Distinct cytoskeletal proteins define zones of enhanced cell wall synthesis in Helicobacter pylori
- University of Washington, United States
- Princeton University, United States
- Fred Hutchinson Cancer Research Center, United States
- University of Delaware, United States
- Harvard Medical School, United States
- Newcastle University, United Kingdom
- Indiana University, United States
Abstract
Helical cell shape is necessary for efficient stomach colonization by Helicobacter pylori, but the molecular mechanisms for generating helical shape remain unclear. The helical centerline pitch and radius of wild-type H. pylori cells dictate surface curvatures of considerably higher positive and negative Gaussian curvatures than those present in straight- or curved-rod H. pylori. Quantitative 3D microscopy analysis of short pulses with either N-acetylmuramic acid or D-alanine metabolic probes showed that cell wall growth is enhanced at both sidewall curvature extremes. Immunofluorescence revealed MreB is most abundant at negative Gaussian curvature, while the bactofilin CcmA is most abundant at positive Gaussian curvature. Strains expressing CcmA variants with altered polymerization properties lose helical shape and associated positive Gaussian curvatures. We thus propose a model where CcmA and MreB promote PG synthesis at positive and negative Gaussian curvatures, respectively, and that this patterning is one mechanism necessary for maintaining helical shape.
Data availability
The MATLAB scripts used to reconstruct cell surfaces and perform the geometric enrichment analyses are publicly available under a BSD 3-clause license at https://github.com/PrincetonUniversity/shae-cellshape-public and archived at https://doi.org/10.5281/zenodo.1248978.
Article and author information
Author details
Benjamin P Bratton
Funding
National Institutes of Health (R01 AI136946)
- Nina Reda Salama
National Science Foundation (DGE-1256082)
- Jennifer A Taylor
- Kris M Blair
Department of Defense (National Defense Science & Engineering Graduate Fellowship (NDSEG))
- Jennifer A Taylor
GO-MAP (Graduate Opportunity Program Research Assistantship Award)
- Sophie R Sichel
National Science Foundation (PHY-1734030)
- Benjamin P Bratton
- Josh W Shaevitz
Glenn Centers for Aging Research
- Benjamin P Bratton
National Institutes of Health (R21 AI121828)
- Benjamin P Bratton
- Josh W Shaevitz
National Institutes of Health (GM113172)
- Michael S VanNieuwenhze
National Institutes of Health (U01 CA221230)
- Catherine L Grimes
- Nina Reda Salama
National Institutes of Health (T32 CA009657)
- Kris M Blair
National Institutes of Health (T32 GM95421)
- Sophie R Sichel
National Institutes of Health (T32 GM008550)
- Kristen E DeMeester
National Institutes of Health (P30 CA015704)
- Nina Reda Salama
National Center for Research Resources (Stanford Imaging Award Number 1S10OD01227601)
- Nina Reda Salama
Wellcome (101824/Z/13/Z)
- Waldemar Vollmer
National Science Foundation (DGE-0718124)
- Jennifer A Taylor
The funders had no role in study design, datacollection and interpretation, or the decision to submit the work for publication. The opinions, findings, and conclusions or recommendationsexpressed in this material contents are solely the responsibility of the authors and do not necessarily represent the official views of the NCRR,the National Institutes of Health, the Department of Defense, or the National Science Foundation.
Copyright
© 2020, Taylor et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 4,333
- views
-
- 551
- downloads
-
- 52
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
A two-part list of links to download the article, or parts of the article, in various formats.
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Distinct cytoskeletal proteins define zones of enhanced cell wall synthesis in Helicobacter pylori
eLife 9:e52482.
https://doi.org/10.7554/eLife.52482
Further reading
-
- Ecology
- Microbiology and Infectious Disease
Interspecies interactions involving direct competition via bacteriocin production play a vital role in shaping ecological dynamics within microbial ecosystems. For instance, the ribosomally produced siderophore bacteriocins, known as class IIb microcins, affect the colonization of host-associated pathogenic Enterobacteriaceae species. Notably, to date, only five of these antimicrobials have been identified, all derived from specific Escherichia coli and Klebsiella pneumoniae strains. We hypothesized that class IIb microcin production extends beyond these specific compounds and organisms. With a customized informatics-driven approach, screening bacterial genomes in public databases with BLAST and manual curation, we have discovered 12 previously unknown class IIb microcins in seven additional Enterobacteriaceae species, encompassing phytopathogens and environmental isolates. We introduce three novel clades of microcins (MccW, MccX, and MccZ), while also identifying eight new variants of the five known class IIb microcins. To validate their antimicrobial potential, we heterologously expressed these microcins in E. coli and demonstrated efficacy against a variety of bacterial isolates, including plant pathogens from the genera Brenneria, Gibbsiella, and Rahnella. Two newly discovered microcins exhibit activity against Gram-negative ESKAPE pathogens, i.e., Acinetobacter baumannii or Pseudomonas aeruginosa, providing the first evidence that class IIb microcins can target bacteria outside of the Enterobacteriaceae family. This study underscores that class IIb microcin genes are more prevalent in the microbial world than previously recognized and that synthetic hybrid microcins can be a viable tool to target clinically relevant drug-resistant pathogens. Our findings hold significant promise for the development of innovative engineered live biotherapeutic products tailored to combat these resilient bacteria.
-
- Microbiology and Infectious Disease
Toxoplasma gondii is an intracellular parasite that subverts host cell functions via secreted virulence factors. Up to 70% of parasite-controlled changes in the host transcriptome rely on the MYR1 protein, which is required for the translocation of secreted proteins into the host cell. Mice infected with MYR1 knock-out (KO) strains survive infection, supporting a paramount function of MYR1-dependent secreted proteins in Toxoplasma virulence and proliferation. However, we have previously shown that MYR1 mutants have no growth defect in pooled in vivo CRISPR-Cas9 screens in mice, suggesting that the presence of parasites that are wild-type at the myr1 locus in pooled screens can rescue the phenotype. Here, we demonstrate that MYR1 is not required for the survival in IFN-γ-activated murine macrophages, and that parasites lacking MYR1 are able to expand during the onset of infection. While ΔMYR1 parasites have restricted growth in single-strain murine infections, we show that the phenotype is rescued by co-infection with wild-type (WT) parasites in vivo, independent of host functional adaptive immunity or key pro-inflammatory cytokines. These data show that the major function of MYR1-dependent secreted proteins is not to protect the parasite from clearance within infected cells. Instead, MYR-dependent proteins generate a permissive niche in a paracrine manner, which rescues ΔMYR1 parasites within a pool of CRISPR mutants in mice. Our results highlight an important limitation of otherwise powerful in vivo CRISPR screens and point towards key functions for MYR1-dependent Toxoplasma-host interactions beyond the infected cell.
