Gene Cloning, Expression, and Characterization of a Novel Phytase from Dickeya paradisiaca

作者：Gu Weina; Huang Huoqing; Meng Kun; Yang Peilong; Fu Dawei; Luo Huiying; Wang Yaru; Yao Bin^*; Zhan Zhichun

来源：Applied Biochemistry and Biotechnology, 2009, 157(2): 113-123.

DOI：10.1007/s12010-008-8329-6

• Degenerate PCR
• Dickeya paradisiaca
• Histidine acid phosphatase
• Phytase
• TAIL-PCR

A novel phytase gene, appA, was isolated by degenerate polymerase chain reaction (PCR) and thermal asymmetric interlaced PCR from Dickeya paradisiaca. The full-length appA comprises 1278 bp and encodes 425 amino acid residues, including a 23-residue putative N-terminal signal peptide. The deduced amino acid sequence of appA reveals the conserved motifs RHGXRXP and HD, which are typical of histidine acid phosphatases; significantly, APPA shows maximum identity (49%) to a phytase from Klebsiella pneumoniae. To characterize the properties of APPA, appA was expressed in Escherichia coli and purified. The purified recombinant APPA has two pH optima at pH 4.5 and 5.5, optimum temperature at 55 A degrees C, specific activity of 769 U/mg, and good pH stability. The K (m) value for the substrate sodium phytate is 0.399 mM with a V (max) of 666 U/mg. To our knowledge, this is the first report of a phytase or phytase gene isolated from Dickeya.

• 出版日期2009-5
• 单位石家庄学院; 中国农业科学院