Characterization of gtf, a Glucosyltransferase Gene in the Genomes of Pediococcus parvulus and Oenococcus oeni, Two Bacterial Species Commonly Found in Wine

• Published in: Applied and Environmental Microbiology 2008-07, Vol.74 (13), p.4079-4090
• Main Authors: Dols-Lafargue, Marguerite, Lee, Hyo Young, Le Marrec, Claire, Heyraud, Alain, Chambat, Gérard, Lonvaud-Funel, Aline
• Format: Article
• Language: English
• Subjects: Bacteria; Bacterial Adhesion; beta-Glucans - metabolism; Biological and medical sciences; Cells; Ecology, environment; Food Microbiology; Fundamental and applied biological sciences. Psychology; Genomics; Glucosyltransferases - genetics; Glucosyltransferases - metabolism; Gram-Positive Cocci - enzymology; Gram-Positive Cocci - genetics; Heat-Shock Response; Industrial Microbiology; Life Sciences; Microbiology; Molecular Sequence Data; Mutation; Oenococcus oeni; Pediococcus - enzymology; Pediococcus - genetics; Pediococcus parvulus; Polymerase Chain Reaction; Protein synthesis; Recombinant Proteins - genetics; Recombinant Proteins - metabolism; Reverse Transcriptase Polymerase Chain Reaction; Sequence Analysis, DNA; Vitaceae; Wine - microbiology; Wines
• ISSN: 0099-2240; 1098-5336; 1098-6596
• DOI: 10.1128/AEM.00673-08

"Ropiness" is a bacterial alteration in wines, beers, and ciders, caused by β-glucan-synthesizing pediococci. A single glucosyltransferase, Gtf, controls ropy polysaccharide synthesis. In this study, we show that the corresponding gtf gene is also present on the chromosomes of several strains of Oenococcus oeni isolated from nonropy wines. gtf is surrounded by mobile elements that may be implicated in its integration into the chromosome of O. oeni. gtf is expressed in all the gtf⁺ strains, and β-glucan is detected in the majority of these strains. Part of this β-glucan accumulates around the cells forming a capsule, while the other part is liberated into the medium together with heteropolysaccharides. Most of the time, this polymer excretion does not lead to ropiness in a model medium. In addition, we show that wild or recombinant bacterial strains harboring a functional gtf gene (gtf⁺) are more resistant to several stresses occurring in wine (alcohol, pH, and SO₂) and exhibit increased adhesion capacities compared to their gtf mutant variants.