BACKGROUND Lactic acid bacteria (LAB) are receiving more attention to act as cell factories for the production of high-value metabolites. However, the molecular tools for genetic modifying these strains are mainly vector-based double-crossover strategies, which are laborious and inefficient. To address this problem, several counterselectable markers have been developed, while few of them could ...

BACKGROUND Proteinaceous bioactive substances and pharmaceuticals are most conveniently administered orally. However, the facing problems are the side effects of proteolytic degradation and denaturation in the gastrointestinal tract. In recent years, lactic acid bacteria (LAB) have been verified to be a promising delivery vector for susceptible functional proteins and drugs. KiSS-1 peptide, a c...

background and objectives: importance of development of novel probiotic fermented milk and challenge made for its acceptability is well known. in this research, the impact of different inoculation sizes of yogurt and dl-type starter culture (mesophilic and thermophilic lab) on titratable acidity, viscosity, sensorial and microbial properties of fermented milk was investigated; and finally, prob...

Adherence of F18 fimbrial Escherichia coli to porcine intestinal epithelial cells is mediated by the adhesin (FedF) of F18 fimbriae. In a previous study, we demonstrated the specificity of the amino acid residues between 60 and 109 as the receptor binding domain of FedF. In this study, different expression, secretion, and anchoring systems for the receptor binding domain of the FedF adhesin in ...

In the genome of Lactococcus lactis IL1403 five genes encoding peptidoglycan hydrolases are present: four glucosaminidases (acmA, acmB, acmC and acmD) and an endopeptidase (yjgB). Genes for six prophage lysins have also been identified. The genes acmB, acmC, acmD, yjgB and the lysin lytR of prophage r1t and the lytic gene of the prophage bIL309 were cloned downstream of the nisin-inducible prom...

this study evaluated the antimicrobial activities of two lactic acid bacteria, lactococcus lactis subsp. lactis i23 and lactococcus lactis subsp. lactis e91, against brochothrix thermosphacta in pork meat during storage at ambient temperature (30°c) for 168 h. the lab strains and the spoilage organism were inoculated on fresh pork samples at 1×106 cfug-1. results showed about 3 log reduction in...

Upon prolonged exposure to cholate and other toxic compounds, Lactococcus lactis develops a multidrug resistance phenotype that has been attributed to an elevated expression of the heterodimeric ABC-type multidrug transporter LmrCD. To investigate the molecular basis of bile acid resistance in L. lactis and to evaluate the contribution of efflux-based mechanisms in this process, the drug-sensit...

 In this study the forward and reverse primers were designated to amplify the segments (~250 bps and ~650 bps) of the gene coding domains 1 and 4 of aerolysin of Aeromonas hydrophila. These two domains are involved in pathogenesis of the aerolysin gene. Sequences for two restriction enzymes, Pst I and Hind III, were included in the forward and reverse primers respectively. These restriction enz...