TY  - JOUR
A1  - Tegtmeyer, Nicole
A1  - Moodley, Yoshan
A1  - Yamaoka, Yoshio
A1  - Pernitzsch, Sandy Ramona
A1  - Schmidt, Vanessa
A1  - Traverso, Francisco Rivas
A1  - Schmidt, Thomas P.
A1  - Rad, Roland
A1  - Yeoh, Khay Guan
A1  - Bow, Ho
A1  - Torres, Javier
A1  - Gerhard, Markus
A1  - Schneider, Gisbert
A1  - Wessler, Silja
A1  - Backert, Steffen
T1  - Characterisation of worldwide Helicobacter pylori strains reveals genetic conservation and essentiality of serine protease HtrA
JF  - Molecular Microbiology
N2  - 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.
KW  - Helicobacter pylori
KW  - cag pathogenicity island
KW  - Differential RNA-sequencing
KW  - epithelial cells
KW  - campylobacter jejuni infection
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-190774
VL  - 99
IS  - 5
ER  - 
TY  - JOUR
A1  - Trujillo‐Viera, Jonathan
A1  - El‐Merahbi, Rabih
A1  - Schmidt, Vanessa
A1  - Karwen, Till
A1  - Loza‐Valdes, Angel
A1  - Strohmeyer, Akim
A1  - Reuter, Saskia
A1  - Noh, Minhee
A1  - Wit, Magdalena
A1  - Hawro, Izabela
A1  - Mocek, Sabine
A1  - Fey, Christina
A1  - Mayer, Alexander E.
A1  - Löffler, Mona C.
A1  - Wilhelmi, Ilka
A1  - Metzger, Marco
A1  - Ishikawa, Eri
A1  - Yamasaki, Sho
A1  - Rau, Monika
A1  - Geier, Andreas
A1  - Hankir, Mohammed
A1  - Seyfried, Florian
A1  - Klingenspor, Martin
A1  - Sumara, Grzegorz
T1  - Protein Kinase D2 drives chylomicron‐mediated lipid transport in the intestine and promotes obesity
JF  - EMBO Molecular Medicine
N2  - Lipids are the most energy‐dense components of the diet, and their overconsumption promotes obesity and diabetes. Dietary fat content has been linked to the lipid processing activity by the intestine and its overall capacity to absorb triglycerides (TG). However, the signaling cascades driving intestinal lipid absorption in response to elevated dietary fat are largely unknown. Here, we describe an unexpected role of the protein kinase D2 (PKD2) in lipid homeostasis. We demonstrate that PKD2 activity promotes chylomicron‐mediated TG transfer in enterocytes. PKD2 increases chylomicron size to enhance the TG secretion on the basolateral side of the mouse and human enterocytes, which is associated with decreased abundance of APOA4. PKD2 activation in intestine also correlates positively with circulating TG in obese human patients. Importantly, deletion, inactivation, or inhibition of PKD2 ameliorates high‐fat diet‐induced obesity and diabetes and improves gut microbiota profile in mice. Taken together, our findings suggest that PKD2 represents a key signaling node promoting dietary fat absorption and may serve as an attractive target for the treatment of obesity.
KW  - chylomicron
KW  - fat absorption
KW  - intestine
KW  - obesity
KW  - protein kinase D2/PKD2/PRKD2
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239018
VL  - 13
IS  - 5
ER  -