Panel 4 : Report of the Microbiology Panel

Objective. To perform a comprehensive review of the literature from July 2011 until June 2015 on the virology and bacteriology of otitis media in children. Data Sources. PubMed database of the National Library of Medicine. Review Methods. Two subpanels comprising experts in the virology and bacteriology of otitis media were created. Each panel reviewed the relevant literature in the fields of virology and bacteriology and generated draft reviews. These initial reviews were distributed to all panel members prior to meeting together at the Post-symposium Research Conference of the 18th International Symposium on Recent Advances in Otitis Media, National Harbor, Maryland, in June 2015. A final draft was created, circulated, and approved by all panel members. Conclusions. Excellent progress has been made in the past 4 years in advancing our understanding of the microbiology of otitis media. Numerous advances were made in basic laboratory studies, in animal models of otitis media, in better understanding the epidemiology of disease, and in clinical practice. Implications for Practice. (1) Many viruses cause acute otitis media without bacterial coinfection, and such cases do not require antibiotic treatment. (2) When respiratory syncytial virus, metapneumovirus, and influenza virus peak in the community, practitioners can expect to see an increase in clinical otitis media cases. (3) Biomarkers that predict which children with upper respiratory tract infections will develop otitis media may be available in the future. (4) Compounds that target newly identified bacterial virulence determinants may be available as future treatment options for children with otitis media.Peer reviewe

Mol Biotechnol

Oenococcus oeni is the main bacterial species that drives malolactic fermentation in wine. Most O. oeni strains produce capsular exopolysaccharides (EPS) that may contribute to protect them in the wine hostile environment. In O. oeni genome sequences, several genes are predicted to encode priming glycosyltransferases (pGTs). These enzymes are essential for EPS formation as they catalyze the first biosynthetic step through the formation of a phosphoanhydride bond between a hexose-1-phosphate and a lipid carrier undecaprenyl phosphate. In many microorganisms, mutations abolishing the pGT activity also abolish the EPS formation. We first made an in silico analysis of all the genes encoding putative pGT over 50 distinct O. oeni genome sequences. Two polyisoprenyl-phosphate-hexose-1-phosphate transferases, WoaA and WobA, and a glycosyltransferase (It3) were particularly examined for their topology and amino acid sequence. Several isoforms of these enzymes were then expressed in E. coli, and their substrate specificity was examined in vitro. The substrate specificity varied depending on the protein isoform examined, and several mutations were shown to abolish WobA activity but not EPS synthesis. Further analysis of woaA and wobA gene expression levels suggests that WoaA could replace the deficient WobA and maintain EPS formation