Molecular cloning and the biochemical characterization of two novel phytases from B. subtilis 168 and B. licheniformis

A. Tye, F. Siu, Yun Chung Leung, B. Lim

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131 Citations (Scopus)


A novel phytase gene (phyL) was cloned from Bacillus licheniformis by multiple steps of degenerate and inverse PCR. The coding region of the phyL gene was 1,146 bp in size and a promoter region of approximately 300 bp was identified at the upstream sequence. This gene, together with a phytase gene (168phyA) identified in the B. subtilis strain 168 genome by a homology search, was cloned and over-expressed in B. subtilis using a φ105MU331 prophage vector system. Up to 35 units of phytase/ml were secreted into the culture media; and mature enzymes of around 44-47 kDa were purified for characterization. Both phytases exhibited broad temperature and pH optima and showed high thermostability. Of the two, the phytase encoded by phyL exhibited higher thermostability, even at a lower calcium concentration, as it was able to recover 80% of its original activity after denaturation at 95°C for 10 min. With their neutral pH optima and good temperature stabilities, these Bacillus phytases are good candidates for animal feed applications and transgenic studies.
Original languageEnglish
Pages (from-to)190-197
Number of pages8
JournalApplied Microbiology and Biotechnology
Issue number2-3
Publication statusPublished - 22 Jul 2002

ASJC Scopus subject areas

  • Biotechnology
  • Microbiology
  • Bioengineering

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