title: Characterisation of worldwide Helicobacter pylori strains reveals genetic conservation and essentiality of serine protease HtrA.
abstract: HtrA proteases and chaperones exhibit important roles in periplasmic protein quality control and stress responses. The genetic inactivation of htrA has been described for many bacterial pathogens. However, in some cases such as the gastric pathogen Helicobacter pylori, HtrA is secreted where it cleaves the tumour-suppressor E-cadherin interfering with gastric disease development, but the generation of htrA mutants is still lacking. Here, we show that the htrA gene locus is highly conserved in worldwide strains. HtrA presence was confirmed in 992 H. pylori isolates in gastric biopsy material from infected patients. Differential RNA-sequencing (dRNA-seq) indicated that htrA is encoded in an operon with two subsequent genes, HP1020 and HP1021. Genetic mutagenesis and complementation studies revealed that HP1020 and HP1021, but not htrA, can be mutated. In addition, we demonstrate that suppression of HtrA proteolytic activity with a newly developed inhibitor is sufficient to effectively kill H. pylori, but not other bacteria. We show that Helicobacter htrA is an essential bifunctional gene with crucial intracellular and extracellular functions. Thus, we describe here the first microbe in which htrA is an indispensable gene, a situation unique in the bacterial kingdom. HtrA can therefore be considered a promising new target for anti-bacterial therapy.
authors.affiliation: Lehrstuhl für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, D-91058, Erlangen, Germany.|Institut für Medizinische Mikrobiologie, Otto-von-Guericke Universität Magdeburg, Leipziger Str. 44, D-39120, Magdeburg, Germany.
authors.forename: Nicole
authors.initials: N
authors.lastname: Tegtmeyer
authors.affiliation: Department of Zoology, University of Venda, Private Bag X5050, Thohoyandou, 0950, South Africa.|Konrad-Lorenz-Institut für Vergleichende Verhaltensforschung, Department für Integrative Biologie und Evolution, Veterinärmedizinische Universität Wien, Savoyenstr. 1a, A-1160, Wien, Austria.
authors.forename: Yoshan
authors.initials: Y
authors.lastname: Moodley
authors.affiliation: Michael E. DeBakey Veterans Affairs Medical Center and Baylor College of Medicine, Dept. Medicine-Gastroenterology, Houston, TX, USA.|Oita University Faculty of Medicine, Dept. Environmental and Preventive Medicine, Yufu, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Yamaoka
authors.affiliation: Research Center for Infectious Diseases (ZINF), University of Würzburg, Josef-Schneider-Str. 2/Bau D15, D-97080, Würzburg, Germany.
authors.forename: Sandy Ramona
authors.initials: SR
authors.lastname: Pernitzsch
authors.affiliation: Lehrstuhl für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, D-91058, Erlangen, Germany.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Schmidt
authors.affiliation: Institut für Medizinische Mikrobiologie, Otto-von-Guericke Universität Magdeburg, Leipziger Str. 44, D-39120, Magdeburg, Germany.
authors.forename: Francisco Rivas
authors.initials: FR
authors.lastname: Traverso
authors.affiliation: Department of Molecular Biology, Division of Microbiology, Paris-Lodron University of Salzburg, Billroth Str. 11, A-5020, Salzburg, Austria.
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Schmidt
authors.affiliation: II Medical Department, Klinikum Rechts der Isar, Technical University Munich, Munich, Germany.|German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Rad
authors.affiliation: Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Khay Guan
authors.initials: KG
authors.lastname: Yeoh
authors.affiliation: Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Ho
authors.initials: H
authors.lastname: Bow
authors.affiliation: Unidad de Investigacion en Enfermedades Infecciosas, UMAE Pediatria, IMSS, Mexico City, Mexico.
authors.forename: Javier
authors.initials: J
authors.lastname: Torres
authors.affiliation: Institut für Medizinische Mikrobiologie, Immunologie und Hygiene, Technische Universität München, Munich, 81675, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Gerhard
authors.affiliation: ETH Zürich, Institut für Pharmazeutische Wissenschaften, Vladimir-Prelog-Weg 4, CH-8093, Zürich, Switzerland.
authors.forename: Gisbert
authors.initials: G
authors.lastname: Schneider
authors.affiliation: Department of Molecular Biology, Division of Microbiology, Paris-Lodron University of Salzburg, Billroth Str. 11, A-5020, Salzburg, Austria.
authors.forename: Silja
authors.initials: S
authors.lastname: Wessler
authors.affiliation: Lehrstuhl für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, D-91058, Erlangen, Germany.|Institut für Medizinische Mikrobiologie, Otto-von-Guericke Universität Magdeburg, Leipziger Str. 44, D-39120, Magdeburg, Germany.
authors.forename: Steffen
authors.initials: S
authors.lastname: Backert
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D019143:Evolution, Molecular; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D055786:Gene Knockout Techniques; D005798:Genes, Bacterial; D020043:Genes, Essential; D014644:Genetic Variation; D016480:Helicobacter pylori / Q000201:enzymology* / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D009876:Operon; D019897:Periplasm / Q000235:genetics / Q000378:metabolism; D017423:Sequence Analysis, RNA; D012697:Serine Endopeptidases / Q000235:genetics* / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D015820:Cadherins; D012697:Serine Endopeptidases