Genetic improvement of alpha-amylase producing Bacillus licheniformis by homolog-mediated alpha-amylase gene amplification

Sheng Wu Gong Cheng Xue Bao. 2009 Mar;25(3):375-80.

Abstract

Bacillus licheniformis alpha-amylase (BLA) is one of the most important enzymes involved in starch hydrolysis and many biotechnological processes. To improve the BLA productivity, an integrative plasmid pBL-amyL carrying amyL gene encoding a thermophilic alpha-amylase of B. licheniformis was constructed and transformed into B. licheniformis B0204, an industrial alpha-amylase producer. The transformants harboring different copies of amyL were developed on kanamycin by using homolog-mediated chromosomal amplification of alpha-amylase gene. The recombinants with different multiple copies of amyL integrated in the chromosome were identified by real-time PCR and evaluated by shake-flask fermentation. Recombinants harboring 2-5 multiple copies of amyL produced more alpha-amylase comparison to the parental strain B0204.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacillus / enzymology
  • Bacillus / genetics*
  • Gene Amplification*
  • Industrial Microbiology*
  • Nucleic Acid Amplification Techniques
  • Transformation, Genetic
  • alpha-Amylases / biosynthesis*
  • alpha-Amylases / genetics*

Substances

  • alpha-Amylases
  • alpha-amylase, Bacillus licheniformis