title: Comparative Genomics Revealed Multiple Helicobacter pylori Genes Associated with Biofilm Formation In Vitro.
abstract: BACKGROUND
  Biofilm formation by Helicobacter pylori may be one of the factors influencing eradication outcome. However, genetic differences between good and poor biofilm forming strains have not been studied.
  
  
  METHODS
  Biofilm yield of 32 Helicobacter pylori strains (standard strain and 31 clinical strains) were determined by crystal-violet assay and grouped into poor, moderate and good biofilm forming groups. Whole genome sequencing of these 32 clinical strains was performed on the Illumina MiSeq platform. Annotation and comparison of the differences between the genomic sequences were carried out using RAST (Rapid Annotation using Subsystem Technology) and SEED viewer. Genes identified were confirmed using PCR.
  
  
  RESULTS
  Genes identified to be associated with biofilm formation in H. pylori includes alpha (1,3)-fucosyltransferase, flagellar protein, 3 hypothetical proteins, outer membrane protein and a cag pathogenicity island protein. These genes play a role in bacterial motility, lipopolysaccharide (LPS) synthesis, Lewis antigen synthesis, adhesion and/or the type-IV secretion system (T4SS). Deletion of cagA and cagPAI confirmed that CagA and T4SS were involved in H. pylori biofilm formation.
  
  
  CONCLUSIONS
  Results from this study suggest that biofilm formation in H. pylori might be genetically determined and might be influenced by multiple genes. Good, moderate and poor biofilm forming strain might differ during the initiation of biofilm formation.
authors.affiliation: Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Eric Hong Jian
authors.initials: EH
authors.lastname: Wong
authors.affiliation: Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
authors.forename: Chow Goon
authors.initials: CG
authors.lastname: Ng
authors.affiliation: The Marshall Centre for Infectious Diseases Research and Training, School of Pathology and Laboratory Medicine (M502), University of Western Australia, Perth, Australia.
authors.forename: Eng Guan
authors.initials: EG
authors.lastname: Chua
authors.affiliation: The Marshall Centre for Infectious Diseases Research and Training, School of Pathology and Laboratory Medicine (M502), University of Western Australia, Perth, Australia.
authors.forename: Alfred Chin Yen
authors.initials: AC
authors.lastname: Tay
authors.affiliation: The Marshall Centre for Infectious Diseases Research and Training, School of Pathology and Laboratory Medicine (M502), University of Western Australia, Perth, Australia.
authors.forename: Fanny
authors.initials: F
authors.lastname: Peters
authors.affiliation: The Marshall Centre for Infectious Diseases Research and Training, School of Pathology and Laboratory Medicine (M502), University of Western Australia, Perth, Australia.|UM Marshall Centre, High Impact Research Building, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Barry J
authors.initials: BJ
authors.lastname: Marshall
authors.affiliation: Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
authors.forename: Bow
authors.initials: B
authors.lastname: Ho
authors.affiliation: Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Khean Lee
authors.initials: KL
authors.lastname: Goh
authors.affiliation: Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Jamuna
authors.initials: J
authors.lastname: Vadivelu
authors.affiliation: Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Mun Fai
authors.initials: MF
authors.lastname: Loke
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D018441:Biofilms / Q000254:growth & development*; D016680:Genome, Bacterial; D023281:Genomics / Q000379:methods*; D016480:Helicobacter pylori / Q000145:classification / Q000235:genetics / Q000502:physiology*; D059014:High-Throughput Nucleotide Sequencing; D066298:In Vitro Techniques; D017422:Sequence Analysis, DNA
chemical_list: D001426:Bacterial Proteins