A promoter probe vector, pTG244, was constructed with the aim of isolating transcription initiation signals from Streptococcus thermophilus (Streptococcus salivarius subsp. thermophilus). pTG244 is based on the Escherichia coli-streptococcus shuttle vector pTG222, into which the promoterless chloramphenicol acetyltransferase gene of Bacillus pumilus (cat-86) was cloned. Random Sau3A fragments f...

For reasons of efficiency Escherichia coli is used today as the microbial factory for production of plasmid DNA vaccines. To avoid hazardous antibiotic resistance genes and endotoxins from plasmid systems used nowadays, we have developed a system based on the food-grade Lactococcus lactis and a plasmid without antibiotic resistance genes. We compared the L. lactis system to a traditional one in...

Previous studies have demonstrated that milk fermented by specific Lactococcus lactis strains significantly inhibits the activity of angiotensin I-converting enzyme (ACE). However, the relationship between the ACE inhibitor and its in vivo action has revealed discrepancies. Therefore, the aim of the present study was to investigate the antihypertensive and heart rate (HR)-lowering effect of mil...

The Ll.LtrB group II intron from the low-G+C gram-positive bacterium Lactococcus lactis was the first bacterial group II intron shown to splice and mobilize in vivo. This retroelement interrupts the relaxase gene (ltrB) of three L. lactis conjugative elements: plasmids pRS01 and pAH90 and the chromosomal sex factor. Conjugative transfer of a plasmid harboring a segment of the pRS01 conjugative ...

The gene pepV, encoding a dipeptidase from Lactococcus lactis subsp. cremoris MG1363, was identified in a genomic library in pUC19 in a peptidase-deficient Escherichia coli strain and subsequently sequenced. PepV of L. lactis is enzymatically active in E. coli and hydrolyzes a broad range of dipeptides but no tri-, tetra-, or larger oligopeptides. Northern (RNA) and primer extension analyses in...

To achieve high mannitol production by Lactococcus lactis, the mannitol 1-phosphatase gene of Eimeria tenella and the mannitol 1-phosphate dehydrogenase gene mtlD of Lactobacillus plantarum were cloned in the nisin-dependent L. lactis NICE overexpression system. As predicted by a kinetic L. lactis glycolysis model, increase in mannitol 1-phosphate dehydrogenase and mannitol 1-phosphatase activi...

Lactococcus lactis plant isolates identifies adaptation mechanisms to the plant niche Running title: Genotype-phenotype matching of L. lactis plant isolates ABSTRACT Lactococcus lactis is a primary constituent of many starter cultures used for the manufacturing of fermented dairy products, but the species also occurs in various non-dairy niches such as (fermented) plant material. Three genome s...

Lactococcus lactis cremoris infections are very rare in humans. We experienced liver abscess and empyema due to L. lactis cremoris in an immunocompetent adult. A 42-yr-old man was admitted with fever and abdominal pain. Abdominal computed tomography (CT) revealed a liver abscess and chest CT showed loculated pleural effusion consistent with empyema. L. lactis cremoris was isolated from culture ...

Bacterial-based systems as live vectors for the delivery of heterologous antigens offer a number of advantages as vaccination strategies. Developments in genetic engineering have given Gram-positive lacticacid bacteria (LAB) the advantage of being used as a host expression system for antigen delivery to inducethe immune response. A fragment containing the full length of the “eprA1” ...

The genetic determinant (pepXP) of an X-prolyl dipeptidyl aminopeptidase (PepXP) has recently been cloned and sequenced from both Lactococcus lactis subsp. cremoris (B. Mayo, J. Kok, K. Venema, W. Bockelmann, M. Teuber, H. Reinke, and G. Venema, Appl. Environ. Microbiol. 57:38-44, 1991) and L. lactis subsp. lactis (M. Nardi, M.-C. Chopin, A. Chopin, M.-M. Cals, and J.-C. Gripon, Appl. Environ. ...