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Biology subjects

Woida, P. J.

Publications and source records attributed to Woida, P. J..

3 recordsLinked to original sources

Proximity labeling of the Listeria monocytogenes surface reveals pathogen control of a host deubiquitinase

Intracellular pathogens must navigate the crowded cellular environment to establish infection. Listeria monocytogenes achieves this by recruiting host factors to its surface to hijack the host actin cytoskeleton for motility, form membrane protrusions, and spread from cell to cell. Although these types of Listeria-host interactions are critical for infection, systematic characterization of this interface has been limited. Here, we implement surface display of the promiscuous biotin ligase split-TurboID to profile host proteins recruited to the surface of L. monocytogenes during intracellular infection. This approach identified the host deubiquitinase CYLD as a protein selectively enriched at the pathogen surface. While CYLD promotes infection by suppressing autophagy and innate immunity in macrophages, how L. monocytogenes recruits and appropriates CYLD function in other cell types has remained unclear. We demonstrate that the E3 ligase RNF213 decorates bacterial poles with M1-linked linear ubiquitin, thereby redirecting CYLD to the bacterial surface. We further show ubiquitin is not sufficient to recruit CYLD but requires the L. monocytogenes secreted effector internalin C (InlC). Despite its presence at the bacterial surface, CYLD does not deubiquitinate bacteria or regulate autophagic bacterial clearance in infected epithelial cells. Instead, CYLD and InlC protect L. monocytogenes from IFN-{gamma}- and RNF213-dependent restriction of cell-to-cell spread. Overall, our work profiling the bacterial surface-host interactome has identified a new mechanism by which InlC spatially reprograms CYLD activity, uncoupling its canonical immune functions to promote cell-to-cell spread in epithelial cells. These findings highlight how L. monocytogenes exploits, a host deubiquitinase, to perform cell-type-specific functions during infection.

microbiology↗

An obligate intracellular bacterial pathogen forms a direct, interkingdom membrane contact site

Interorganelle communication regulates cellular homeostasis through the formation of tightly-associated membrane contact sites 1-3. Prior work has identified several ways that intracellular pathogens alter contacts between eukaryotic membranes 4-6, but there is no existing evidence for contact sites spanning eukaryotic and prokaryotic membranes. Here, using a combination of live-cell microscopy and transmission and focused-ion-beam scanning electron microscopy, we demonstrate that the intracellular bacterial pathogen Rickettsia parkeri forms a direct membrane contact site between its bacterial outer membrane and the rough endoplasmic reticulum (ER), with tethers that are approximately 55 nm apart. Depletion of the ER-specific tethers VAPA and VAPB reduced the frequency of rickettsia-ER contacts, suggesting these interactions mimic organelle-ER contacts. Overall, our findings illuminate a direct, interkingdom membrane contact site uniquely mediated by rickettsia that seems to mimic traditional host MCSs.

cell biology↗

Vibrio cholerae MARTX toxin multifunctionality silences inflammatory response to toxin mediated cytoskeletal collapse

AbstractMultifunctional autoprocessing repeats-in-toxin (MARTX) toxins are pore-forming toxins that translocate multiple functionally independent effector domains into a target eukaryotic cell. Vibrio cholerae colonizes intestinal epithelial cells (IECs) and utilizes a MARTX toxin with three effector domains -- an actin cross-linking domain (ACD), a Rho inactivation domain (RID), and an /{beta} hydrolase domain (ABH) -- to suppress innate immunity and enhance colonization. We investigated whether these multiple catalytic enzymes delivered from a single toxin function in a coordinated manner to regulate intestinal innate immunity. Using cultured IECs, we demonstrate that ACD-induced cytoskeletal collapse activated ERK, p38, and JNK mitogen-activated protein kinase (MAPK) signaling to elicit a robust proinflammatory response characterized by production of interleukin-8 (IL-8) and expression of CXCL8, TNF, and other proinflammatory genes. However, RID and ABH, which are naturally delivered along with ACD, blocked MAPK activation via Rac1 and thus prevented the ACD-induced inflammation. RID also abolished IL-8 secretion induced by heat-killed bacteria, tumor necrosis factor, and latrunculin A. Thus, MARTX toxins utilize enzymatic multifunctionality to silence the host response to bacterial factors and to the damage it causes. Further, these data show how V. cholerae MARTX toxin suppresses intestinal inflammation and contributes to cholera being classically defined as non-inflammatory diarrheal disease.

microbiology↗