Molecular Microbiology最新文献

{"title":"Protein STM3547 From Salmonella typhimurium Is a Phosphofructose Kinase B-Type Enzyme With Ribose Kinase Activity.","authors":"Regan D McCormick, Aatif A Jabbar, Jorge C Escalante-Semerena","doi":"10.1111/mmi.70084","DOIUrl":"10.1111/mmi.70084","url":null,"abstract":"<p><p>The first step in the metabolic utilization of ribose is the phosphorylation of its 5' hydroxyl group. The enteropathogenic bacterium Salmonella enterica subsp. enterica sv. Typhimurium str. LT2 (hereafter S. Typhimurium) has two known enzymes that can phosphorylate D-ribose, namely ribose kinase (RbsK) and deoxyribose kinase (DeoK). Here, we report in vivo and in vitro evidence to support the conclusion that the previously uncharacterized STM3547 protein of this bacterium has ribose kinase activity, and we propose naming it RikA (Ribokinase A). Our bioinformatics analyses show end-to-end sequence identity/similarity among RikA, RbsK, and DeoK, and site-directed mutagenesis of RikA showed that, like in RbsK and DeoK, an aspartate residue (position 343 in RikA) is critical for enzymatic activity. We found that RikA has K_m values comparable to those of RbsK and DeoK for both ribose and ATP, and that all three proteins display cooperative binding of ATP induced by ribose. Together, these data suggest that the ribose-induced conformational changes observed in E. coli RbsK also occur in all three ribose kinases of S. typhimurium. Notably, while RikA has robust ribose kinase activity, it can only poorly phosphorylate 2-deoxy-D-ribose, D-xylose, and D-xylulose, and it cannot phosphorylate L-arabinose. Collectively, our data support the conclusion that the RikA protein is a member of the phosphofructose kinase B-type (PfkB) family of sugar kinases.</p>","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":" ","pages":"129-144"},"PeriodicalIF":3.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13432705/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148175844","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":"Nitric Oxide Tunes Secreted Metabolite Bioactivity.","authors":"Zachery R Lonergan, Sarah L Weisflog, Matthew Scurria, Jinyang Li, Korbinian Thalhammer, Osvaldo Gutierrez, Stuart J Conway, Dianne K Newman","doi":"10.1111/mmi.70083","DOIUrl":"10.1111/mmi.70083","url":null,"abstract":"<p><p>The radical nitric oxide (·NO) is short-lived but has imprinted itself on many aspects of physiology and disease. ·NO's rapid production and consumption, coupled with its intrinsic reactivity, drive its biological importance; thus, defining mechanisms and targets of ·NO reactivity is necessary to assess its fate and impact. Cellular small molecules are a major class of ·NO-reactive targets, possessing a variety of molecular functionalities that can react with ·NO. Yet the capacity for secreted small molecules to react with ·NO, as well as the biological consequences of such reactivity, have received little attention. Here, we explore the reactivity of ·NO with phenazine metabolites, microbially-derived secreted small molecules that possess antibiotic properties and can modulate their microenvironment. Using Pseudomonas aeruginosa as a model phenazine producer, we find that ·NO reacts with specific phenazines to yield stable, chemically distinct products. These chemical transformations significantly attenuate phenazine antibiotic properties, including against the phenazine nonproducer Staphylococcus aureus, a competitor with P. aeruginosa for niches in the context of infection. By contrast, P. aeruginosa experiences rapid loss in viability when phenazines and ·NO react. This toxicity occurs even in the presence of S. aureus, which displays resistance to nitrosylated phenazines, implicating a specific toxicity dependent on the formation of the phenazine-NO adduct. These findings highlight the capacity of ·NO to transform metabolite activity and suggest that ·NO can tune microbial interactions in complex environments by a mechanism of action hitherto unappreciated.</p>","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":" ","pages":"145-160"},"PeriodicalIF":3.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13251328/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148205483","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 Master Regulator Spo0A Integrates DNA Sequence and Shape to Regulate the Sporulation Kinase Gene kinA in Bacillus subtilis","authors":"Syeda Hira Zahid, Brenda Zarazúa‐Osorio, Renee Escobedo, Saeed Ullah, Supurna K. Kahavidanalage Dona, Masaya Fujita","doi":"10.1111/mmi.70100","DOIUrl":"https://doi.org/10.1111/mmi.70100","url":null,"abstract":"Sporulation in starved <jats:styled-content style=\"fixed-case\"> <jats:italic>Bacillus subtilis</jats:italic> </jats:styled-content> depends on precise control of <jats:italic>kinA</jats:italic> , which encodes the major phosphorelay kinase that generates the threshold level of phosphorylated Spo0A (Spo0A~P) required for entry into sporulation. Here, we define the regulatory logic that shapes <jats:italic>kinA</jats:italic> expression and uncover structural features that influence Spo0A~P recruitment. First, we show that the <jats:italic>kinA</jats:italic> promoter integrates positive and negative Spo0A~P inputs through a composite three‐site 0A‐box architecture. Distinct affinities and cooperative interactions among the three sites generate a controlled output in which activating and repressive inputs are balanced during starvation, maintaining basal‐to‐moderate <jats:italic>kinA</jats:italic> transcription. Second, we identify intrinsic DNA bending as a sequence‐independent mechanism that enhances Spo0A~P engagement, promoting low‐specificity interactions that may contribute to transcriptional regulation and more broadly chromosome organization. Finally, we show that both the <jats:italic>kinA</jats:italic> promoter and KinA protein domains diverge between pathogenic and nonpathogenic <jats:italic>Bacillus</jats:italic> species, reflecting niche‐specific evolutionary pressures on sporulation initiation. Together, these findings support an integrated model in which promoter architecture and DNA shape collectively tune Spo0A~P dependent regulation of <jats:italic>kinA</jats:italic> .","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"43 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148596328","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":"Detection of Ring Structure and Its Flexibility in Periplasmic Region of FliL , Bacterial Flagellar Stator‐Associate Protein, in Marine Vibrio","authors":"Tatsuro Nishikino, Norihiro Takekawa, Raymond Burton‐Smith, Yuki Tajimi, Kazuyoshi Murata, Takayuki Uchihashi, Seiji Kojima, Katsumi Imada, Michio Homma","doi":"10.1111/mmi.70101","DOIUrl":"https://doi.org/10.1111/mmi.70101","url":null,"abstract":"FliL is a conserved single‐transmembrane protein implicated in stator function and load adaptation of bacterial flagellar motors. We analyzed the oligomeric organization and structural plasticity of the periplasmic domain of polar‐flagellum FliL from <jats:styled-content style=\"fixed-case\"> <jats:italic>Vibrio alginolyticus</jats:italic> </jats:styled-content> ( <jats:sup>pof</jats:sup> FliL <jats:sub>C</jats:sub> ) and compared it with detergent‐solubilized full‐length <jats:sup>pof</jats:sup> FliL. Recombinant proteins were purified by affinity and size‐exclusion chromatography (SEC). SEC profiles indicated condition‐dependent assemblies; <jats:sup>pof</jats:sup> FliL <jats:sub>C</jats:sub> eluted broadly at ~100 kDa and partially shifted to ~45 kDa on re‐chromatography, whereas full‐length <jats:sup>pof</jats:sup> FliL eluted as large, heterogeneous assemblies (~180 kDa). Negative‐stain electron microscopy (EM) revealed abundant ~10‐nm rings for <jats:sup>pof</jats:sup> FliL <jats:sub>C</jats:sub> but heterogeneous particles for full‐length protein. Cryo‐EM single‐particle analysis of the <jats:sup>pof</jats:sup> FliL <jats:sub>C</jats:sub> yielded high‐quality two‐dimensional top/bottom‐view class averages that show ring particles with clear subunit repeats; class averages correspond to apparent 10‐, 11‐ and 12‐fold stoichiometries, but severe preferred orientation and sample heterogeneity prevented reliable three‐dimensional reconstruction. High‐speed AFM imaged ~15 nm rings and captured transient subunit rearrangements and opening/closing events; representative AFM frames can be interpreted as 10‐subunit‐like, yet AFM contrast and tip convolution limited unambiguous subunit counting across the population. These complementary data indicate that the <jats:sup>pof</jats:sup> FliL <jats:sub>C</jats:sub> SPFH‐like periplasmic domain forms flexible, dynamic ring oligomers whose stoichiometry and conformation are modulated by membrane association and experimental conditions. We propose that such plasticity enables FliL to act as an adaptable scaffold for stator engagement and mechanosensitive remodeling of the motor.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"16 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148589053","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":"A Spontaneous Mutation in tfo X Impairs Bioluminescence in Photobacterium kishitanii ANT ‐2200","authors":"Capucine Le Cam Ligier, Gwenola Simon, Charlotte Berthelier, Corinne Valette, Elisa Lefeuvre, Marc Garel, Laurie Casalot","doi":"10.1111/mmi.70104","DOIUrl":"https://doi.org/10.1111/mmi.70104","url":null,"abstract":"Bioluminescence in luminous Vibrionaceae is often regulated by quorum sensing, yet several <jats:italic>Photobacterium</jats:italic> strains emit light independently of cell density, suggesting alternative regulatory inputs. Here, we characterized DimLum, a spontaneous, stable low‐luminescence mutant of <jats:styled-content style=\"fixed-case\"> <jats:italic>Photobacterium kishitanii</jats:italic> </jats:styled-content> ANT‐2200. RNA‐seq showed a pronounced downregulation of the <jats:italic>lux–rib</jats:italic> operon, while whole‐genome sequencing identified a 20‐nucleotide deletion in <jats:italic>tfo</jats:italic> X predicted to truncate the C‐terminal region of TfoX. Complementation with the wild‐type <jats:italic>tfo</jats:italic> X gene restored <jats:italic>lux–rib</jats:italic> expression and bioluminescence, linking this mutation to the DimLum phenotype. The mutant also displayed a limited transcriptional response, including upregulation of a small set of genes such as a Cro/C1‐type regulator. Together, these results identify TfoX as an important component of the regulatory network supporting bioluminescence in <jats:styled-content style=\"fixed-case\"> <jats:italic>P. kishitanii</jats:italic> </jats:styled-content> .","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"14 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148589054","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":"AP2XI ‐3 is Critical for the Cell Cycle of Toxoplasma to Progress Through the G1 Phase","authors":"Fuqiang Fan, Xiaoyan Yin, Anqi Liu, Lilan Xue, Jinling Chen, Yangfan Xu, Bang Shen","doi":"10.1111/mmi.70099","DOIUrl":"https://doi.org/10.1111/mmi.70099","url":null,"abstract":"Toxoplasmosis caused by the Apicomplexan parasite <jats:italic>Toxoplasma gondii</jats:italic> is a significant health threat to immunocompromised individuals and newborns. This parasite has a complex life cycle that is well controlled to achieve optimal transmission and pathogenesis. Acute phase of the disease is caused by rapid proliferation of tachyzoites, which has a highly coordinated and tightly regulated cell cycle to allow parasite propagation. Tachyzoite cell cycle has five partially overlapping phases (G1, S, G2, M and C) with distinct gene expression patterns and cellular activities, yet the underlying regulatory mechanisms are not well understood. In this study, we show that the AP2 family transcription factor AP2XI‐3 has important roles in regulating the cell cycle to progress through the G1 phase. Depletion of AP2XI‐3 resulted in cell cycle retention at G1, leading to growth inhibition of tachyzoites. RNA‐Seq and CUT&amp;Tag analyses revealed that AP2XI‐3 regulates the transcription of genes involved in nucleic acid metabolism, RNA biogenesis and processing, which are consistent with the cellular activities of G1 phase in preparing biomass for cell cycle progression. Moreover, AP2XI‐3 binds to the conserved DNA motif, TRP‐2, a sequence widely distributed in the promoters of genes that exhibit peak expression during the G1 phase. Together, these findings underscore the essential role of AP2XI‐3 in the tight regulation of the G1 phase, highlighting its potential as a therapeutic target for drug development.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"44 8 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148589055","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":"A Novel Plasmodium berghei Protein, LSMP, Regulates Malaria Liver Stage Maturation.","authors":"Rohini Nandi,Akancha Mishra,Shabeer Ali,Satish Mishra","doi":"10.1111/mmi.70097","DOIUrl":"https://doi.org/10.1111/mmi.70097","url":null,"abstract":"Malaria parasites undergo extensive replication in hepatocytes before initiating the pathogenic blood stage of infection. Although this clinically silent phase is essential for parasite expansion, the molecular mechanisms regulating late liver stage maturation remain incompletely understood. Here, we characterize a previously unannotated protein (PBANKA_0620800), which we designate liver stage maturation protein (LSMP). LSMP was expressed during schizont, sporozoite, and liver stages and localized predominantly to the parasite cytosol. Using reverse genetic approaches, we generated LSMP KO parasites and examined their development across the parasite life cycle. Loss of LSMP did not affect asexual blood-stage replication or mosquito-stage development, including ookinete formation, oocyst development, and sporozoite formation. LSMP KO sporozoites invaded hepatocytes normally but exhibited pronounced defects during late liver stage development, including reduced nuclear replication, impaired merozoite formation, and delayed rupture of the parasitophorous vacuole membrane. Together, our findings demonstrate that LSMP is important for malaria liver stage maturation.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"22 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148522074","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":"Divergent Autophagy Pathways in Plasmodium : Mechanisms, Functions, and Therapeutic Potential","authors":"Suryansh Rajput, Pragya Mehra, Rohini Nandi, Raksha Devi, Eisha Pandey, Aastha Varshney, Satish Mishra","doi":"10.1111/mmi.70096","DOIUrl":"https://doi.org/10.1111/mmi.70096","url":null,"abstract":"Autophagy is a highly conserved degradative and recycling pathway essential for maintaining cellular homeostasis. Although its molecular machinery is well characterized in yeast and mammalian systems, it is less studied in the early‐diverging apicomplexan parasite <jats:italic>Plasmodium</jats:italic> , the causative agent of malaria. <jats:italic>Plasmodium</jats:italic> possesses a reduced yet functional repertoire of autophagy‐related (ATG) proteins, suggesting adaptations of this pathway to parasite‐specific biology. Among these, ATG8, a ubiquitin‐like protein, has emerged as a central marker and key effector of plasmodial autophagy. Its branched localization and association with the relict plastid (apicoplast) membrane indicate roles beyond canonical degradative autophagy, particularly in organelle maintenance and biogenesis. ATG7, an essential E1‐like enzyme, activates ATG8 and facilitates its lipidation, thereby regulating organelle turnover and development. This process is further supported by a conserved conjugation system involving ATG3 (E2‐like enzyme) and the ATG12, ATG5, ATG16 complex, functioning as a ligase to enable ATG8 membrane association. ATG4, a cysteine protease, is critical for recycling lipidated ATG8 and maintaining its cytosolic pool, while the homolog Otu can partially compensate for its function. ATG18 also plays an important role in apicoplast biogenesis and maintenance. Collectively, these findings highlight both canonical and non‐canonical roles of autophagy proteins in <jats:italic>Plasmodium</jats:italic> , driving metabolic reprogramming, intracellular remodeling, and stage‐specific differentiation, and support their potential as targets for new antimalarial therapies.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"33 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148498911","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":"A Nutrient‐Responsive LuxR Regulator Orchestrates Effector Gene Expression Across the Legionella Genus","authors":"Chen Adler, Gil Segal","doi":"10.1111/mmi.70095","DOIUrl":"https://doi.org/10.1111/mmi.70095","url":null,"abstract":"<jats:styled-content style=\"fixed-case\"> <jats:italic>Legionella pneumophila</jats:italic> </jats:styled-content> utilizes the Icm/Dot secretion system to translocate &gt; 330 effectors into host cells, yet the regulatory mechanisms controlling the expression of many effector‐encoding genes (EEGs) remain unknown. Here, we identify and characterize LexR1 (lpg2524), a LuxR‐type transcriptional regulator that controls EEG expression in <jats:styled-content style=\"fixed-case\"> <jats:italic>L. pneumophila</jats:italic> </jats:styled-content> and other <jats:italic>Legionella</jats:italic> species. In <jats:styled-content style=\"fixed-case\"> <jats:italic>L. pneumophila</jats:italic> </jats:styled-content> , LexR1 directly activates the expression of four EEGs ( <jats:italic>lem26, lem16, ravW,</jats:italic> and <jats:italic>legC1)</jats:italic> by binding a conserved inverted repeat located upstream of these genes. We demonstrate that LexR1 activity is stimulated by a nutrient‐derived ligand present in casamino acids, and orthologs from other <jats:italic>Legionella</jats:italic> species exhibit similar casamino acid dependent activation of their target genes. Genomic analyses identified 29 genes containing the LexR1 regulatory element in the seven <jats:italic>Legionella</jats:italic> species containing LexR1, most of which encode validated effectors or proteins harboring common effector domains. Many of these genes are shared among the species and appear to have co‐transferred with their regulatory regions via horizontal gene transfer. LexR1 expression is positively regulated by RpoS and repressed by Fis, linking it to the broader effector regulatory network. Together, these findings identify LexR1 as a regulator of EEGs that coordinates nutrient sensing with effector gene expression across the <jats:italic>Legionella</jats:italic> genus.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"31 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148428788","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":"The Synergy Between a Silver‐Ruthenium Antimicrobial and Aminoglycosides Is Based on Severe Macromolecular Damage","authors":"Emmanuel P. Oladokun, Gracious Y. Donkor, Julius K. Narh, Grady D. Jacobson, Cade Ward, Patrick O. Tawiah, Lisa K. Polzer, Kevin A. Edwards, Kyle A. Floyd, Jan‐Ulrik Dahl","doi":"10.1111/mmi.70094","DOIUrl":"https://doi.org/10.1111/mmi.70094","url":null,"abstract":"The rise of multidrug‐resistant (MDR) bacterial pathogens, including uropathogenic <jats:styled-content style=\"fixed-case\"> <jats:italic>Escherichia coli</jats:italic> </jats:styled-content> (UPEC), highlights the urgent need for alternative treatment strategies to restore antibiotic efficacy. The silver‐ruthenium antimicrobial AGXX exerts potent bactericidal effects through the production of reactive oxygen species (ROS); however, its potential synergy with antibiotics has not been thoroughly investigated. Here, we show that sublethal concentrations of AGXX strongly enhance aminoglycoside‐mediated killing across a diverse panel of Gram‐negative and Gram‐positive MDR clinical isolates, including highly aminoglycoside‐resistant strains. Combinational treatments significantly reduced the effective concentrations of gentamicin, tobramycin, kanamycin, and amikacin required to kill bacteria. Mechanistic analyses revealed that AGXX/aminoglycoside co‐treatments induce pronounced intracellular ROS accumulation, resulting in an imbalanced proteostasis due to extensive protein aggregation and DNA damage. Scavenging ROS abolished synergistic killing, establishing oxidative imbalance as the primary driver of the synergy between both antimicrobials. We further identified polyphosphate as a key bacterial defense mechanism that mitigates ROS accumulation, proteotoxicity, and genotoxic stress during combinational treatment. Moreover, AGXX–aminoglycoside synergy was preserved in an artificial urine medium and across clinical UPEC isolates, underscoring its relevance to urinary tract infections. Together, these findings position AGXX as a potent aminoglycoside adjuvant that restores antibiotic efficacy through ROS‐driven macromolecular damage, supporting its development for combination therapies against MDR bacterial infections.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"29 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2026-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148415395","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}