Surface glycosaminoglycans mediate adherence between HeLa cells and Lactobacillus salivarius Lv72
1 Área de Microbiología, Universidad de Oviedo, Julián Clavería 6 33006 Oviedo, Spain
2 Instituto Universitario de Biotecnología, Universidad de Oviedo, Oviedo, Spain
3 Instituto de Productos Lacteos de Asturias (IPLA-CSIC), Villaviciosa, Spain
4 Instituto Univesitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, Oviedo, Spain
BMC Microbiology 2013, 13:210 doi:10.1186/1471-2180-13-210Published: 17 September 2013
The adhesion of lactobacilli to the vaginal surface is of paramount importance to develop their probiotic functions. For this reason, the role of HeLa cell surface proteoglycans in the attachment of Lactobacillus salivarius Lv72, a mutualistic strain of vaginal origin, was investigated.
Incubation of cultures with a variety of glycosaminoglycans (chondroitin sulfate A and C, heparin and heparan sulfate) resulted in marked binding interference. However, no single glycosaminoglycan was able to completely abolish cell binding, the sum of all having an additive effect that suggests cooperation between them and recognition of specific adhesins on the bacterial surface. In contrast, chondroitin sulfate B enhanced cell to cell attachment, showing the relevance of the stereochemistry of the uronic acid and the sulfation pattern on binding. Elimination of the HeLa surface glycosaminoglycans with lyases also resulted in severe adherence impairment. Advantage was taken of the Lactobacillus-glycosaminoglycans interaction to identify an adhesin from the bacterial surface. This protein, identify as a soluble binding protein of an ABC transporter system (OppA) by MALDI-TOF/(MS), was overproduced in Escherichia coli, purified and shown to interfere with L. salivarius Lv72 adhesion to HeLa cells.
These data suggest that glycosaminoglycans play a fundamental role in attachment of mutualistic bacteria to the epithelium that lines the cavities where the normal microbiota thrives, OppA being a bacterial adhesin involved in the process.