title: Assessment of in vitro biofilm formation by Helicobacter pylori.
abstract: OBJECTIVE
  Biofilms are surface-bound communities of bacterial cells that are implicated in their survival. As with various bacteria studied to date, Helicobacter pylori can have an alternate lifestyle as a biofilm. We previously reported that strain TK1402 showed a strong biofilm-forming ability in vitro. However, the mechanisms of its biofilm development remain unclear. We analyzed the basic characteristics of the biofilm-forming ability in strain TK1402.
  
  
  METHODS
  In order to characterize the biofilm-forming ability of the H. pylori strains, auto-aggregation, motility and hydrophobicity, which are important factors in biofilm formation by other bacteria, were analyzed. Further, we tested whether cell growth participated in biofilm formation in strain TK1402.
  
  
  RESULTS
  There were no significant differences in the auto-aggregation, motility and hydrophobicity of strain TK1402 compared with the other strains. On the other hand, pre-culture of this strain for 24-48 h resulted in decreased biofilm formation.
  
  
  CONCLUSIONS
  TK1402 is a strong biofilm-forming strain of H. pylori in Brucella broth supplemented with 7% fetal calf serum. It is possible that biofilm-forming cell growth is a principal factor in biofilm development.
authors.affiliation: Department of Infectious Disease, Kyorin University School of Medicine, Shinkawa, Tokyo, Japan. yonezawa@ks.kyorin-u.ac.jp
authors.forename: Hideo
authors.initials: H
authors.lastname: Yonezawa
authors.forename: Takako
authors.initials: T
authors.lastname: Osaki
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kurata
authors.forename: Cynthia
authors.initials: C
authors.lastname: Zaman
authors.forename: Tomoko
authors.initials: T
authors.lastname: Hanawa
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kamiya
mesh_terms: D001422:Bacterial Adhesion; D018441:Biofilms; D049109:Cell Proliferation; D016481:Helicobacter Infections / Q000382:microbiology*; D016480:Helicobacter pylori / Q000254:growth & development* / Q000302:isolation & purification; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007564:Japan; D007700:Kinetics