title: A novel system of cytoskeletal elements in the human pathogen Helicobacter pylori.
abstract: Pathogenicity of the human pathogen Helicobacter pylori relies upon its capacity to adapt to a hostile environment and to escape from the host response. Therefore, cell shape, motility, and pH homeostasis of these bacteria are specifically adapted to the gastric mucus. We have found that the helical shape of H. pylori depends on coiled coil rich proteins (Ccrp), which form extended filamentous structures in vitro and in vivo, and are differentially required for the maintenance of cell morphology. We have developed an in vivo localization system for this pathogen. Consistent with a cytoskeleton-like structure, Ccrp proteins localized in a regular punctuate and static pattern within H. pylori cells. Ccrp genes show a high degree of sequence variation, which could be the reason for the morphological diversity between H. pylori strains. In contrast to other bacteria, the actin-like MreB protein is dispensable for viability in H. pylori, and does not affect cell shape, but cell length and chromosome segregation. In addition, mreB mutant cells displayed significantly reduced urease activity, and thus compromise a major pathogenicity factor of H. pylori. Our findings reveal that Ccrp proteins, but not MreB, affect cell morphology, while both cytoskeletal components affect the development of pathogenicity factors and/or cell cycle progression.
authors: Department of Medical Microbiology and Hygiene, Institute of Medical Microbiology and Hygiene, University Hospital Freiburg, Freiburg, Germany. barbara.waidner@uniklinik-freiburg.de
authors: Barbara
authors: B
authors: Waidner
authors: Mara
authors: M
authors: Specht
authors: Felix
authors: F
authors: Dempwolff
authors: Katharina
authors: K
authors: Haeberer
authors: Sarah
authors: S
authors: Schaetzle
authors: Volker
authors: V
authors: Speth
authors: Manfred
authors: M
authors: Kist
authors: Peter L
authors: PL
authors: Graumann
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D002453:Cell Cycle / Q000502:physiology; D002465:Cell Movement / Q000502:physiology; D048430:Cell Shape / Q000502:physiology; D003599:Cytoskeleton / Q000378:metabolism*; D016480:Helicobacter pylori / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D006863:Hydrogen-Ion Concentration; D014510:Urease / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D014510:Urease