| Autor: |
Le DT; Université de Toulouse; INSA,UPS, INP; LISBP, Toulouse, France ; INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, Toulouse, France ; CNRS, UMR5504, Toulouse, France ; CNRS, LAAS, Toulouse, France ; CNRS, ITAV-UMS3039, Toulouse, France ; Université de Toulouse, LAAS, Toulouse, France., Tran TL, Duviau MP, Meyrand M, Guérardel Y, Castelain M, Loubière P, Chapot-Chartier MP, Dague E, Mercier-Bonin M |
| Jazyk: |
angličtina |
| Zdroj: |
PloS one [PLoS One] 2013 Nov 18; Vol. 8 (11), pp. e79850. Date of Electronic Publication: 2013 Nov 18 (Print Publication: 2013). |
| DOI: |
10.1371/journal.pone.0079850 |
| Abstrakt: |
Adhesion of bacteria to mucus may favor their persistence within the gut and their beneficial effects to the host. Interactions between pig gastric mucin (PGM) and a natural isolate of Lactococcus lactis (TIL448) were measured at the single-cell scale and under static conditions, using atomic force microscopy (AFM). In parallel, these interactions were monitored at the bacterial population level and under shear flow. AFM experiments with a L. lactis cell-probe and a PGM-coated surface revealed a high proportion of specific adhesive events (60%) and a low level of non-adhesive ones (2%). The strain muco-adhesive properties were confirmed by the weak detachment of bacteria from the PGM-coated surface under shear flow. In AFM, rupture events were detected at short (100-200 nm) and long distances (up to 600-800 nm). AFM measurements on pili and mucus-binding protein defective mutants demonstrated the comparable role played by these two surface proteinaceous components in adhesion to PGM under static conditions. Under shear flow, a more important contribution of the mucus-binding protein than the pili one was observed. Both methods differ by the way of probing the adhesion force, i.e. negative force contact vs. sedimentation and normal-to-substratum retraction vs. tangential detachment conditions, using AFM and flow chamber, respectively. AFM blocking assays with free PGM or O-glycan fractions purified from PGM demonstrated that neutral oligosaccharides played a major role in adhesion of L. lactis TIL448 to PGM. This study dissects L. lactis muco-adhesive phenotype, in relation with the nature of the bacterial surface determinants. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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