Cellular Microbiology最新文献

{"title":"BSC2 induces multidrug resistance via contributing to the formation of biofilm in Saccharomyces cerevisiae","authors":"Zhiwei Huang,&nbsp;Hongsheng Dai,&nbsp;Xiaoyu Zhang,&nbsp;Qiao Wang,&nbsp;Jing Sun,&nbsp;Yunxia Deng,&nbsp;Ping Shi","doi":"10.1111/cmi.13391","DOIUrl":"10.1111/cmi.13391","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p>Biofilm plays an important role in fungal multidrug resistance (MDR). Our previous studies showed that <i>BSC2</i> is involved in resistance to amphotericin B (AMB) through antioxidation in <i>Saccharomyces cerevisiae</i>. In this study, the overexpression of <i>BSC2</i> and <i>IRC23</i> induced strong MDR in <i>S. cerevisiae</i>. <i>BSC2</i>-overexpression affected cellular flocculation, cell surface hydrophobicity, biofilm formation and invasive growth. However, it failed to induce caspofungin (CAS) resistance and affect the invasive growth in <i>FLO</i> mutant strains (<i>FLO11</i>Δ, <i>FLO1</i>Δ, <i>FLO8</i>Δ and <i>TUP1</i>Δ). Furthermore, the overexpression of <i>BSC2</i> compensated for chitin synthesis defects to maintain the cell wall integrity and significantly reduced the cell morphology abnormality induced by CAS. However, it could not repair the cell wall damage caused by CAS in the <i>FLO</i> mutant strains. Although <i>BSC2</i> overexpression increased the level of mannose in the cell wall, <i>DPM1</i> overexpression in both BY4741 and <i>bsc2</i>∆ could confer resistance to CAS and AMB. In addition, <i>BSC2</i> overexpression significantly increased the mRNA expression of <i>FLO11</i>, <i>FLO1</i>, <i>FLO8</i> and <i>TUP1</i>. <i>BSC2</i> may function as a regulator of <i>FLO</i> genes and be involved in cell wall integrity in yeast. Taken together, our data demonstrate that <i>BSC2</i> induces MDR in a <i>FLO</i> pathway-dependent manner via contributing to the formation of biofilms in <i>S. cerevisiae</i>.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Take Aways</h3>\u0000 \u0000 <div>\u0000 <ul>\u0000 \u0000 <li>Overexpression of <i>BSC2</i> induced strong MDR in <i>S. cerevisiae</i>.</li>\u0000 \u0000 <li><i>BSC2</i> affected cellular flocculation, CSH, biofilm formation and invasive growth.</li>\u0000 \u0000 <li><i>BSC2</i> could not repair the cell wall damage caused by CAS in the <i>FLO</i> mutants.</li>\u0000 \u0000 <li><i>BSC2</i> may function as a regulator of <i>FLO</i> genes to maintain cell wall integrity.</li>\u0000 \u0000 <li><i>BSC2</i> promotes biofilm formation in a <i>FLO</i> pathway-dependent manner to induce MDR.</li>\u0000 </ul>\u0000 </div>\u0000 </section>\u0000 </div>","PeriodicalId":9844,"journal":{"name":"Cellular Microbiology","volume":"23 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2021-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/cmi.13391","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39384095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rickettsia conorii survival in THP-1 macrophages involves host lipid droplet alterations and active rickettsial protein production","authors":"Paige E. Allen,&nbsp;Robert C. Noland,&nbsp;Juan J. Martinez","doi":"10.1111/cmi.13390","DOIUrl":"10.1111/cmi.13390","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;p&gt;&lt;i&gt;Rickettsia conorii&lt;/i&gt; is a Gram-negative, cytosolic intracellular bacterium that has classically been investigated in terms of endothelial cell infection. However, &lt;i&gt;R. conorii&lt;/i&gt; and other human pathogenic &lt;i&gt;Rickettsia&lt;/i&gt; species have evolved mechanisms to grow in various cell types, including macrophages, during mammalian infection. During infection of these phagocytes, &lt;i&gt;R. conorii&lt;/i&gt; shifts the host cell's overall metabolism towards an anti-inflammatory M2 response, metabolically defined by an increase in host lipid metabolism and oxidative phosphorylation. Lipid metabolism has more recently been identified as a key regulator of host homeostasis through modulation of immune signalling and metabolism. Intracellular pathogens have adapted mechanisms of hijacking host metabolic pathways including host lipid catabolic pathways for various functions required for growth and survival. In the present study, we hypothesised that alterations of host lipid droplets initiated by lipid catabolic pathways during &lt;i&gt;R. conorii&lt;/i&gt; infection is important for bacterial survival in macrophages. Herein, we determined that host lipid droplet modulation is initiated early during &lt;i&gt;R. conorii&lt;/i&gt; infection, and these alterations rely on active bacteria and lipid catabolic pathways. We also find that these lipid catabolic pathways are essential for efficient bacterial survival. Unlike the mechanisms used by other intracellular pathogens, the catabolism of lipid droplets induced by &lt;i&gt;R. conorii&lt;/i&gt; infection is independent of upstream host peroxisome proliferator-activated receptor-alpha (PPARα) signalling. Inhibition of PPARɣ signalling and lipid droplet accumulation in host cells cause a significant decrease in &lt;i&gt;R. conorii&lt;/i&gt; survival suggesting a negative correlation with lipid droplet production and &lt;i&gt;R. conorii&lt;/i&gt; survival. Together, these results strongly suggest that the modulation of lipid droplets in macrophage cells infected by &lt;i&gt;R. conorii&lt;/i&gt; is an important and underappreciated aspect of the infection process.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Take Aways&lt;/h3&gt;\u0000 \u0000 &lt;div&gt;\u0000 &lt;ul&gt;\u0000 \u0000 &lt;li&gt;Host lipid droplets are differentially altered in early and replicative stages of THP-1 macrophage infection with &lt;i&gt;R. conorii&lt;/i&gt;.&lt;/li&gt;\u0000 \u0000 &lt;li&gt;Lipid droplet alterations are initiated in a bacterial-dependent manner and do not require host peroxisome proliferator-activated receptors α or ɣ activation.&lt;/li&gt;\u0000 \u0000 &lt;li&gt;Pharmacological inhibition of host lipid catabolic processes during &lt;i&gt;R. conorii&lt;/i&gt; infection indicates a requirement of lipid catabolism for bacterial survival and initiation of lipid droplet modulation.&lt;/li&gt;\u0000 \u0000 ","PeriodicalId":9844,"journal":{"name":"Cellular Microbiology","volume":"23 11","pages":""},"PeriodicalIF":3.4,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/cmi.13390","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39369562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The fungivorous amoeba Protostelium aurantium targets redox homeostasis and cell wall integrity during intracellular killing of Candida parapsilosis","authors":"Silvia Radosa,&nbsp;Jakob L. Sprague,&nbsp;Siu-Hin Lau,&nbsp;Renáta Tóth,&nbsp;Jörg Linde,&nbsp;Thomas Krüger,&nbsp;Marcel Sprenger,&nbsp;Lydia Kasper,&nbsp;Martin Westermann,&nbsp;Olaf Kniemeyer,&nbsp;Bernhard Hube,&nbsp;Axel A. Brakhage,&nbsp;Attila Gácser,&nbsp;Falk Hillmann","doi":"10.1111/cmi.13389","DOIUrl":"10.1111/cmi.13389","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p>Predatory interactions among microbes are major evolutionary driving forces for biodiversity. The fungivorous amoeba <i>Protostelium aurantium</i> has a wide fungal food spectrum including foremost pathogenic members of the genus <i>Candida</i>. Here we show that upon phagocytic ingestion by the amoeba, <i>Candida parapsilosis</i> is confronted with an oxidative burst and undergoes lysis within minutes of processing in acidified phagolysosomes. On the fungal side, a functional genomic approach identified copper and redox homeostasis as primary targets of amoeba predation, with the highly expressed copper exporter gene <i>CRP1</i> and the peroxiredoxin gene <i>PRX1</i> contributing to survival when encountered with <i>P. aurantium</i>. The fungicidal activity was largely retained in intracellular vesicles of the amoebae. Following their isolation, the content of these vesicles induced immediate killing and lysis of <i>C. parapsilosis</i> in vitro. Proteomic analysis identified 56 vesicular proteins from <i>P. aurantium</i>. Although completely unknown proteins were dominant, many of them could be categorised as hydrolytic enzymes targeting the fungal cell wall, indicating that fungal cell wall structures are under selection pressure by predatory phagocytes in natural environments.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Take Away</h3>\u0000 \u0000 <div>\u0000 <ul>\u0000 \u0000 <li>The amoeba <i>Protostelium aurantium</i> feeds on fungi, such as <i>Candida parapsilosis</i>.</li>\u0000 \u0000 <li>Ingested yeast cells are exposed to reactive oxygen species.</li>\u0000 \u0000 <li>A copper exporter and a peroxiredoxin contribute to fungal defence.</li>\u0000 \u0000 <li>Yeast cells undergo intracellular lysis.</li>\u0000 \u0000 <li>Lysis occurs via a cocktail of hydrolytic enzymes from intracellular vesicles.</li>\u0000 </ul>\u0000 </div>\u0000 </section>\u0000 </div>","PeriodicalId":9844,"journal":{"name":"Cellular Microbiology","volume":"23 11","pages":""},"PeriodicalIF":3.4,"publicationDate":"2021-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/cmi.13389","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39382953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Porphyromonas gingivalis induces penetration of lipopolysaccharide and peptidoglycan through the gingival epithelium via degradation of coxsackievirus and adenovirus receptor","authors":"Hiroki Takeuchi,&nbsp;Shunsuke Yamaga,&nbsp;Naoko Sasaki,&nbsp;Masae Kuboniwa,&nbsp;Michiya Matsusaki,&nbsp;Atsuo Amano","doi":"10.1111/cmi.13388","DOIUrl":"10.1111/cmi.13388","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p><i>Porphyromonas gingivalis</i> is a major pathogen of human periodontitis and dysregulates innate immunity at the gingival epithelial surface. We previously reported that the bacterium specifically degrades junctional adhesion molecule 1 (JAM1), causing gingival epithelial barrier breakdown. However, the functions of other JAM family protein(s) in epithelial barrier dysregulation caused by <i>P. gingivalis</i> are not fully understood. The present results show that gingipains, Arg-specific or Lys-specific cysteine proteases produced by <i>P. gingivalis</i>, specifically degrade coxsackievirus and adenovirus receptor (CXADR), a JAM family protein, at R145 and K235 in gingival epithelial cells. In contrast, a gingipain-deficient <i>P. gingivalis</i> strain was found to be impaired in regard to degradation of CXADR. Furthermore, knockdown of CXADR in artificial gingival epithelium increased permeability to dextran 40 kDa, lipopolysaccharide and peptidoglycan, whereas overexpression of CXADR in a gingival epithelial tissue model prevented penetration by those agents following <i>P. gingivalis</i> infection. Together, these results suggest that <i>P. gingivalis</i> gingipains breach the stratified squamous epithelium barrier by degrading CXADR as well as JAM1, which allows for efficient transfer of bacterial virulence factors into subepithelial tissues.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Takeaways</h3>\u0000 \u0000 <div>\u0000 <ul>\u0000 \u0000 <li><i>P. gingivalis</i>, a periodontal pathogen, degraded coxsackievirus and adenovirus receptor (CXADR), a JAM family protein, in gingival epithelial tissues.</li>\u0000 \u0000 <li><i>P. gingivalis</i> gingipains, cysteine proteases, degraded CXADR at R145 and K235.</li>\u0000 \u0000 <li>CXADR degradation by <i>P. gingivalis</i> caused increased permeability to lipopolysaccharide and peptidoglycan through gingival epithelial tissues.</li>\u0000 </ul>\u0000 </div>\u0000 </section>\u0000 </div>","PeriodicalId":9844,"journal":{"name":"Cellular Microbiology","volume":"23 11","pages":""},"PeriodicalIF":3.4,"publicationDate":"2021-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/cmi.13388","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39359460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Zinc finger proteins of Plasmodium falciparum","authors":"Che Julius Ngwa,&nbsp;Afia Farrukh,&nbsp;Gabriele Pradel","doi":"10.1111/cmi.13387","DOIUrl":"10.1111/cmi.13387","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p>Zinc finger proteins (ZFPs) are a large diverse family of proteins with one or more zinc finger domains in which zinc is important in stabilising the domain. ZFPs can interact with DNA, RNA, lipids or even other proteins and therefore contribute to diverse cellular processes including transcriptional regulation, ubiquitin-mediated protein degradation, mRNA decay and stability. In this review, we provide the first comprehensive classification of ZFPs of the malaria parasite <i>Plasmodium falciparum</i> and provide a state of knowledge on the main ZFPs in the parasite, which include the C2H2, CCCH, RING finger and the PHD finger proteins.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Take aways</h3>\u0000 \u0000 <div>\u0000 <ul>\u0000 \u0000 <li>The <i>Plasmodium falciparum</i> genome encodes 170 putative Zinc finger proteins (ZFPs).</li>\u0000 \u0000 <li>The C2H2, CCCH, RING finger and PHD finger subfamilies of ZFPs are most represented.</li>\u0000 \u0000 <li>Known ZFP functions include the regulation of mRNA metabolism and proteostasis.</li>\u0000 </ul>\u0000 </div>\u0000 </section>\u0000 </div>","PeriodicalId":9844,"journal":{"name":"Cellular Microbiology","volume":"23 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2021-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/cmi.13387","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39331456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Microbiology: A New Vision and Expanded Scope.","authors":"M. Ostankovitch, T. Soldati, J. Helmann","doi":"10.1111/cmi.13386","DOIUrl":"https://doi.org/10.1111/cmi.13386","url":null,"abstract":"","PeriodicalId":9844,"journal":{"name":"Cellular Microbiology","volume":"1 1","pages":"e13386"},"PeriodicalIF":3.4,"publicationDate":"2021-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/cmi.13386","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45285275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cover Image: Disassembly of the apical junctional complex during the transmigration of Leptospira interrogans across polarized renal proximal tubule epithelial cells (Cellular Microbiology 09/2021)","authors":"Isabel Sebastián,&nbsp;Nobuhiko Okura,&nbsp;Bruno M. Humbel,&nbsp;Jun Xu,&nbsp;Idam Hermawan,&nbsp;Chiaki Matsuura,&nbsp;Malgorzata Hall,&nbsp;Chitoshi Takayama,&nbsp;Tetsu Yamashiro,&nbsp;Shuichi Nakamura,&nbsp;Claudia Toma","doi":"10.1111/cmi.13382","DOIUrl":"10.1111/cmi.13382","url":null,"abstract":"<p>Focused ion beam-scanning electron microscopy image of renal proximal tubule epithelial cells infected for 24 hrs with <i>Leptospira interrogans</i>. Leptospires localized in the gap between two adjacent cells (red and blue). For further details, readers are referred to the article by Sebastián et al. on p. e13343 of this issue.\u0000\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":9844,"journal":{"name":"Cellular Microbiology","volume":"23 9","pages":""},"PeriodicalIF":3.4,"publicationDate":"2021-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/cmi.13382","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45395980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Host cell membrane microdomains and fungal infection","authors":"Taiane N. Souza,&nbsp;Alessandro F. Valdez,&nbsp;Juliana Rizzo,&nbsp;Daniel Zamith-Miranda,&nbsp;Allan Jefferson Guimarães,&nbsp;Joshua D. Nosanchuk,&nbsp;Leonardo Nimrichter","doi":"10.1111/cmi.13385","DOIUrl":"10.1111/cmi.13385","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p>Lipid microdomains or lipid rafts are dynamic and tightly ordered regions of the plasma membrane. In mammalian cells, they are enriched in cholesterol, glycosphingolipids, Glycosylphosphatidylinositol-anchored and signalling-related proteins. Several studies have suggested that mammalian pattern recognition receptors are concentrated or recruited to lipid domains during host-pathogen association to enhance the effectiveness of host effector processes. However, pathogens have also evolved strategies to exploit these domains to invade cells and survive. In fungal organisms, a complex cell wall network usually mediates the first contact with the host cells. This cell wall may contain virulence factors that interfere with the host membrane microdomains dynamics, potentially impacting the infection outcome. Indeed, the microdomain disruption can dampen fungus-host cell adhesion, phagocytosis and cellular immune responses. Here, we provide an overview of regulatory strategies employed by pathogenic fungi to engage with and potentially subvert the lipid microdomains of host cells.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Take Away</h3>\u0000 \u0000 <div>\u0000 <ul>\u0000 \u0000 <li>Lipid microdomains are ordered regions of the plasma membrane enriched in cholesterol, glycosphingolipids (GSL), GPI-anchored and signalling-related proteins.</li>\u0000 \u0000 <li>Pathogen recognition by host immune cells can involve lipid microdomain participation. During this process, these domains can coalesce in larger complexes recruiting receptors and signalling proteins, significantly increasing their signalling abilities.</li>\u0000 \u0000 <li>The antifungal innate immune response is mediated by the engagement of pathogen-associated molecular patterns to pattern recognition receptors (PRRs) at the plasma membrane of innate immune cells. Lipid microdomains can concentrate or recruit PRRs during host cell-fungi association through a multi-interactive mechanism. This association can enhance the effectiveness of host effector processes. However, virulence factors at the fungal cell surface and extracellular vesicles can re-assembly these domains, compromising the downstream signalling and favouring the disease development.</li>\u0000 \u0000 <li>Lipid microdomains are therefore very attractive targets for novel drugs to combat fungal infections.</li>\u0000 </ul>\u0000 </div>\u0000 </section>\u0000 </div>","PeriodicalId":9844,"journal":{"name":"Cellular Microbiology","volume":"23 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2021-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/cmi.13385","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39311100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Host manipulation by bacterial type III and type IV secretion system effector proteases","authors":"Flávia Viana,&nbsp;Shruthi Sachidanandan Peringathara,&nbsp;Arshad Rizvi,&nbsp;Gunnar N. Schroeder","doi":"10.1111/cmi.13384","DOIUrl":"10.1111/cmi.13384","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p>Proteases are powerful enzymes, which cleave peptide bonds, leading most of the time to irreversible fragmentation or degradation of their substrates. Therefore they control many critical cell fate decisions in eukaryotes. Bacterial pathogens exploit this power and deliver protease effectors through specialised secretion systems into host cells. Research over the past years revealed that the functions of protease effectors during infection are diverse, reflecting the lifestyles and adaptations to specific hosts; however, only a small number of peptidase families seem to have given rise to most of these protease virulence factors by the evolution of different substrate-binding specificities, intracellular activation and subcellular targeting mechanisms. Here, we review our current knowledge about the enzymology and function of protease effectors, which Gram-negative bacterial pathogens translocate via type III and IV secretion systems to irreversibly manipulate host processes. We highlight emerging concepts such as signalling by protease cleavage products and effector-triggered immunity, which host cells employ to detect and defend themselves against a protease attack.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Take Away</h3>\u0000 \u0000 <div>\u0000 <ul>\u0000 \u0000 <li>Proteases irreversibly cleave proteins to control critical cell fate decisions.</li>\u0000 \u0000 <li>Gram-negative bacteria use type III and IV secretion systems to inject effectors.</li>\u0000 \u0000 <li>Protease effectors are integral weapons for the manipulation of host processes.</li>\u0000 \u0000 <li>Effectors evolved from few peptidase families to target diverse substrates.</li>\u0000 \u0000 <li>Effector-triggered immunity upon proteolytic attack emerges as host defence.</li>\u0000 </ul>\u0000 </div>\u0000 </section>\u0000 </div>","PeriodicalId":9844,"journal":{"name":"Cellular Microbiology","volume":"23 11","pages":""},"PeriodicalIF":3.4,"publicationDate":"2021-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/cmi.13384","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39311101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mucosal immune responses in the trachea after chronic infection with Mycoplasma gallisepticum in unvaccinated and vaccinated mature chickens","authors":"Sathya N. Kulappu Arachchige,&nbsp;Nadeeka K. Wawegama,&nbsp;Mauricio J. C. Coppo,&nbsp;Habtamu B. Derseh,&nbsp;Paola K. Vaz,&nbsp;Anna Kanci Condello,&nbsp;Oluwadamilola S. Omotainse,&nbsp;Amir H. Noormohammadi,&nbsp;Glenn F. Browning","doi":"10.1111/cmi.13383","DOIUrl":"10.1111/cmi.13383","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;p&gt;Tracheitis associated with the chronic respiratory disease in chickens caused by &lt;i&gt;Mycoplasma gallisepticum&lt;/i&gt; is marked by infiltration of leukocytes into the mucosa. Although cytokines/chemokines are known to play a key role in the recruitment, differentiation, and proliferation of leukocytes, those that are produced and secreted into the trachea during the chronic stages of infection with &lt;i&gt;M. gallisepticum&lt;/i&gt; have not been described previously. In this study, the levels of transcription in the trachea of genes encoding a panel of 13 cytokines/chemokines were quantified after experimental infection with the &lt;i&gt;M. gallisepticum&lt;/i&gt; wild-type strain Ap3AS in unvaccinated chickens and chickens vaccinated 40-, 48- or 57-weeks previously with the novel attenuated strain ts-304. These transcriptional levels in unvaccinated/infected and vaccinated/infected chickens were compared with those of unvaccinated/uninfected and vaccinated/uninfected chickens. Pathological changes and subsets of leukocytes infiltrating the tracheal mucosa were concurrently assessed by histopathological examination and indirect immunofluorescent staining. After infection, unvaccinated birds had a significant increase in tracheal mucosal thickness and in transcription of genes for cytokines/chemokines, including those for IFN-γ, IL-17, RANTES (CCLi4), and CXCL-14, and significant downregulation of IL-2 gene transcription. B cells, CD3&lt;sup&gt;+&lt;/sup&gt; or CD4&lt;sup&gt;+&lt;/sup&gt; cells and macrophages (KUL01&lt;sup&gt;+&lt;/sup&gt;) accumulated in the mucosa but CD8&lt;sup&gt;+&lt;/sup&gt; cells were not detected. In vaccinated birds, the levels of transcription of the genes for IL-6, IL-2, RANTES and CXCL-14 were significantly lower after infection than in the unvaccinated/infected and/or unvaccinated/uninfected birds, while the transcription of the IFN-γ gene was significantly upregulated, and there were aggregations of B cells in the tracheal mucosa. These observations indicated that &lt;i&gt;M. gallisepticum&lt;/i&gt; may have suppressed Th2 responses by upregulating secretion of IFN-γ and IL-17 by CD4&lt;sup&gt;+&lt;/sup&gt; cells and induced immune dysregulation characterized by depletion of CD8&lt;sup&gt;+&lt;/sup&gt; cells and downregulation of IL-2 in the tracheas of unvaccinated birds. The ts-304 vaccine appeared to induce long-term protection against this immune dysregulation.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Take Away&lt;/h3&gt;\u0000 \u0000 &lt;div&gt;\u0000 &lt;ul&gt;\u0000 \u0000 &lt;li&gt;The ts-304 vaccine-induced long-term protection against immune dysregulation caused by &lt;i&gt;M. gallisepticum&lt;/i&gt;&lt;/li&gt;\u0000 \u0000 &lt;li&gt;Detection of B cells and plasma cells in the tracheal mucosa suggested that long-term protection is mediated by mucosal B cell memory&lt;/li&gt;\u0000 \u0000 &lt;li&gt;Infection of","PeriodicalId":9844,"journal":{"name":"Cellular Microbiology","volume":"23 11","pages":""},"PeriodicalIF":3.4,"publicationDate":"2021-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/cmi.13383","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39271613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}