Article,
Heterologous gene expression in Lactococcus lactis; expression of the Azotobacter vinelandii algE6 gene product displaying mannuronan C-5 epimerase activity.
FEMS Microbiol. Lett., 227 (2): 229-35 (2003)
Abstract
The Azotobacter vinelandii mannuronan C-5 epimerases AlgE1-7 can be
used to improve the properties of the commercially important polysaccharide
alginate that is widely used in a variety of products, such as food
and pharmaceuticals. Since lactic acid bacteria are generally regarded
as safe, they are attractive candidates for production of the epimerases.
A. vinelandii genes are GC-rich, in contrast to those of lactic acid
bacteria, but we show here that significant expression levels of
the epimerase AlgE6 can be obtained in Lactococcus lactis using the
nisin-controlled expression system. A 1200-fold induction ratio was
obtained resulting in an epimerase activity of 23900 dpm mg(-1) h(-1),
using a tritiated alginate substrate. The epimerase was detected
by Western blotting and nuclear magnetic resonance spectroscopy analysis
of its reaction product showed that the enzyme displayed catalytic
properties similar to those produced in Escherichia coli.
Tags
- *gene
- ;
- alginates/metabolism
- azotobacter
- bacterial
- blotting,
- carbohydrate
- epimerases/genetics/*metabolism
- expression
- gov't
- lactis/genetics/*metabolism
- lactococcus
- non-u.s.
- proteins/metabolism
- recombinant
- regulation,
- research
- support,
- vinelandii/*genetics
- western
