scholarly journals The Campylobacter jejuni CiaD effector co-opts the host cell protein IQGAP1 to promote cell entry

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Nicholas M. Negretti ◽  
Christopher R. Gourley ◽  
Prabhat K. Talukdar ◽  
Geremy Clair ◽  
Courtney M. Klappenbach ◽  
...  

AbstractCampylobacter jejuni is a foodborne pathogen that binds to and invades the epithelial cells lining the human intestinal tract. Maximal invasion of host cells by C. jejuni requires cell binding as well as delivery of the Cia proteins (Campylobacter invasion antigens) to the host cell cytosol via the flagellum. Here, we show that CiaD binds to the host cell protein IQGAP1 (a Ras GTPase-activating-like protein), thus displacing RacGAP1 from the IQGAP1 complex. This, in turn, leads to the unconstrained activity of the small GTPase Rac1, which is known to have roles in actin reorganization and internalization of C. jejuni. Our results represent the identification of a host cell protein targeted by a flagellar secreted effector protein and demonstrate that C. jejuni-stimulated Rac signaling is dependent on IQGAP1.

2020 ◽  
Vol 8 (3) ◽  
pp. 389 ◽  
Author(s):  
Prabhat K. Talukdar ◽  
Nicholas M. Negretti ◽  
Kyrah L. Turner ◽  
Michael E. Konkel

Campylobacter jejuni, a zoonotic pathogen that frequently colonizes poultry, possesses two Microbial Surface Components Recognizing Adhesive Matrix Molecule(s) (MSCRAMMs) termed CadF and FlpA that bind to the glycoprotein fibronectin (FN). Previous to this study, it was not known whether the CadF and FlpA proteins were functionally redundant or if both were required to potentiate host cell binding and signaling processes. We addressed these questions by generating a complete repertoire of cadF and flpA mutants and complemented isolates, and performing multiple phenotypic assays. Both CadF and FlpA were found to be necessary for the maximal binding of C. jejuni to FN and to host cells. In addition, both CadF and FlpA are required for the delivery of the C. jejuni Cia effector proteins into the cytosol of host target cells, which in turn activates the MAPK signaling pathway (Erk 1/2) that is required for the C. jejuni invasion of host cells. These data demonstrate the non-redundant and bi-functional nature of these two C. jejuni FN-binding proteins. Taken together, the C. jejuni CadF and FlpA adhesins facilitate the binding of C. jejuni to the host cells, permit delivery of effector proteins into the cytosol of a host target cell, and aid in the rewiring of host cell signaling pathways to alter host cell behavior.


Parasitology ◽  
2006 ◽  
Vol 134 (4) ◽  
pp. 491-502 ◽  
Author(s):  
M. L. BELAUNZARÁN ◽  
M. J. WAINSZELBAUM ◽  
E. M. LAMMEL ◽  
G. GIMENEZ ◽  
M. M. ALOISE ◽  
...  

Here we have studied phospholipase A1 (Plase A1) from Trypanosoma cruzi infective stages and it's possible role regarding the interaction with mammalian host cells. Plase A1 was mainly detected as a membrane-bound activity in the infective amastigote and trypomastigote stages, being remarkably higher with respect to the non-infective epimastigotes. It is noteworthy that only the infective stages secreted Plase A1. Moreover, along the differentiation process from epimastigotes into metacyclic trypomastigotes, the secreted enzyme activity increased simultaneously with the appearance of metacyclic forms, as expected. Since this enzyme is predominantly membrane-associated and secreted by the infective stages, Vero cell lipid profile modifications were analysed after interaction with either intact infective parasites or purified T. cruzi Plase A1. Significant changes in Vero cell lipid composition were observed, with the appearance of free fatty acids, diacylglycerol and lysophosphatidylcholine. Concomitantly with the generation of second lipid messengers, host cell protein kinase C activation was demonstrated. These results indicate that T. cruzi Plase A1 could play a critical role in the early events of parasite-host cell interaction that precede invasion.


2016 ◽  
Vol 18 (6) ◽  
pp. 1439-1452 ◽  
Author(s):  
Vibha Jawa ◽  
Marisa K. Joubert ◽  
Qingchun Zhang ◽  
Meghana Deshpande ◽  
Suminda Hapuarachchi ◽  
...  

2015 ◽  
Vol 9 (S9) ◽  
Author(s):  
Nadine Kochanowski ◽  
Gaetan Siriez ◽  
Larissa Mukankurayija ◽  
Aurélie Delangle ◽  
Alex Murray-Smith ◽  
...  

mBio ◽  
2021 ◽  
Author(s):  
Courtney M. Klappenbach ◽  
Nicholas M. Negretti ◽  
Jesse Aaron ◽  
Teng-Leong Chew ◽  
Michael E. Konkel

Campylobacter jejuni is a major foodborne pathogen that causes severe gastritis. We investigated the dynamics of focal adhesion structure and function in C. jejuni -infected epithelial cells.


Biologicals ◽  
2018 ◽  
Vol 52 ◽  
pp. 59-66 ◽  
Author(s):  
Sabine Johnson ◽  
Jun X. Wheeler ◽  
Robin Thorpe ◽  
Mary Collins ◽  
Yasuhiro Takeuchi ◽  
...  

2014 ◽  
Vol 2 (4) ◽  
pp. 464-477
Author(s):  
Zilun Shi ◽  
Chris Dawson ◽  
Stephen L.W. On ◽  
Malik Altaf Hussain

A proteome map of the foodborne pathogen Campylobacter jejuni NCTC11168 was analyzed using a state-of-the-art gel-free proteomic approach for the first time. A whole cell protein extract was prepared from the C. jejuni strain NCTC11168 grown in brain heart infusion (BHI) broth at 42°C under microaerobic conditions. A gel-free technique using isobaric tags for relative and absolute quantitation (iTRAQ) was employed to create a protein expression profile of the strain. Liquid chromatography-mass spectrometry (LC-MS/MS) was used to identify the proteins. Protein functionalities were searched to classify them. A total of 235 proteins were identified in the whole cell protein fraction of C. jejuni NCTC11168 cells using iTRAQ analysis. Functional grouping of the identified proteins showed that forty percent of these proteins were associated with energy metabolism, protein synthesis and genetic information processing. iTRAQ was faster, easier and proved more sensitive than two-dimensional gel-based proteomics approaches previously applied to C. jejuni, making it an attractive tool for further studies of cellular physiological response. DOI: http://dx.doi.org/10.3126/ijasbt.v2i4.11253  Int J Appl Sci Biotechnol, Vol. 2(4): 464-477 


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