表明其结构基因全长１５０６个核苷酸（编码４６７个氨基酸），５’端有一编码１９个氨基酸的信号肽序列，其中包含一段长１０２个核苷酸的内含子。此序列与曾报道的源于Ａｓｐｅｒｇｉｌｌｕｓｎｉｇｅｒｖａｒ．ａｗａｍｏｒｉ的植酸酶基因ｐｈｙＡ有一定的差异，其ＤＮＡ序列同源性为９１．８％，所编码的蛋日同源性为９１．６％，相应的酶学性质也有所不同。
Aspergillus niger963, a phytase-producing Aspergillus niger963 strain, was screened from the soil and the physiological and biochemical properties of the phytase-producing Aspergillus niger963were demonstrated to be of good quality for use in feedstuffs. The optimum temperature of enzyme activity was 55 ℃, the optimal pH value was pH1.8 and 5.7 respectively, and the phytase could maintain higher enzyme activity in the range of pH1.8-5.7. Flask fermentation experiments showed that the expression of phytase 165U / mL fermentation broth. Phytase gene PhyA2 was cloned by PCR. The full-length DNA sequence analysis showed that its structural gene was 1506 nucleotides in length (encoding 467 amino acids) and a signal peptide sequence encoding 19 amino acids at the 5 ’end, which contained A 102-nucleotide intron. This sequence is similar to that reported from Aspergillus nigervar. The phyA phyA gene phyA of awamori had some differences. The homology of its DNA sequence was 91.8%, the encoded homology was 91.6%, and the corresponding enzymatic properties were also different.