Genetic improvement of alpha-amylase producing Bacillus licheniformis by homolog-mediated alpha-amylase gene amplification.
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.
Niu
Dandan
D
Center for Bioresource and Bioenergy, School of Biotechnology and the Key Laboratory of Industrial Biotechnology of the Ministry of Education, Jiangnan University, Wuxi 214122, China.
Shi
Guiyang
G
Wang
Zhengxiang
Z
D001407:Bacillus / Q000201:enzymology / Q000235:genetics*; D005784:Gene Amplification; D007218:Industrial Microbiology; D021141:Nucleic Acid Amplification Techniques; D014170:Transformation, Genetic; D000516:alpha-Amylases / Q000096:biosynthesis* / Q000235:genetics*
D000516:alpha-Amylases; C501919:alpha-amylase, Bacillus licheniformis