Helicobacter pylori strains vary cell shape and flagellum number to maintain robust motility in viscous environments

Laura E. Martínez, Joseph M. Hardcastle, Jeffrey Wang, Zachary Pincus, Jennifer Tsang, Timothy R. Hoover, Rama Bansil, Nina R. Salama

Research output: Contribution to journalArticlepeer-review

41 Scopus citations

Abstract

The helical shape of the human stomach pathogen Helicobacter pylori has been suggested to provide mechanical advantage for penetrating the viscous stomach mucus layer. Using single-cell tracking and quantitative morphology analysis, we document marked variation in cell body helical parameters and flagellum number among H. pylori strains leading to distinct and broad speed distributions in broth and viscous gastric mucin media. These distributions reflect both temporal variation in swimming speed and morphologic variation within the population. Isogenic mutants with straight-rod morphology showed 7-21% reduction in speed and a lower fraction of motile bacteria. Mutational perturbation of flagellum number revealed a 19% increase in speed with 4 versus 3 median flagellum number. Resistive force theory modeling incorporating variation of both cell shape and flagellum number predicts qualitative speed differences of 10-30% among strains. However, quantitative comparisons suggest resistive force theory underestimates the influence of cell body shape on speed for helical shaped bacteria.

Original languageEnglish
Pages (from-to)88-110
Number of pages23
JournalMolecular Microbiology
Volume99
Issue number1
DOIs
StatePublished - Jan 1 2016

Fingerprint

Dive into the research topics of 'Helicobacter pylori strains vary cell shape and flagellum number to maintain robust motility in viscous environments'. Together they form a unique fingerprint.

Cite this