Properties of the HtrA protease from bacterium Helicobacter pylori whose activity is indispensable for growth under stress conditions

Urszula Zarzecka , Anna Modrak-Wójcik , Donata Figaj , Małgorzata Apanowicz , Adam Lesner , Agnieszka Bzowska , Barbara Lipińska , Anna Zawilak-Pawlik , Steffen Backert , Joanna Skórko-Glonek


The protease high temperature requirement A from the gastric pathogen Helicobacter pylori (HtrAHp) belongs to the well conserved family of serine proteases. HtrAHp is an important secreted virulence factor involved in the disruption of tight and adherens junctions during infection. Very little is known about the function of HtrAHp in the H. pylori cell physiology due to the lack of htrA knockout strains. Here, using a newly constructed 1htrA mutant strain, we found that bacteria deprived of HtrAHp showed increased sensitivity to certain types of stress, including elevated temperature, pH and osmotic shock, as well as treatment with puromycin. These data indicate that HtrAHp plays a protective role in the H. pylori cell, presumably associated with maintenance of important periplasmic and outer membrane proteins. Purified HtrAHp was shown to be very tolerant to a wide range of temperature and pH values. Remarkably, the protein exhibited a very high thermal stability with the melting point (Tm) values of above 85∘C. Moreover, HtrAHp showed the capability to regain its active structure following treatment under denaturing conditions. Taken together, our work demonstrates that HtrAHp is well adapted to operate under harsh conditions as an exported virulence factor, but also inside the bacterial cell as an important component of the protein quality control system in the stressed cellular envelope.
Author Urszula Zarzecka (FB / DB)
Urszula Zarzecka,,
- Department of Biochemistry
, Anna Modrak-Wójcik - [Uniwersytet Warszawski]
Anna Modrak-Wójcik,,
, Donata Figaj (FB / DB)
Donata Figaj,,
- Department of Biochemistry
, Małgorzata Apanowicz (FB / DB)
Małgorzata Apanowicz,,
- Department of Biochemistry
, Adam Lesner (FCh / DET / LBAN)
Adam Lesner,,
- Laboratory of Biochemical Analytics and Nanodiagnostics
, Agnieszka Bzowska - [Uniwersytet Warszawski]
Agnieszka Bzowska,,
, Barbara Lipińska (FB / DB)
Barbara Lipińska,,
- Department of Biochemistry
, Anna Zawilak-Pawlik - [Ludwik Hirszfeld Institute of Immunology and Experimental Therapy of the Polish Academy of Sciences]
Anna Zawilak-Pawlik,,
, Steffen Backert - [Friedrich-Alexander-Universität Erlangen-Nürnberg]
Steffen Backert,,
, Joanna Skórko-Glonek (FB / DB)
Joanna Skórko-Glonek,,
- Department of Biochemistry
Journal seriesFrontiers in Microbiology, ISSN 1664-302X, (N/A 100 pkt)
Issue year2019
Publication size in sheets0.75
Keywords in EnglishHtrA, Helicobacter pylori, virulent factor, proteolytic activity, protein quality control system, stress endurance, oligomerization
ASJC Classification2726 Microbiology (medical); 2404 Microbiology
Languageen angielski
LicenseJournal (articles only); published final; Uznanie Autorstwa (CC-BY); with publication
Score (nominal)100
Score sourcejournalList
ScoreMinisterial score = 100.0, 12-12-2019, ArticleFromJournal
Publication indicators WoS Citations = 0; Scopus Citations = 1; Scopus SNIP (Source Normalised Impact per Paper): 2018 = 1.227; WoS Impact Factor: 2018 = 4.259 (2) - 2018=4.84 (5)
Citation count*1 (2019-12-09)
Share Share

Get link to the record

* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.
Are you sure?