Surface proteins of Lactobacillus species

Kada je riječ o tehnološkim i zdravstvenim primjenama bakterija mliječne kiseline, sastav, struktura i komponente stanične stijenke, pogotovo površinski proteini, igraju glavne uloge. Stoga je cilj ovog rada bio dokazati prisutnost S-proteina i drugih površinskih proteina kod bakterijskih sojeva Lactobacillus helveticus M92, Lactobacillus brevis D6, Lactobacillus brevis ZG1, Lactobacillus brevis SF9B, Lactobacillus brevis SF15B i Lactobacillus plantarum D13. Provođenjem SDS-PAGE elektroforeze površinskih proteina dokazana je prisutnost Sproteina i SLAP (eng. Surface-Layer Associated Proteins). Potvrda prisutnosti S-proteina provedena je detekcijom gena koji kodiraju za S-proteine. Provedenom PCR reakcijom sa sojevima L. helveticus M92, L. brevis D6, L. brevis ZG1, L. brevis SF9B i L. brevis SF15B, s početnicama Sprot 1 i Sprot 2, a potom i DNA elektroforezom PCR produkata dobiveni su pozitivni signali za sve ispitivane Lactobacillus sojeve što ukazuje da su odabrane specifične početnice pogodne za detekciju gena koji kodiraju za površinske S-proteine.When it comes to technological and health applications of lactic acid bacteria, the composition, structure and components of the cell wall, especially surface proteins, play the main roles. Therefore, the aim of this thesis was to prove the presence of S-layer and other surface proteins in bacterial strains of Lactobacillus helveticus M92, Lactobacillus brevis D6, Lactobacillus brevis ZG1, Lactobacillus brevis SF9B, Lactobacillus brevis SF15B and Lactobacillus plantarum D13. S-protein and SLAP (Surface-Layer Associated Proteins) were detected by SDS-PAGE electrophoresis of the surface proteins. Confirmation of the presence of S-protein was performed by detection of genes encoding S-proteins. PCR reaction with strains of L. helveticus M92, L. brevis D6, L. brevis ZG1, L. brevis SF9B and L. brevis SF15B with primers Sprot 1 and Sprot 2, and then DNA electrophoresis of PCR products gave the positive signals for all tested Lactobacillus strains which indicate that selected specific primers are suitable for the detection of genes encoding surface S-proteins