地衣芽孢杆菌植酸酶基因的克隆及其在大肠杆菌中的表达

根据已发表的Bacillus licheniformis植酸酶基因DNA序列(13eneBank AF469936)，设计并合成了一对引物，应用PCR技术，以地衣芽孢杆菌AB91062的总DNA为模板，扩增出了植酸酶基因phyL的编码区，并将其克隆到pMD18-T载体上，进行了序列测定，测序结果经Genetool序列分析表明该基因编码区长1146bp，编码381个氨基酸，与已发表的Bacillus lichenjformis植酸酶基因序列在核苷酸水平上与所发表的序列有92％的同源性；在氨基酸水平上与已发表的衣芽孢杆菌植酸酶相似性为93％．并将该基因编码区克隆到大肠杆菌表达质粒pHBM625上，并在大肠杆菌中实现了高效表达，表达产物具有正常的生物学活性．

Cloning of phytase gene from Bacillus licheniformis and its expression in Escherichia coli

According to the published phytase gene sequence from Bacillus licheniformis,primers were designed to amplify phytase gene by PCR.The PCR product was cloned to pMD18-T and sequenced.The phytase gene we cloned comprises 1?146 nucleotides and encodes a polypeptide of 381 amino acids.Compared with published phyL gene sequence,the phytase gene showed 92?% identity on nucleotides level and 93?% identity on amino acids level. It was also cloned to the expression vector pHBM625 and overexpressed in E.coli.The expressed product has normal bioactivity.