New approaches to achieve high level enzyme production in Streptomyces lividans

作者：Sevillano Laura; Vijgenboom Erik; van Wezel Gilles P; Diaz Margarita; Santamaria Ramon I

来源：Microbial Cell Factories, 2016, 15(1): 28.

DOI：10.1186/s12934-016-0425-7

• Streptomyces
• Protein production
• Xylanase
• Amylase
• Laccase
• Vector optimization

Background: Actinomycetes are saprophytic soil bacteria, and a rich source of industrial enzymes. While some of these enzymes can be produced using well-characterized production platforms such as Escherichia coli or Bacillus subtilis, Streptomyces lividans may be the preferred host for proper folding and efficient secretion of active enzymes. A combination of promoters, signal peptides and hosts were tested in order to obtain the best protein expression in this actinomycete. The xylanase, Xys1, from S. halstedii, the a-amylase, Amy, from S. griseus and the small laccase, SLAC, from S. coelicolor were used as reporters.
Results: The promoters xysAp from S. halstedii JM8 and pstSp from S. lividans were the most efficient among those tested. An improvement of 17 % was obtained in xylanase activity when the signal peptide of the a-amylase protein (Amy) of S. griseus IMRU3570 was used to direct its secretion. Enhanced expression of SsgA, a protein that plays a role in processes that require cell-wall remodelling, resulted in a improvement of 40 and 70 % of xylanase and amylase production, respectively. Deletion of genes SLI7232 and SLI4452 encoding putative repressors of xysAp provided improvement of production up to 70 % in the SLI7232 deletion strain. However, full derepression of this promoter activity was not obtained under the conditions assayed.
Conclusions: Streptomyces lividans is a frequently used platform for industrial enzyme production and a rational strain-development approach delivered significant improvement of protein production by this host.

• 出版日期2016-2-4