Abstrato

S-layer proteins and bacteriocins in probiotics as living drugs - impact on microbiota

Blazenka kos, Katarina zoric, martina banic, andreja lebos pavunc, ksenija uroic, jasna novak and jagoda suskovic

 S-layer proteins and bacteriocin synthesis were tested in a large sample of autochthonous lactic acid bacteria (LAB). Only four Lactobacillus brevis strains express S-layer proteins, according to analyses of bacterial surface proteins using SDS-PAGE, 2D-PAGE, and PCR with specific primers for slp genes, while only three Lactobacillus plantarum strains were confirmed as bacteriocin producers using antibacterial activity assays and PCR with specific primers for genes encoding various bacteriocins. Although the biological activities of Lactobacillus S-layer proteins are unknown, our findings show that they mediate bacterial adhesion to intestinal epithelial cells and extracellular matrix proteins, as well as regulate the immune response, both of which are significant probiotic features. When employed as a mixed culture, the S-layer protein carrying strain and the bacteriocin generating strain had a significant impact on the microbiota composition of rats used as Alzheimer's disease animal models. Purified S-layer proteins from the L. brevis SF9B strain were discovered using the LC/MS technique, with a MW of 50.9 kDa and a pI of 9.54, and their secondary structure was predicted using I-TASSER modelling. The fact that pure S-layers are stable at non-physiological pH and protect cells from a variety of stresses offers up an intriguing possibility in the creation of vehicles for the oral delivery of pharmaceuticals or vaccinations, especially given LAB's GRAS status (Generally Regarded as Safe). Publications of Late 1. eme H., Bogovi Matijai B., Vigelj K., Langerholc T., Fujs S., Horvat J., Zlati E., Gjurai K., Petkovi H., tempelj M., Kos B., ukovi J., Kosec G. (2017) Generation of Lactobacillus plantarum strains with improved potential to target gastrointestinal disorders related to sugar malabsorption. Food Research. Hana Uranská, Peter Raspor, Ksenija Uroi, Nataa Goli, Blaenka Kos, Sanja Mihajlovi, Jelena Begovi, Jagoda Ukovi, Ljubia Topisirovi, and Nea Ade (2016) Folia Microbiol, Characterization of the yeast and mould biota in traditional white pickled cheeses using culture-dependent and independent molecular methods. 61:455–463. 3. Uroi?, K., Beganovi?, J., Hynönen, U., Pietilä, T. E., Leboš Pavunc, A., Kant, R., Kos, B., Palva, A., Šuškovi?, J. (2016) The role of S-layer in adhesive and immunological properties of probiotic starter culture Lactobacillus brevis D6 isolated from artisanal smoked fresh cheese. LWT - Food Sci. Technol. 69: 623-632. 4. M. Ga?i?, N. Biland?i?, ?. Ivanec Šipuši?, M. Petrovi?, B. Kos, N. Vah?i?, J. Šuškovi? (2015) Degradation of Oxytetracycline, Streptomycin, Sulphathiazole and Chloramphenicol Residues in Different Types of Honey, Food Technol. Biotechnol. 53 (2) 154–162. 5. M. Zivkovic, N. Cadez, K. Uroic, M. Miljkovic, M. Tolinacki, P. Dousova, B. Kos, J. Suskovic, P. Raspor, Lj. Topisirovic, N. Golic (2015) Evaluation of probiotic potential of yeasts isolated from traditional cheeses manufactured in Serbia and Croatia,