Microbiological research最新文献

{"title":"Decoding bacterial communication: Intracellular signal transduction, quorum sensing, and cross-kingdom interactions.","authors":"Shuxun Liu, Xujie Feng, Hangjia Zhang, Ping Li, Baoru Yang, Qing Gu","doi":"10.1016/j.micres.2024.127995","DOIUrl":"https://doi.org/10.1016/j.micres.2024.127995","url":null,"abstract":"<p><p>This review provides a comprehensive analysis of the intricate architecture of bacterial sensing systems, with a focus on signal transduction mechanisms and their critical roles in microbial physiology. It highlights quorum sensing (QS), quorum quenching (QQ), and quorum sensing interference (QSI) as fundamental processes driving bacterial communication, influencing gene expression, biofilm formation, and interspecies interactions. The analysis explores the importance of diffusible signal factors (DSFs) and secondary messengers such as cAMP and c-di-GMP in modulating microbial behaviors. Additionally, cross-kingdom signaling, where bacterial signals impact host-pathogen dynamics and ecological balance, is systematically reviewed. This review introduces \"signalomics\", an novel interdisciplinary framework integrating genomics, proteomics, and metabolomics to offer a holistic framework for understanding microbial communication and evolution. These findings hold significant implications for various domains, including food preservation, agriculture, and human health.</p>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"292 ","pages":"127995"},"PeriodicalIF":6.1,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142807159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Candidatus Liberibacter asiaticus exploits cytoskeletal system of psyllid vector for circulative propagative infection.","authors":"Zhiqiang Li, Xiao Yang, Yuxin Guo, Xiaofeng Zhang, You Li, Yen-Wen Kuo, Taiyun Wei, Qian Chen","doi":"10.1016/j.micres.2024.127985","DOIUrl":"https://doi.org/10.1016/j.micres.2024.127985","url":null,"abstract":"<p><p>The citrus disease Huanglongbing (HLB) in Asia and the US is caused by Candidatus Liberibacter asiaticus (CLas), which is primarily transmitted by Diaphorina citri, also known as Asian citrus psyllid in a persistent and propagative manner. However, the exact mechanisms underlying CLas circulation within D. citri remain largely unclear. Here, immunofluorescence microscopy and electron microscopy were utilized to track the sequential infection of CLas in D. citri, from alimentary canal to salivary glands, and ultimately to the plant host. CLas was found to initially infect the epithelium of filter chamber, after which it rapidly spreads to visceral muscles for further infection throughout the alimentary canal. The rapid spread in D. citri adults causes the duration of CLas circulation to be as short as 9 days. The duration of latent period may be explained by the recruitment of cytoskeletal α-actinin by the outer membrane protein (OMP) of CLas. Inhibition of actin filament or knocking down the expression of α-actinin significantly suppresses CLas cytoskeleton-dependent infection in and spread among D. citri organs. Injection of prokaryotically expressed OMP into D. citri also recruits α-actinin, resembling the natural infection of CLas. Our studies showed that CLas exploits α-actinin and remolds actin machinery of D. citri for overcoming the midgut release barrier, facilitating its circulation in the vector. By shedding light on these mechanisms, this report reveals more detailed mechanisms in CLas infection in D. citri, and offers a plausible explanation for rapid dissemination of HLB in nature from the perspective of psyllid transmission.</p>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"292 ","pages":"127985"},"PeriodicalIF":6.1,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142823836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanism and nanotechnological-based therapeutics for tolerance and resistance of bacterial biofilms.","authors":"Beiliang Miao, Dianhong Wang, Li Yu, Xiangfei Meng, Shiyi Liu, Mengqi Gao, Jiatong Han, Zeliang Chen, Ping Li, Shiwei Liu","doi":"10.1016/j.micres.2024.127987","DOIUrl":"https://doi.org/10.1016/j.micres.2024.127987","url":null,"abstract":"<p><p>Bacterial biofilms are one of the most relevant drivers of chronic and recurrent infections and a significant healthcare problem. Biofilms were formed by cross-linking of hydrophobic extracellular polymeric substances (EPS), such as proteins, polysaccharides, and eDNA, which were synthesized by bacteria themselves after adhesion and colonization on biological surfaces. They had the characteristics of dense structure and low drug permeability, leading to tolerance and resistance of biofilms to antibiotics and to host responses. Within a biofilm, microbial cells show increased tolerance to both immune system defense mechanisms and antimicrobials than the same cells in the planktonic state. It is one of the key reasons for the failure of traditional clinical drug to treat infectious diseases. Currently, no drugs are available to attack bacterial biofilms in the clinical setting. The development of novel preventive and therapeutic strategies is urgently needed to allow an effective management of biofilm-associated infections. Based on the properties of nanomaterials and biocompatibility, nanotechnology had the advantages of specific targeting, intelligent delivery and low toxicity, which could realize efficient intervention and precise treatment of biofilm-associated infections. In this paper, the mechanisms of bacterial biofilm resistance to antibiotics and host response tolerance were elaborated. Meanwhile, This paper highlighted multiple strategies of biofilms eradication based on nanotechnology. Nanotechnology can interfere with biofilm formation by destroying mature biofilm, modulating biofilm heterogeneity, inhibiting bacterial metabolism, playing antimicrobial properties, activating immunity and enhancing biofilm penetration, which is an important new anti-biofilm preparation. In addition, we presented the key challenges still faced by nanotechnology in combating bacterial biofilm infections. Utilization of nanotechnology safely and effectively should be further strengthened to confirm the safety aspects of their clinical application.</p>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"292 ","pages":"127987"},"PeriodicalIF":6.1,"publicationDate":"2024-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142791799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Arginine kinase McsB and ClpC complex impairs the transition to biofilm formation in Bacillus subtilis.","authors":"Jie Zhang, Panlei Yang, Qingchao Zeng, Yiwei Zhang, Yanan Zhao, Liwei Wang, Yan Li, Zhenshuo Wang, Qi Wang","doi":"10.1016/j.micres.2024.127979","DOIUrl":"https://doi.org/10.1016/j.micres.2024.127979","url":null,"abstract":"<p><p>Robust biofilm formation on host niches facilitates beneficial Bacillus to promote plant growth and inhibit plant pathogens. Arginine kinase McsB is involved in bacterial development and stress reaction by phosphorylating proteins for degradation through a ClpC/ClpP protease. Conversely, cognate arginine phosphatase YwlE counteracts the process. Regulatory pathways of biofilm formation have been studied in Bacillus subtilis, of which Spo0A∼P is a master transcriptional regulator, which is transcriptionally activated by itself in biofilm formation. Previous studies have shown that Spo0A∼P transcript regulation controls biofilm formation, where MecA binds ClpC to inhibit Spo0A∼P-dependent transcription without triggering degradation. It remains unclear whether McsB and ClpC regulate biofilm formation together and share a similar non-proteolytic mechanism like MecA/ClpC complex. In this study, we characterized McsB and ClpC as negative regulators of biofilm formation and matrix gene eps expression. Our genetic and morphological evidence further indicates that McsB and ClpC inhibit eps expression by decreasing the spo0A and sinI expression, leading to the release of SinR, a known repressor of eps transcription. Given that the spo0A and sinI expression is transcriptionally activated by Spo0A∼P in biofilm formation, we next demonstrate that McsB interacts with Spo0A directly by bacterial two-hybrid system and Glutathione transferase pull-down experiments. Additionally, we present that McsB forms a complex with ClpC to dampen biofilm formation in vivo. Finally, we show that YwlE acts as a positive regulator of biofilm formation, counteracting the function of McsB. These findings suggest that McsB, ClpC, and YwlE play vital roles in the transition to biofilm formation in Bacillus subtilis, providing new insights into the regulatory mechanisms underlying biofilm development and sharing a similar non-proteolytic mechanism in biofilm formation as MecA/ClpC complex.</p>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"292 ","pages":"127979"},"PeriodicalIF":6.1,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142823835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Natterin-like and legumain insect gut proteins promote the multiplication of a vector-borne bacterial plant pathogen","authors":"Luciana Galetto ,&nbsp;Giulia Lucetti ,&nbsp;Luca Bucci ,&nbsp;Francesca Canuto ,&nbsp;Marika Rossi ,&nbsp;Simona Abbà ,&nbsp;Marta Vallino ,&nbsp;Cecilia Parise ,&nbsp;Sabrina Palmano ,&nbsp;Marcello Manfredi ,&nbsp;Domenico Bosco ,&nbsp;Cristina Marzachì","doi":"10.1016/j.micres.2024.127984","DOIUrl":"10.1016/j.micres.2024.127984","url":null,"abstract":"<div><div>Phytoplasmas are phloem-limited plant pathogenic bacteria causing diseases in many plant species. They are transmitted by Hemipteran insect species in a persistent-propagative manner. Phytoplasmas are wall-less, and their membrane proteins are involved in pathogen internalization into host cells. We focused on the immunodominant membrane protein (Imp) of Flavescence dorée phytoplasma (FDp), a grapevine quarantine pest and a major threat to European viticulture. <em>Scaphoideus titanus</em> is the main natural vector of FDp to grapevine, whereas <em>Euscelidius variegatus</em> is commonly used as laboratory vector. Previous works indicated that recombinant Imp of two FDp strains (FD-C and FD-D) selectively interact with gut proteins from vector species rather than those from non-vectors. Here, similar patterns of interacting insect gut proteins were obtained from both vector species, following pull-down with His-tagged FDp Imps. After identification of several targets, four <em>S. titanus</em> and five <em>E. variegatus</em> proteins interacting with Imp were further characterized by measuring expression in different insect tissues and in healthy vs. infected insects. Specific RNAi silencing of two of these vector genes, namely natterin and legumain, resulted in a significant reduction of phytoplasma multiplication in insects upon pathogen acquisition, compared to control insects. Natterin displays a DM9 domain and legumain possesses a signature of G protein receptor, supporting their involvement as FDp Imp receptors. Outcomes of this work are discussed with particular attention devoted to the gain of knowledge on host/pathogen interaction as well as to the potential impact on improvement phytoplasma disease management.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"291 ","pages":"Article 127984"},"PeriodicalIF":6.1,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phototactic signaling network in rod-shaped cyanobacteria: A study on Synechococcus elongatus UTEX 3055.","authors":"Shang-Yu Li, Chenliu He, Cesar Augusto Valades-Cruz, Cheng-Cai Zhang, Yiling Yang","doi":"10.1016/j.micres.2024.127967","DOIUrl":"https://doi.org/10.1016/j.micres.2024.127967","url":null,"abstract":"<p><p>Light-controlled motility is advantageous for photosynthetic prokaryotes to better survive in environment with constantly changing light conditions. For cyanobacteria, light is both an energy source for photosynthesis and a stress factor. Consequently, some cyanobacteria evolved the ability to control type-IV pili (T4P)-mediated surface motility using a chemotaxis-like system in response to light signals. Extensive studies on the mechanism of phototaxis has been conducted in the spherical Synechocystis sp. PCC 6803 and the filamentous strain Nostoc punctiforme, while less is explored in rod-shaped cyanobacteria such as Synechococcus species. In this study, we investigated the phototaxis pathway in the unicellular rod-shaped cyanobacterium Synechococcus elongatus UTEX 3055, which exhibits bidirectional phototaxis using a single tax1 operon, in contrast to more complex and multiple gene clusters revealed in Synechocystis sp. PCC 6803. Results obtained by protein-protein interaction assays and protein subcellular localization experiments indicated that proteins encoded by the tax1 operon form large clusters that asymmetrically distributed both between the two poles and within the same pole. In vitro phosphorylation assays and site-directed mutations of conserved phosphorylation sites in PixL_Se, PixG_Se and PixH_Se demonstrate that PixL_Se acts as a histidine kinase, and PixG_Se and PixH_Se as response regulators for signal transduction. We further show that PixG_Se and PixH_Se are recruited to cell poles via interactions with the N-terminal region of PixL_Se. While phosphotransfer reactions in this signaling pathway are critical for phototactic signaling, the two response regulators appear to play different roles in the control of phototaxis. This study provides a framework for further investigation into the complex phototactic signaling network in rod-shaped cyanobacteria with clearly defined cell poles in contrast to round shaped Synechocystis species with virtual cells poles through light-lensing effect.</p>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"292 ","pages":"127967"},"PeriodicalIF":6.1,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142786085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Foisc1 regulates growth, conidiation, sensitivity to salicylic acid, and pathogenicity of Fusarium oxysporum f. sp. cubense tropical race 4","authors":"Lijia Guo ,&nbsp;Jun Wang ,&nbsp;You Zhou ,&nbsp;Changcong Liang ,&nbsp;Lei Liu ,&nbsp;Yang Yang ,&nbsp;Junsheng Huang ,&nbsp;Laying Yang","doi":"10.1016/j.micres.2024.127975","DOIUrl":"10.1016/j.micres.2024.127975","url":null,"abstract":"<div><div>The secreted isochorismatases derived from certain filamentous pathogens play vital roles in the infection of host plants by lowering salicylic acid (SA) levels and suppressing SA-mediated defense pathway. However, it remains unclear whether the fungus <em>Fusarium oxysporum</em> f. sp. <em>cubense</em> tropical race 4 (FocTR4), which causes vascular wilt in bananas, utilizes isochorismatases to modulate SA levels in the host and subvert the banana defense system for successful infection. In the current study, we selected and functionally characterized the <em>foisc1</em> gene, one of 10 putative isochorismatase-encoding genes in FocTR4 that showed significant upregulation during early stages of infection. Deletion of <em>foisc1</em> resulted in enhanced vegetative growth and conidiation, increased sensitivity to SA, reduced colonization within host plants, as well as impaired pathogenicity. Conversely, complementation restored phenotypes similar to those observed in the wild-type strain. Furthermore, deletion of <em>foisc1</em> led to a notable rise in activities of defense-related enzymes such as catalase, peroxidase, and phenylalnine ammonialyase; along with an upregulated expression of several defense-related genes including <em>PR</em> genes and <em>NPR1</em> genes within hosts' tissues. The non-secretory nature of Foisc1 protein was confirmed and its absence did not affect SA levels within host plants. Transcriptome analysis revealed that deletion of <em>foisc1</em> resulted in decreased expression levels for numerous genes associated with pathogenicity including those involved in fusaric acid biosynthesis and effector genes as well as a catechol 1,2-dioxygenase gene essential for SA degradation; while increasing expression levels for numerous genes associated with hyphal growth and conidiation were observed instead. Therefore, our findings suggest that Foisc1 may influence hyphal growth, conidiation, sensitivity to SA, and pathogenicity of FocTR4 through modulation of various genes implicated in these processes. These findings provide valuable insights into the pathogenesis of FocTR4, and create a groundwork for the future development of innovative control strategies targeting vascular wilt disease of banana.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"291 ","pages":"Article 127975"},"PeriodicalIF":6.1,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural insights into the advancements of mobile colistin resistance enzymes","authors":"Qi Zhang","doi":"10.1016/j.micres.2024.127983","DOIUrl":"10.1016/j.micres.2024.127983","url":null,"abstract":"<div><div>The plasmid-encoded mobile colistin resistance enzyme (MCR) is challenging the clinical efficacy of colistin as a last-resort antibiotic against multidrug-resistant bacteria. This transferase catalyzes the addition of positively charged phosphoethanolamine to lipid A, and its catalytic domain in the periplasm has been elucidated. To date, there are many works on the catalytic domain and function of this enzyme class. However, the roles of unreported soluble or inter-membrane domains remain undefined, which might cause an inaccurate or even incorrect understanding of substrate recognition and binding. In this review, MCR-1 is first compared and analyzed from the perspective of the full-length alpha-fold MCR-1. Specifically, some disputed issues, especially in its architecture and catalytic mechanism are discussed independently. Meanwhile, the structure-based insights into MCRs variants, their evolutions, and the balance between colistin-resistance and survival costs, are also critically analyzed. Importantly, by comparing it with the full-length MCR-1, several potential pockets for drug design have been re-identified. Finally, recent advancements in inhibitors targeting MCR-1 are also in-depth summarized. These details offer a new perspective on MCRs and serve as a valuable foundation for drug development.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"291 ","pages":"Article 127983"},"PeriodicalIF":6.1,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transcriptional memory drives accelerated re-activation of several biosynthetic gene clusters in Aspergillus nidulans.","authors":"Franz Zehetbauer ,&nbsp;Harald Berger ,&nbsp;Florian Kastner ,&nbsp;Joseph Strauss","doi":"10.1016/j.micres.2024.127981","DOIUrl":"10.1016/j.micres.2024.127981","url":null,"abstract":"<div><div>Organisms are repeatedly exposed to fluctuating environmental and nutritional conditions. Transcriptional memory has been shown to be a mechanism to cope with these fluctuations because it increases the speed and the magnitude of the cellular response to a certain re-occurring condition and therefore optimizes adaptation and fitness in a given environment. We found that genes coding for sterigmatocystin (ST) production in <em>Aspergillus nidulans</em> are activated stronger when cells are repeatedly exposed to nutrient starvation, compared to cells that experience this condition for the first time. We studied possible underlying mechanisms and found that persistence of the transcription factor AflR, which can undergo activation-inactivation cycles, accounts for a large part of the memory. In addition, a chromatin-based mechanism through histone H3 lysine 4 dimethylation (H3K4me2) and extracellular metabolites produced during the first activation phase contribute to the memory process. Genome-wide transcriptome and chromatin analyses showed that only a few genes within the ST and other starvation-induced biosynthetic gene clusters gain the H3K4me2 mark during the 1st activation, but the majority of those which receive the mark also maintain it during the subsequent repression and re-activation phase. Combined with previous findings on chromatin-level regulation of biosynthetic gene clusters (BGCs) our recent data suggest that the H3K4me2 mark may contribute to the correct 3D organization of BGCs and that this is a prerequisite for activation and transcriptional memory.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"291 ","pages":"Article 127981"},"PeriodicalIF":6.1,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142723049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overall mutational scanning unveils the essential active residues for the mechanistic action of MCR-1","authors":"Qipeng Cheng ,&nbsp;Yanchu Cheung ,&nbsp;Chen Xu ,&nbsp;Edward Wai Chi Chan ,&nbsp;Kin Fai Chan ,&nbsp;Sheng Chen","doi":"10.1016/j.micres.2024.127982","DOIUrl":"10.1016/j.micres.2024.127982","url":null,"abstract":"<div><div>Polymyxins, including colistin and polymyxin B, serve as crucial last-resort antibiotics for managing infections caused by carbapenem-resistant Enterobacterales (CRE). However, the rapid spread of the mobilized colistin resistance gene (<em>mcr</em>-1) challenged the efficacy of treatment by polymyxins. The <em>mcr</em>-1 gene encoded a transmembrane phosphoethanolamine (PEA) transferase enzyme, MCR-1. MCR-1 could catalyze the transfer of PEA moiety of phosphatidylethanolamine (PE) to the 1’ (or 4’)-phosphate group of the lipid A. Despite the determination of several structures of the soluble domain of MCR-1, the structural and biochemical mechanisms of integral MCR-1 remain less understood. In this study, we utilized an alanine scanning mutagenesis approach to systematically investigate the functional attributes of distinct regions within MCR-1. We identified fifteen critical residues that are indispensable for the enzymatic activity of MCR-1 and are pivotal for its ability to confer resistance to colistin. Furthermore, molecular docking of MCR-1 complexed with the phosphoethanolamine (PE) substrate revealed the presence of a channel-shaped cavity, a characteristic feature shared with other phosphoethanolamine transferases. Despite MCR-1 exhibiting a low sequence identity with both MCR homologues and other phosphoethanolamine (PEA) transferases, several conserved sites were identified, including Y⁹⁷, M¹⁰⁵, K³³³, H³⁹⁵, L⁴⁷⁷, and H⁴⁷⁸, suggesting a potentially shared catalytic mechanism among them for modifying LPS-lipid A. Overall, these findings provide a deep understanding of the catalytic mechanism of MCR-1 for colistin resistance. Moreover, these findings provide a robust structural and functional foundation, enabling the rational design of targeted inhibitors and restoring colistin activity against serious infections with carbapenem-resistant Enterobacterales (CRE).</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"291 ","pages":"Article 127982"},"PeriodicalIF":6.1,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}