See the published version of this article at BMC Microbiology.
This is a preprint, a preliminary version of a manuscript that has not completed peer review at a journal. Research Square does not conduct peer review prior to posting preprints. The posting of a preprint on this server should not be interpreted as an endorsement of its validity or suitability for dissemination as established information or for guiding clinical practice.
Learn more about In Review
Research article
Enterohaemorrhagic Escherichia coli activates nitrate respiration to benefit from the inflammatory response for initiation of microcolony-formation
Toru Tobe
Corresponding Author
ORCiD: https://orcid.org/0000-0002-1727-3174
License:
This work is licensed under a CC BY 4.0 License. Read Full License
View the published version at BMC Microbiology.
Background: For successful colonization, enterohaemorrhagic Escherichia coli (EHEC) injects virulence factors, called effectors, into target cells through the type three secretion system (T3SS), which is composed of a needle and basal body. Under anaerobic conditions, the T3SS machinery remains immature and does not have a needle structure. However, activation of nitrate respiration enhances the completion of the T3SS machinery. Because nitric oxide released by the host inflammatory response increases nitrate concentration, we sought to determine the effect of the inflammatory response on initiation of EHEC microcolony-formation.
Results: The colony-forming capacity was increased in accordance with the increase of nitrate in the medium. The addition of the nitric oxide-producing agent NOR-4 also enhanced the adherence capacity, which was dependent on nitrate reductase encoded by the narGHJI genes. Culture supernatant of epithelial cells, which was stimulated by a cytokine mixture, enhanced the colony-forming capacity of wild-type EHEC but not of the narGHJI mutant. Finally, colony formation by wild-type EHEC on epithelial cells, which were preincubated with heat-killed bacteria, was higher than the narGHJI mutant, and this effect was abolished by aminoguanidine hydrochloride, which is an iNOS (inducible nitric oxide synthase) inhibitor.
Conclusions: These results indicate that the inflammatory response enhances EHEC adherence by increasing nitrate concentration.
Keywords
T3SS, nitric oxide, adherence, colony formation, anaerobic conditions
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
This is a list of supplementary files associated with this preprint. Click to download.
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
Peer Review Timeline
CURRENT STATUS: Published
Version 4
Posted 17 Aug, 2020
Published
On 20 Aug, 2020
No community comments so far
Editorial decision: Accept
On 12 Aug, 2020
Submission checks complete
On 12 Aug, 2020
No comments provided
Editorial decision: Minor revision
On 10 Aug, 2020
No comments provided
Editorial decision: Minor revision
On 04 Aug, 2020
Editor assigned
On 21 Jul, 2020
Submission checks complete
On 20 Jul, 2020
Editor invited
On 20 Jul, 2020
Version (no preprint)
Posted 29 Jul, 2020
Editor assigned
On 06 Aug, 2020
Submission checks complete
On 05 Aug, 2020
Editor invited
On 05 Aug, 2020
This version was not preprinted
No comments provided
Editorial decision: Minor revision
On 10 Jul, 2020
Review #2 received
Received 09 Jul, 2020
Reviewer #2 agreed
On 26 Jun, 2020
Review #1 received
Received 06 Apr, 2020
Reviewer #1 agreed
On 28 Mar, 2020
Reviewers invited
Invitations sent on 27 Mar, 2020
Editor assigned
On 23 Mar, 2020
Submission checks complete
On 20 Mar, 2020
Editor invited
On 19 Mar, 2020
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
Learn more about our company.
This preprint is under consideration at BMC Microbiology. A preprint is a preliminary version of a manuscript that has not completed peer review at a journal. Research Square does not conduct peer review prior to posting preprints. The posting of a preprint on this server should not be interpreted as an endorsement of its validity or suitability for dissemination as established information or for guiding clinical practice.
Learn more about In Review
Research article
Enterohaemorrhagic Escherichia coli activates nitrate respiration to benefit from the inflammatory response for initiation of microcolony-formation
Toru Tobe
Corresponding Author
ORCiD: https://orcid.org/0000-0002-1727-3174
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
Peer Review Timeline
CURRENT STATUS: Published
Version 4
Posted 17 Aug, 2020
Published
On 20 Aug, 2020
No community comments so far
Editorial decision: Accept
On 12 Aug, 2020
Submission checks complete
On 12 Aug, 2020
No comments provided
Editorial decision: Minor revision
On 10 Aug, 2020
No comments provided
Editorial decision: Minor revision
On 04 Aug, 2020
Editor assigned
On 21 Jul, 2020
Submission checks complete
On 20 Jul, 2020
Editor invited
On 20 Jul, 2020
Version (no preprint)
Posted 29 Jul, 2020
Editor assigned
On 06 Aug, 2020
Submission checks complete
On 05 Aug, 2020
Editor invited
On 05 Aug, 2020
This version was not preprinted
No comments provided
Editorial decision: Minor revision
On 10 Jul, 2020
Review #2 received
Received 09 Jul, 2020
Reviewer #2 agreed
On 26 Jun, 2020
Review #1 received
Received 06 Apr, 2020
Reviewer #1 agreed
On 28 Mar, 2020
Reviewers invited
Invitations sent on 27 Mar, 2020
Editor assigned
On 23 Mar, 2020
Submission checks complete
On 20 Mar, 2020
Editor invited
On 19 Mar, 2020
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
License:
This work is licensed under a CC BY 4.0 License. Read Full License
View the published version at BMC Microbiology.
Background: For successful colonization, enterohaemorrhagic Escherichia coli (EHEC) injects virulence factors, called effectors, into target cells through the type three secretion system (T3SS), which is composed of a needle and basal body. Under anaerobic conditions, the T3SS machinery remains immature and does not have a needle structure. However, activation of nitrate respiration enhances the completion of the T3SS machinery. Because nitric oxide released by the host inflammatory response increases nitrate concentration, we sought to determine the effect of the inflammatory response on initiation of EHEC microcolony-formation.
Results: The colony-forming capacity was increased in accordance with the increase of nitrate in the medium. The addition of the nitric oxide-producing agent NOR-4 also enhanced the adherence capacity, which was dependent on nitrate reductase encoded by the narGHJI genes. Culture supernatant of epithelial cells, which was stimulated by a cytokine mixture, enhanced the colony-forming capacity of wild-type EHEC but not of the narGHJI mutant. Finally, colony formation by wild-type EHEC on epithelial cells, which were preincubated with heat-killed bacteria, was higher than the narGHJI mutant, and this effect was abolished by aminoguanidine hydrochloride, which is an iNOS (inducible nitric oxide synthase) inhibitor.
Conclusions: These results indicate that the inflammatory response enhances EHEC adherence by increasing nitrate concentration.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5