%0 Journal Article %T A cell wall‐associated polysaccharide is required for bacteriophage adsorption to the Streptococcus thermophilus cell surface %+ Transfrontalière BioEcoAgro - UMR 1158 (BioEcoAgro) %A Mcdonnell, Brian %A Hanemaaijer, Laurens %A Bottacini, Francesca %A Kelleher, Philip %A Lavelle, Katherine %A Sadovskaya, Irina %A Vinogradov, Evgeny %A Ver Loren van Themaat, Emiel %A Kouwen, Thijs %A Mahony, Jennifer %A Sinderen, Douwe %< avec comité de lecture %@ 0950-382X %J Molecular Microbiology %I Wiley %V 114 %P 31 - 45 %8 2020-03-05 %D 2020 %R 10.1111/mmi.14494 %K adsorption dairy mutation NMR polysaccharide structure %K adsorption %K dairy %K mutation %K NMR %K polysaccharide %K structure %Z Life Sciences [q-bio]Journal articles %X Streptococcus thermophilus strain ST64987 was exposed to a member of a recently discovered group of S. thermophilus phages (the 987 phage group), generating phageinsensitive mutants, which were then characterized phenotypically and genomically. Decreased phage adsorption was observed in selected bacteriophage-insensitive mutants, and was partnered with a sedimenting phenotype and increased cell chain length or aggregation. Whole genome sequencing of several bacteriophage-insensitive mutants identified mutations located in a gene cluster presumed to be responsible for cell wall polysaccharide production in this strain. Analysis of cell surface-associated glycans by methylation and NMR spectroscopy revealed a complex branched rhamno-polysaccharide in both ST64987 and phage-insensitive mutant BIM3. In addition, a second cell wall-associated polysaccharide of ST64987, composed of hexasaccharide branched repeating units containing galactose and glucose, was absent in the cell wall of mutant BIM3. Genetic complementation of three phage-resistant mutants was shown to restore the carbohydrate and phage resistance profiles of the wild-type strain, establishing the role of this gene cluster in cell wall polysaccharide production and phage adsorption and, thus, infection. %G English %L hal-04049354 %U https://ulco.hal.science/hal-04049354 %~ UNIV-ARTOIS %~ UNIV-LITTORAL %~ UNIV-LILLE %~ INRAE %~ UNIV-CATHOLILLE %~ BIOECOAGRO-ULCO