GENES AND MOLECULAR MECHANISMS PROMOTING PROBIOTIC ACTIVITY OF LACTIC ACID BACTERIA FROM WESTERN BALKAN

Lactic acid bacteria (LAB) play a key role in the production of different fermented food products and they are generally regarded as safe microorganisms. Fermented products manufactured in distinct ecological localities of Western Balkan are potential source of LAB with probiotic properties. Some LAB species are also normal microflora of gastrointestinal (GIT) and urogenital (UGT) tract where they through different mechanisms have beneficial influence on human and animal health, and are considered as probiotics. Since probiotic LAB have the ability to adhere to GIT and UGT epithelium, they play an important role and exhibit a great influence on physiology of the host. For the application of LAB as probiotics, it is essential to understand molecular mechanisms underlying the synthesis of exopolysaccharides, proteinases and antimicrobial substances, as well as aggregation potential of strains. For this purpose, additional systems for the genetic manipulations in LAB will be developed. This approach enables cloning of genes involved in the probiotic properties and studying of the relation between the cloned gene and the probiotic activity of the strain. Moreover, it is also important to understand the molecular mechanisms of potential resistance to antibiotics, as well as their dissemination among pathogenic and non-pathogenic bacteria including LAB. Additionally, studies on bacterial interactions and bacteria-host interactions represent one of the aims of this project.