Cloning, expression and characterization of a novel thermophilic polygalacturonase from Caldicellulosiruptor bescii DSM 6725.

ABSTRACT: We cloned the gene ACM61449 from anaerobic, thermophilic Caldicellulosiruptor bescii, and expressed it in Escherichia coli origami (DE3). After purification through thermal treatment and Ni-NTA agarose column extraction, we characterized the properties of the recombinant protein (CbPelA). The optimal temperature and pH of the protein were 72 °C and 5.2, respectively. CbPelA demonstrated high thermal-stability, with a half-life of 14 h at 70 °C. CbPelA also showed very high activity for polygalacturonic acid (PGA), and released monogalacturonic acid as its sole product. The Vmax and Km of CbPelA were 384.6 U·mg⁻¹ and 0.31 mg·mL⁻¹, respectively. CbPelA was also able to hydrolyze methylated pectin (48% and 10% relative activity on 20%-34% and 85% methylated pectin, respectively). The high the

SUBMITTER: Chen Y 

PROVIDER: S-EPMC4013591 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature