Cell Surface最新文献

{"title":"Temperature-dependent regulation of bacterial cell division hydrolases by the coordinated action of a regulatory RNA and the ClpXP protease","authors":"Viktor H. Mebus ,&nbsp;Larissa M. Busch ,&nbsp;Morten Børre ,&nbsp;Tobias K. Nielsen ,&nbsp;Martin Saxtorph Bojer ,&nbsp;Camilla Henriksen ,&nbsp;Maria D. Barbuti ,&nbsp;Danae M. Angeles ,&nbsp;Kamilla Brejndal ,&nbsp;Stephan Michalik ,&nbsp;Manuela Gesell Salazar ,&nbsp;Morten Kjos ,&nbsp;Uwe Völker ,&nbsp;Birgitte H. Kallipolitis ,&nbsp;Dorte Frees","doi":"10.1016/j.tcsw.2025.100144","DOIUrl":"10.1016/j.tcsw.2025.100144","url":null,"abstract":"<div><div>A defining feature of bacteria is the peptidoglycan cell wall which provides structural integrity and prevents osmotic lysis. While peptidoglycan hydrolases are required for daughter cell separation, dysregulated cell wall degradation may result in cell lysis. The mechanisms allowing bacteria to control these deadly enzymes in response to environmental changes remain incompletely understood. Here, we find that in <em>Staphylococcus aureus</em>, temperature-dependent regulation of such hydrolases occurs by the coordinated action of a CHAP domain-specific regulatory RNA and the ClpXP protease. Using a proteomics approach, we identify a hitherto uncharacterized <u>C</u>lp<u>X</u>P <u>c</u>ontrolled <u>a</u>utolysin, CxcA, with a catalytic CHAP domain and show that it contributes to separation of daughter cells. CxcA is positively controlled by a non-coding RNA, named Rbc1 (for RNA <u>b</u>inding to CHAP domain) transcribed from the antisense strand of <em>cxcA</em>. Notably, Rbc1 is capable of base pairing with RNAs encoding the CHAP domains of numerous cell wall hydrolases and we show that Rbc1 works <em>in trans</em> to upregulate the cell division hydrolase Sle1. Specifically, Rbc1 functions as a thermosensor allowing for upregulation of CxcA and Sle1 at low temperature where daughter cell separation is impeded. Interestingly, the Rbc1-mediated up-regulation of CxcA and Sle1 does not involve mRNA stabilization or increased translation; instead, Rbc1 depletion increases ClpXP-mediated degradation. In conclusion, we identify a novel cell division hydrolase that is highly conserved in Staphylococci and show that it is co-regulated with enzymes containing the catalytic CHAP domain via transcriptional regulation, an RNA-RNA temperature sensory mechanism and the ClpXP protease.</div></div>","PeriodicalId":36539,"journal":{"name":"Cell Surface","volume":"13 ","pages":"Article 100144"},"PeriodicalIF":0.0,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144115377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Virtual screening of a random tripeptide library for easily prepared inhibitors of insect chitinolytic enzymes","authors":"Zihan Pang ,&nbsp;Yi Ding ,&nbsp;Huijie Xie ,&nbsp;Xi Jiang ,&nbsp;Tian Liu","doi":"10.1016/j.tcsw.2025.100143","DOIUrl":"10.1016/j.tcsw.2025.100143","url":null,"abstract":"<div><div>Insect molting requires chitinolytic enzymes to hydrolyze the chitin in the old cuticle, making chitinolytic enzyme inhibitors potential insecticides. Naturally occurring peptide chitinase inhibitors, such as argadin and argifin, possess complex non-natural structures, making large-scale production and application difficult. Given that chitinolytic enzymes recognize a core trisaccharide unit, this study integrates both in silico and in vitro approaches to explore the feasibility of using tripeptides as insect chitinolytic enzyme inhibitors. Virtual screening of 8000 random tripeptides identified 202 candidate peptides, which were found to be more hydrophobic and enriched in aromatic amino acids, complementing the properties of the chitinase substrate-binding pocket residues. Four selected peptides were synthesized and their inhibitory activities against chitinolytic enzymes from <em>Ostrinia furnacalis</em> were quantitatively assessed, with QWW exhibiting an IC₅₀ value of 0.2 mM against <em>Of</em>Chi-h. Molecular dynamics simulations indicated that strong hydrogen bonds and π-π interactions were key factors in the high activity of QWW. This study not only expands the chemical space for agricultural chemicals targeting chitinase but also establishes an extendable, peptide-based inhibitor discovery process, which may apply to drug development for other targets.</div></div>","PeriodicalId":36539,"journal":{"name":"Cell Surface","volume":"13 ","pages":"Article 100143"},"PeriodicalIF":0.0,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144067958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Arabinogalactan proteins answer a great puzzle","authors":"Derek T.A. Lamport","doi":"10.1016/j.tcsw.2025.100142","DOIUrl":"10.1016/j.tcsw.2025.100142","url":null,"abstract":"","PeriodicalId":36539,"journal":{"name":"Cell Surface","volume":"13 ","pages":"Article 100142"},"PeriodicalIF":0.0,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143887017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comprehensive phenotypic analysis of multiple gene deletions of α-glucan synthase and Crh-transglycosylase gene families in Aspergillus niger highlighting the versatility of the fungal cell wall","authors":"Katharina J. Ost ,&nbsp;Mark Arentshorst ,&nbsp;Bruno M. Moerschbacher ,&nbsp;Mareike E. Dirks-Hofmeister ,&nbsp;Arthur F.J. Ram","doi":"10.1016/j.tcsw.2025.100141","DOIUrl":"10.1016/j.tcsw.2025.100141","url":null,"abstract":"<div><div>Multiple paralogs are found in the fungal genomes for several genes that encode proteins involved in cell wall biosynthesis. The genome of <em>A. niger</em> contains five genes encoding putative α-1,3-glucan synthases (AgsA-E) and seven genes encoding putative glucan-chitin crosslinking enzymes (CrhA-G). Here, we systematically studied the effects of the deletion of single (<em>agsA</em> or <em>agsE</em>), double (<em>agsA</em> and <em>agsE)</em>, or all five <em>ags</em> genes (<em>agsA-E</em>) present in <em>A. niger</em>. Morphological and biochemical analysis of <em>ags</em> mutants emphasizes the important role of <em>agsE</em> in cell wall integrity, while deletion of other <em>ags</em> genes had minimal impact. Loss of <em>agsE</em> compromised cell wall integrity and altered pellet morphology in liquid cultures.</div><div>Previous studies have indicated that deletion of all <em>crh</em> genes in <em>A. niger</em> did not result in cell wall integrity-related phenotypes. To determine whether the <em>ags</em> and <em>crh</em> gene families have redundant functions, both gene families were deleted using iterative CRISPR/Cas9 mediated genome editing. The 12-fold deletion mutant was viable and did not exhibit growth defects under non-stressing growth conditions. A synergistic effect on cell wall integrity was observed in this 12-fold deletion mutant, particularly when exposed to cell wall-perturbing compounds. The cell wall composition, extractability of glucans by alkali, and scanning electron microscopy analysis showed no differences between the parental strain and mutants lacking <em>ags</em> genes, <em>crh</em> genes, or both. These observations underscore the ability of fungal cells to adapt and secure cell wall integrity, even when two entire cell wall protein-encoding gene families are missing.</div></div>","PeriodicalId":36539,"journal":{"name":"Cell Surface","volume":"13 ","pages":"Article 100141"},"PeriodicalIF":0.0,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143301060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sporothrix brasiliensis Gp70 is a cell wall protein required for adhesion, proper interaction with innate immune cells, and virulence","authors":"Leonardo Padró-Villegas ,&nbsp;Manuela Gómez-Gaviria ,&nbsp;Iván Martínez-Duncker ,&nbsp;Luz A. López-Ramírez ,&nbsp;José A. Martínez-Álvarez ,&nbsp;Gustavo A. Niño-Vega ,&nbsp;Héctor M. Mora-Montes","doi":"10.1016/j.tcsw.2024.100139","DOIUrl":"10.1016/j.tcsw.2024.100139","url":null,"abstract":"<div><div><em>Sporothrix brasiliensis</em> is one of the leading etiological agents of sporotrichosis, a cutaneous and subcutaneous mycosis worldwide distributed. This organism has been recently associated with epidemic outbreaks in Brazil. Despite the medical relevance of this species, little is known about its virulence factors, and most of the information on this subject is extrapolated from <em>Sporothrix schenckii</em>. Here, we generated <em>S. brasiliensis</em> mutants, where <em>GP70</em> was silenced. In <em>S. schenckii</em>, this gene encodes a glycoprotein with adhesive properties required for virulence. The <em>S. brasiliensis GP70</em> silencing led to an abnormal cellular phenotype, with smaller, round yeast-like cells that aggregate. Cell aggregation was disrupted with glucanase, suggesting this phenotype is linked to changes in the cell wall. The cell wall characterization confirmed changes in the structural polysaccharide β-1,3-glucan, which increased in quantity and exposure at the cell surface. This was accompanied by a reduction in protein content and <em>N</em>-linked glycans. Mutant strains with high <em>GP70</em>-silencing levels showed minimal levels of 3-carboxy-cis,cis-muconate cyclase activity, this glycoprotein's predicted enzyme function, and decreased ability to bind laminin and fibronectin. These phenotypical changes coincided with abnormal interaction with human peripheral blood mononuclear cells, where production of IL-1β, IL-17, and IL-22 was reduced and the strong dependence on cytokine stimulation <em>via</em> mannose receptor was lost. Phagocytosis by monocyte-derived macrophages was increased and virulence attenuated in a <em>Galleria mellonella</em> larvae. In conclusion, Gp70 is an abundant cell wall glycoprotein in <em>S. brasiliensis</em> that contributes to virulence and proper interaction with innate immnune cells.</div></div>","PeriodicalId":36539,"journal":{"name":"Cell Surface","volume":"13 ","pages":"Article 100139"},"PeriodicalIF":0.0,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11763198/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143048180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of the Neurospora crassa GH72 family of Laminarin/Lichenin transferases and their roles in cell wall biogenesis","authors":"Apurva Chatrath,&nbsp;Pavan Patel,&nbsp;Protyusha Dey,&nbsp;Stephen J. Free","doi":"10.1016/j.tcsw.2024.100140","DOIUrl":"10.1016/j.tcsw.2024.100140","url":null,"abstract":"<div><div>In <em>Neurospora crassa</em> vegetative hyphae, chitin, β-1,3-glucan (laminarin), and a mixed β-1,3−/β-1,4-glucan (lichenin) are the major cell wall polysaccharides. GH72 enzymes have been shown to function as β-1,3-glucanases and glucanosyltransferases and can function in crosslinking β-1,3-glucans together. To characterize the enzymatic activities of the <em>N. crassa</em> enzymes, we expressed GEL-1 with a HIS6 tag in <em>N. crassa.</em> A chimeric maltose binding protein:GEL-2 was produced in <em>E. coli</em>. Purified GEL-1 and GEL-2 were used to characterize their enzymatic activities. We employed thin-layer chromatography (TLC) and polyacrylamide carbohydrate gel electrophoresis (PACE) assays to visualize GEL-1 and GEL-2 hydrolase and transferase activities on lichenin and laminarin substrates. We determined that GEL-1 functions as a laminarinase (β-1,3-glucanase) and as a laminarin transferase. We found that GEL-2 can function as a laminarinase and as a licheninase (β-1,3−/β-1,4-mixed-glucanase) and can crosslink β-1,3-glucans together. We demonstrated that GEL-2 can form enzyme:lichenin intermediates, providing evidence that GEL-2 functions as a lichenin transferase as well as a β-1,3-glucan transferase and crosslinks both types of polysaccharides into the <em>N. crassa</em> cell wall.</div></div>","PeriodicalId":36539,"journal":{"name":"Cell Surface","volume":"13 ","pages":"Article 100140"},"PeriodicalIF":0.0,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11758075/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143047334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Endocytic tethers modulate unconventional GAPDH secretion","authors":"Michael J. Cohen ,&nbsp;Brianne Philippe ,&nbsp;Peter N. Lipke","doi":"10.1016/j.tcsw.2024.100138","DOIUrl":"10.1016/j.tcsw.2024.100138","url":null,"abstract":"<div><div>Yeast cell walls contain both classically-secreted and unconventionally-secreted proteins. The latter class lacks the signal sequence for translocation into the ER, therefore these proteins are transported to the wall by uncharacterized mechanisms. One such protein is the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) which is abundant in the cytosol, but also found in the yeast cell wall where it is enzymatically active. We screened diploid <em>Saccharomyces cerevisiae</em> homozygous gene deletions for changes in cell wall GAPDH activity. Deletions targeting endocytic tethers in the endolysosomal system had the largest effects on GAPDH secretion, including <em>vps21, bro1, vps41, and pep12</em>. The predominant GAPDH isoform Tdh3 was partially localized to endolysosomal compartments, including multivesicular bodies, which are common entry points to unconventional protein secretion pathways. Yeast lacking the endosomal Rab5-GTPase Vps21 had defects in GAPDH secretion as well as delayed entry into to the endolysosomal compartments. Therefore, we conclude that entry into the endolysosomal compartment facilitates non-conventional secretion of GAPDH.</div></div>","PeriodicalId":36539,"journal":{"name":"Cell Surface","volume":"13 ","pages":"Article 100138"},"PeriodicalIF":0.0,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11742311/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143013387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mucilicious methods: Navigating the tools developed to Arabidopsis Seed Coat Mucilage analysis","authors":"Susana Saez-Aguayo ,&nbsp;Dayan Sanhueza ,&nbsp;Vicente Jara ,&nbsp;Benjamin Galleguillos ,&nbsp;Alfonso Gonzalo de la Rubia ,&nbsp;Asier Largo-Gosens ,&nbsp;Adrian Moreno","doi":"10.1016/j.tcsw.2024.100134","DOIUrl":"10.1016/j.tcsw.2024.100134","url":null,"abstract":"<div><div>During the last decades, Arabidopsis seed mucilage has been extensively studied to gain insight into the metabolism of pectin, hemicellulose and cellulose. This review aims to provide a comprehensive examination of the techniques used to understand the composition and structure of <em>Arabidopsis</em> mucilage. Moreover, we present novel findings from mucilage analysis, including the separation of pectic domains within the mucilage, offering a fresh perspective on utilizing traditional techniques to analyze mucilage mutant lines.</div></div>","PeriodicalId":36539,"journal":{"name":"Cell Surface","volume":"13 ","pages":"Article 100134"},"PeriodicalIF":0.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11696855/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142932907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Staphylococcus aureus: Current perspectives on molecular pathogenesis and virulence","authors":"Abayeneh Girma","doi":"10.1016/j.tcsw.2024.100137","DOIUrl":"10.1016/j.tcsw.2024.100137","url":null,"abstract":"<div><div><em>Staphylococcus aureus</em> has evolved a sophisticated regulatory system to control its virulence. One of the main roles of this interconnected network is to sense and respond to diverse environmental signals by altering the synthesis of virulence components required for survival in the host, including cell surface adhesins, extracellular enzymes and toxins. The accessory gene regulator (agr), a quorum sensing system that detects the local concentration of a cyclic peptide signaling molecule, is one of the well-studied of these <em>S</em>. <em>aureus</em> regulatory mechanisms. By using this system, S. aureus is able to sense its own population density and translate this information into a specific pattern of gene expression. In addition to Agr, this pathogen senses specific stimuli through various two-component systems and synchronizes responses with alternative sigma factors and cytoplasmic regulators of the SarA protein family. These different regulatory mechanisms combine host and environmental information into a network that guarantees the best possible response of pathogens to changing circumstances. In this article, an overview of the most significant and thoroughly studied regulatory systems of <em>S</em>. <em>aureus</em> is provided, along with a summary of their roles in host interactions.</div></div>","PeriodicalId":36539,"journal":{"name":"Cell Surface","volume":"13 ","pages":"Article 100137"},"PeriodicalIF":0.0,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11699754/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142932905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatiotemporal regulation of alginate sub-structures at multiple scales revealed by monoclonal antibodies","authors":"Catherine T. Jones ,&nbsp;Cassie Bakshani ,&nbsp;Ieva Lelenaite ,&nbsp;Jozef Mravec ,&nbsp;Stjepan Krešimir Kračun ,&nbsp;Jeff Pearson ,&nbsp;Mathew D. Wilcox ,&nbsp;Kevin Hardouin ,&nbsp;Sonia Kridi ,&nbsp;Cécile Hervé ,&nbsp;William G.T. Willats","doi":"10.1016/j.tcsw.2024.100136","DOIUrl":"10.1016/j.tcsw.2024.100136","url":null,"abstract":"<div><div>Alginates are abundant linear polysaccharides produced by brown algae and some bacteria. They have multiple biological roles and important medical and commercial uses. Alginates are comprised of D-mannuronic acid (M) and L-guluronic acid (G) and the ratios and distribution patterns of M and G profoundly impact their physiological and rheological properties. The structure/function relationships of alginates have been extensively studied in vitro but our understanding of the in vivo spatiotemporal regulation of alginate fine structures and their biological implications is limited. Monoclonal antibodies (mAbs) are powerful tools for localising and quantifying glycan structures and several alginate-directed mAbs have been developed. We used a library of well-defined alginates, with M and G block ratios determined by NMR, to refine our understanding of the binding properties of alginate-directed mAbs. Using these probes, we obtained new insight into how structural features of alginates are regulated at different scales, from cellular to seasonal.</div></div>","PeriodicalId":36539,"journal":{"name":"Cell Surface","volume":"13 ","pages":"Article 100136"},"PeriodicalIF":0.0,"publicationDate":"2024-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11755070/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143030014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}