Phenotypic, genomic, and transcriptional characterization of Streptococcus pneumoniae interacting with human pharyngeal cells

BMC Genomics

Research Article

Luke J Tallon¹  Nikhil Kumar¹  Nadeeza Ishmael¹  Xinyue Liu¹  Todd H Creasy¹  Umar Farooq¹  David R Riley¹  Hervé Tettelin¹  Julie C Dunning Hotopp¹  Susan K Hollingshead²  George M Carlone³  Sandra Romero-Steiner³  Jacquelyn Sampson³  Cynthia S Goldsmith⁴  Sheila Z Kimaro Mlacha⁵  J Anthony G Scott⁶ 

[1] Department of Microbiology and Immunology, Institute for Genome Sciences, University of Maryland School of Medicine, 801 W. Baltimore Street, 21201, Baltimore, MD, USA;Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA;Division of Bacterial Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA;Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta, GA, USA;Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya;Department of Microbiology and Immunology, Institute for Genome Sciences, University of Maryland School of Medicine, 801 W. Baltimore Street, 21201, Baltimore, MD, USA;Respiratory & Meningeal Pathogens Research Unit, University of the Witwatersrand/Medical Research Council, Johannesburg, South Africa;Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya;Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK;

关键词: Streptococcus pneumoniae;    Gene expression;    Microarray;    Adherence;    Invasion;    Genome;    Mutagenesis;    SP_1922;    Ply;   

DOI  :  10.1186/1471-2164-14-383

 received in 2012-10-10, accepted in 2013-05-24,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundStreptococcus pneumoniae is a leading cause of childhood morbidity and mortality worldwide, despite the availability of effective pneumococcal vaccines. Understanding the molecular interactions between the bacterium and the host will contribute to the control and prevention of pneumococcal disease.ResultsWe used a combination of adherence assays, mutagenesis and functional genomics to identify novel factors involved in adherence. By contrasting these processes in two pneumococcal strains, TIGR4 and G54, we showed that adherence and invasion capacities vary markedly by strain. Electron microscopy showed more adherent bacteria in association with membranous pseudopodia in the TIGR4 strain. Operons for cell wall phosphorylcholine incorporation (lic), manganese transport (psa) and phosphate utilization (phn) were up-regulated in both strains on exposure to epithelial cells. Pneumolysin, pili, stress protection genes (adhC-czcD) and genes of the type II fatty acid synthesis pathway were highly expressed in the naturally more invasive strain, TIGR4. Deletion mutagenesis of five gene regions identified as regulated in this study revealed attenuation in adherence. Most strikingly, ∆SP_1922 which was predicted to contain a B-cell epitope and revealed significant attenuation in adherence, appeared to be expressed as a part of an operon that includes the gene encoding the cytoplasmic pore-forming toxin and vaccine candidate, pneumolysin.ConclusionThis work identifies a list of novel potential pneumococcal adherence determinants.

【 授权许可】

Unknown   
© Kimaro Mlacha et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.