金针菇产植酸酶菌株的筛选及植酸酶基因区域的克隆

The Screening of Flammulina velutipes Strain Producing Phytase and Cloning of Its Phytase Gene Region

从金针菇(Flammulina velutipes)7个菌株中筛选出1株高产植酸酶菌株。根据GenBank中植酸酶基因的保守区设计并合成一对特异性引物,以金针菇菌丝的总DNA为模板,通过PCR扩增,获得了一条长约790bp的片段。DNA序列测定结果表明,该片段长度为788bp,采用Blast软件进行序列比对发现,该片段与平田头菇(Agrocybe pediades)的植酸酶基因phy(GenBankAccession:CAC48160)编码的氨基酸具有64%的序列同源性。该片段含有2个内含子,含有植酸酶基因的活性位点高度保守序列(Active-site sequence)-RHGXRXPT[1]。

One Flammulina velutipes strain producing high yield of phytase was screened from seven Flammulina velutipes strains. The phytase gene region was cloned by PCR amplification from Flammulina velutipes genomic DNA with a pair of specific primers designed according to the conserved sequence of phytase genes in the GenBank. DNA sequencing determination results showed that the fragment length was 788bp. Sequence analysis with Blast software indicated that the deduced amino acid sequence was 64% of homology with the amino acid sequence of phytase gene phy （GenBank Accession： CACA8160） from Agrocybe pediades. The fragment contained two introns and the active-site high-degree conserved sequence of phytase genes - RHGXRXPT.