Implementation of the agmatine-controlled expression system for inducible gene expression in Lactococcus lactis

[摘要] BackgroundLactococcus lactis has been safely consumed in fermented foods for millennia. This Gram-positive bacterium has now become of industrial importance as an expression host for the overproduction of lipopolysaccharide-free recombinant proteins used as food ingredients, therapeutic proteins and biotechnological enzymes.ResultsThis paper reports an agmatine-controlled expression (ACE) system for L. lactis, comprising the lactococcal agmatine-sensor/transcriptional activator AguR and its target promoter PaguB. The usefulness and efficiency of this system was checked via the reporter gene gfp and by producing PEP (Myxococcus xanthus prolyl-endopeptidase), an enzyme of biomedical interest able to degrade the immunotoxic peptides produced during the gastrointestinal breakdown of gluten.ConclusionThe ACE system developed in this work was suitable for the efficient expression of the functional recombinant proteins GFP and PEP. The expression system was tightly regulated by the agmatine concentration and allowed high protein production without leakiness.

[发布日期] 2015-12-30

[关键词] Lactococcus lactis;Expression vector;Agmatine induction;Myxococcus xanthus;Prolyl-endopeptidase