scholarly journals Evolutionary Adaptation of an AraC-Like Regulatory Protein in Citrobacter rodentium and Escherichia Species

2015 ◽  
Vol 83 (4) ◽  
pp. 1384-1395 ◽  
Author(s):  
Aimee Tan ◽  
Nicola K. Petty ◽  
Dianna Hocking ◽  
Vicki Bennett-Wood ◽  
Matthew Wakefield ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Regulatory Protein ◽  
Gene Repertoire ◽  
Citrobacter Rodentium ◽  
Environmental Strain ◽  
Content Type ◽  
E Coli ◽  
Genes Encoding

The evolution of pathogenic bacteria is a multifaceted and complex process, which is strongly influenced by the horizontal acquisition of genetic elements and their subsequent expression in their new hosts. A well-studied example is the RegA regulon of the enteric pathogenCitrobacter rodentium. The RegA regulatory protein is a member of the AraC/XylS superfamily, which coordinates the expression of a gene repertoire that is necessary for full pathogenicity of this murine pathogen. Upon stimulation by an exogenous, gut-associated signal, namely, bicarbonate ions, RegA activates the expression of a series of genes, including virulence factors, such as autotransporters, fimbriae, a dispersin-like protein, and thegrlRAoperon on the locus of enterocyte effacement pathogenicity island. Interestingly, the genes encoding RegA homologues are distributed across the genusEscherichia, encompassing pathogenic and nonpathogenic subtypes. In this study, we carried out a series of bioinformatic, transcriptional, and functional analyses of the RegA regulons of these bacteria. Our results demonstrated thatregAhas been horizontally transferred toEscherichiaspp. andC. rodentium. Comparative studies of two RegA homologues, namely, those fromC. rodentiumandE. coliSMS-3-5, a multiresistant environmental strain ofE. coli, showed that the two regulators acted similarlyin vitrobut differed in terms of their abilities to activate the virulence ofC. rodentiumin vivo, which evidently was due to their differential activation ofgrlRA. Our data indicate that RegA fromC. rodentiumhas strain-specific adaptations that facilitate infection of its murine host. These findings shed new light on the development of virulence byC. rodentiumand on the evolution of virulence-regulatory genes of bacterial pathogens in general.

scholarly journals The Escherichia coli Protein YfeX Functions as a Porphyrinogen Oxidase, Not a Heme Dechelatase

mBio ◽  
2011 ◽  
Vol 2 (6) ◽  
Author(s):  
Harry A. Dailey ◽  
Alecia N. Septer ◽  
Lauren Daugherty ◽  
Daniel Thames ◽  
Svetlana Gerdes ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pathogenic Bacteria ◽  
Iron Removal ◽  
Anaerobic Growth ◽  
Limiting Factor ◽  
Alizarin Red ◽  
Content Type ◽  
E Coli ◽  
Genes Encoding

ABSTRACT The protein YfeX from Escherichia coli has been proposed to be essential for the process of iron removal from heme by carrying out a dechelation of heme without cleavage of the porphyrin macrocycle. Since this proposed reaction is unique and would represent the first instance of the biological dechelation of heme, we undertook to characterize YfeX. Our data reveal that YfeX effectively decolorizes the dyes alizarin red and Cibacron blue F3GA and has peroxidase activity with pyrogallal but not guiacol. YfeX oxidizes protoporphyrinogen to protoporphyrin in vitro. However, we were unable to detect any dechelation of heme to free porphyrin with purified YfeX or in cellular extracts of E. coli overexpressing YfeX. Additionally, Vibrio fischeri, an organism that can utilize heme as an iron source when grown under iron limitation, is able to grow with heme as the sole source of iron when its YfeX homolog is absent. Plasmid-driven expression of YfeX in V. fischeri grown with heme did not result in accumulation of protoporphyrin. We propose that YfeX is a typical dye-decolorizing peroxidase (or DyP) and not a dechelatase. The protoporphyrin reported to accumulate when YfeX is overexpressed in E. coli likely arises from the intracellular oxidation of endogenously synthesized protoporphyrinogen and not from dechelation of exogenously supplied heme. Bioinformatic analysis of bacterial YfeX homologs does not identify any connection with iron acquisition but does suggest links to anaerobic-growth-related respiratory pathways. Additionally, some genes encoding homologs of YfeX have tight association with genes encoding a bacterial cytoplasmic encapsulating protein. IMPORTANCE Acquisition of iron from the host during infection is a limiting factor for growth and survival of pathogens. Host heme is the major source of iron in infections, and pathogenic bacteria have evolved complex mechanisms to acquire heme and abstract the iron from heme. Recently Létoffé et al. (Proc. Natl. Acad. Sci. U. S. A. 106:11719–11724, 2009) reported that the protein YfeX from E. coli is able to dechelate heme to remove iron and leave an intact tetrapyrrole. This is totally unlike any other described biological system for iron removal from heme and, thus, would represent a dramatically new feature with potentially profound implications for our understanding of bacterial pathogenesis. Given that this reaction has no precedent in biological systems, we characterized YfeX and a related protein. Our data clearly demonstrate that YfeX is not a dechelatase as reported but is a peroxidase that oxidizes endogenous porphyrinogens to porphyrins.

scholarly journals A Rhodobacter sphaeroides Protein Mechanistically Similar to Escherichia coli DksA Regulates Photosynthetic Growth

mBio ◽  
2014 ◽  
Vol 5 (3) ◽  
Author(s):  
Christopher W. Lennon ◽  
Kimberly C. Lemmer ◽  
Jessica L. Irons ◽  
Max I. Sellman ◽  
Timothy J. Donohue ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Structure Function ◽  
Rhodobacter Sphaeroides ◽  
Fatty Acid Content ◽  
Regulatory Protein ◽  
Growth Conditions ◽  
Globular Domain ◽  
Content Type ◽  
E Coli

ABSTRACTDksA is a global regulatory protein that, together with the alarmone ppGpp, is required for the “stringent response” to nutrient starvation in the gammaproteobacteriumEscherichia coliand for more moderate shifts between growth conditions. DksA modulates the expression of hundreds of genes, directly or indirectly. Mutants lacking a DksA homolog exhibit pleiotropic phenotypes in other gammaproteobacteria as well. Here we analyzed the DksA homolog RSP2654 in the more distantly relatedRhodobacter sphaeroides, an alphaproteobacterium. RSP2654 is 42% identical and similar in length toE. coliDksA but lacks the Zn finger motif of theE. coliDksA globular domain. Deletion of the RSP2654 gene results in defects in photosynthetic growth, impaired utilization of amino acids, and an increase in fatty acid content. RSP2654 complements the growth and regulatory defects of anE. colistrain lacking thedksAgene and modulates transcriptionin vitrowithE. coliRNA polymerase (RNAP) similarly toE. coliDksA. RSP2654 reduces RNAP-promoter complex stabilityin vitrowith RNAPs fromE. coliorR. sphaeroides, alone and synergistically with ppGpp, suggesting that even though it has limited sequence identity toE. coliDksA (DksAEc), it functions in a mechanistically similar manner. We therefore designate the RSP2654 protein DksARsp. Our work suggests that DksARsphas distinct and important physiological roles in alphaproteobacteria and will be useful for understanding structure-function relationships in DksA and the mechanism of synergy between DksA and ppGpp.IMPORTANCEThe role of DksA has been analyzed primarily in the gammaproteobacteria, in which it is best understood for its role in control of the synthesis of the translation apparatus and amino acid biosynthesis. Our work suggests that DksA plays distinct and important physiological roles in alphaproteobacteria, including the control of photosynthesis inRhodobacter sphaeroides. The study of DksARsp, should be useful for understanding structure-function relationships in the protein, including those that play a role in the little-understood synergy between DksA and ppGpp.

scholarly journals Competing Substrates for the Bifunctional Diaminopimelic Acid Epimerase/Glutamate Racemase Modulate Peptidoglycan Synthesis in Chlamydia trachomatis

2020 ◽  
Vol 89 (1) ◽  
pp. e00401-20
Author(s):  
Raghuveer Singh ◽  
Jessica A. Slade ◽  
Mary Brockett ◽  
Daniel Mendez ◽  
George W. Liechti ◽  
...  
Keyword(s):  
Chlamydia Trachomatis ◽  
Diaminopimelic Acid ◽  
Competition Strategy ◽  
Content Type ◽  
E Coli ◽  
Glutamate Racemase ◽  
Heterologous System ◽  
Substrate Competition

ABSTRACTThe Chlamydia trachomatis genome encodes multiple bifunctional enzymes, such as DapF, which is capable of both diaminopimelic acid (DAP) epimerase and glutamate racemase activity. Our previous work demonstrated the bifunctional activity of chlamydial DapF in vitro and in a heterologous system (Escherichia coli). In the present study, we employed a substrate competition strategy to demonstrate DapFCt function in vivo in C. trachomatis. We reasoned that, because DapFCt utilizes a shared substrate-binding site for both racemase and epimerase activities, only one activity can occur at a time. Therefore, an excess of one substrate relative to another must determine which activity is favored. We show that the addition of excess l-glutamate or meso-DAP (mDAP) to C. trachomatis resulted in 90% reduction in bacterial titers, compared to untreated controls. Excess l-glutamate reduced in vivo synthesis of mDAP by C. trachomatis to undetectable levels, thus confirming that excess racemase substrate led to inhibition of DapFCt DAP epimerase activity. We previously showed that expression of dapFCt in a murI (racemase) ΔdapF (epimerase) double mutant of E. coli rescues the d-glutamate auxotrophic defect. Addition of excess mDAP inhibited growth of this strain, but overexpression of dapFCt allowed the mutant to overcome growth inhibition. These results confirm that DapFCt is the primary target of these mDAP and l-glutamate treatments. Our findings demonstrate that suppression of either the glutamate racemase or epimerase activity of DapF compromises the growth of C. trachomatis. Thus, a substrate competition strategy can be a useful tool for in vivo validation of an essential bifunctional enzyme.

scholarly journals Identification and Regulation of a Novel Citrobacter rodentium Gut Colonization Fimbria (Gcf)

2015 ◽  
Vol 197 (8) ◽  
pp. 1478-1491 ◽  
Author(s):  
Gustavo G. Caballero-Flores ◽  
Matthew A. Croxen ◽  
Verónica I. Martínez-Santos ◽  
B. Brett Finlay ◽  
José L. Puente
Keyword(s):  
Escherichia Coli ◽  
Intestinal Epithelium ◽  
Pathogenic Bacteria ◽  
Critical Role ◽  
Growth Conditions ◽  
Citrobacter Rodentium ◽  
Content Type ◽  
Gut Colonization ◽  
Successful Infection

ABSTRACTThe Gram-negative enteric bacteriumCitrobacter rodentiumis a natural mouse pathogen that has been extensively used as a surrogate model for studying the human pathogens enteropathogenic and enterohemorrhagicEscherichia coli. All three pathogens produce similar attaching and effacing (A/E) lesions in the intestinal epithelium. During infection, these bacteria employ surface structures called fimbriae to adhere and colonize the host intestinal epithelium. ForC. rodentium, the roles of only a small number of its genome-carried fimbrial operons have been evaluated. Here, we report the identification of a novelC. rodentiumcolonization factor, calledgutcolonizationfimbria (Gcf), which is encoded by a chaperone-usher fimbrial operon. AgcfAmutant shows a severe colonization defect within the first 10 days of infection. Thegcfpromoter is not active inC. rodentiumunder severalin vitrogrowth conditions; however, it is readily expressed in aC. rodentiumΔhns1mutant lacking the closest ortholog of theEscherichia colihistone-like nucleoid structuring protein (H-NS) but not in mutants with deletion of the other four genes encoding H-NS homologs. H-NS binds to the regulatory region ofgcf, further supporting its direct role as a repressor of thegcfpromoter that starts transcription 158 bp upstream of the start codon of its first open reading frame. Thegcfoperon possesses interesting novel traits that open future opportunities to expand our knowledge of the structure, regulation, and function during infection of these important bacterial structures.IMPORTANCEFimbriae are surface bacterial structures implicated in a variety of biological processes. Some have been shown to play a critical role during host colonization and thus in disease. Pathogenic bacteria possess the genetic information for an assortment of fimbriae, but their function and regulation and the interplay between them have not been studied in detail. This work provides new insights into the function and regulation of a novel fimbria called Gcf that is important for early establishment of a successful infection byC. rodentiumin mice, despite being poorly expressed underin vitrogrowth conditions. This discovery offers an opportunity to better understand the individual role and the regulatory mechanisms controlling the expression of specific fimbrial operons that are critical during infection.

scholarly journals A Toxic Environment: a Growing Understanding of How Microbial Communities Affect Escherichia coli O157:H7 Shiga Toxin Expression

2020 ◽  
Vol 86 (24) ◽  
Author(s):  
Erin M. Nawrocki ◽  
Hillary M. Mosso ◽  
Edward G. Dudley
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Microbial Interactions ◽  
Severe Illness ◽  
Content Type ◽  
E Coli ◽  
Wide Range ◽  
Lambdoid Prophage

ABSTRACT Enterohemorrhagic Escherichia coli (EHEC) strains, including E. coli O157:H7, cause severe illness in humans due to the production of Shiga toxin (Stx) and other virulence factors. Because Stx is coregulated with lambdoid prophage induction, its expression is especially susceptible to environmental cues. Infections with Stx-producing E. coli can be difficult to model due to the wide range of disease outcomes: some infections are relatively mild, while others have serious complications. Probiotic organisms, members of the gut microbiome, and organic acids can depress Stx production, in many cases by inhibiting the growth of EHEC strains. On the other hand, the factors currently known to amplify Stx act via their effect on the stx-converting phage. Here, we characterize two interactive mechanisms that increase Stx production by O157:H7 strains: first, direct interactions with phage-susceptible E. coli, and second, indirect amplification by secreted factors. Infection of susceptible strains by the stx-converting phage can expand the Stx-producing population in a human or animal host, and phage infection has been shown to modulate virulence in vitro and in vivo. Acellular factors, particularly colicins and microcins, can kill O157:H7 cells but may also trigger Stx expression in the process. Colicins, microcins, and other bacteriocins have diverse cellular targets, and many such molecules remain uncharacterized. The identification of additional Stx-amplifying microbial interactions will improve our understanding of E. coli O157:H7 infections and help elucidate the intricate regulation of pathogenicity in EHEC strains.

scholarly journals Group A Streptococcus AdcR Regulon Participates in Bacterial Defense against Host-Mediated Zinc Sequestration and Contributes to Virulence

2020 ◽  
Vol 88 (8) ◽  
Author(s):  
Nishanth Makthal ◽  
Hackwon Do ◽  
Brian M. Wendel ◽  
Randall J. Olsen ◽  
John D. Helmann ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Group A Streptococcus ◽  
Zn Deficiency ◽  
Direct Competition ◽  
Mutant Strains ◽  
Genes Encoding ◽  
Group A ◽  
Gas Interactions

ABSTRACT Colonization by pathogenic bacteria depends on their ability to overcome host nutritional defenses and acquire nutrients. The human pathogen group A streptococcus (GAS) encounters the host defense factor calprotectin (CP) during infection. CP inhibits GAS growth in vitro by imposing zinc (Zn) limitation. However, GAS counterstrategies to combat CP-mediated Zn limitation and the in vivo relevance of CP-GAS interactions to bacterial pathogenesis remain unknown. Here, we report that GAS upregulates the AdcR regulon in response to CP-mediated Zn limitation. The AdcR regulon includes genes encoding Zn import (adcABC), Zn sparing (rpsN.2), and Zn scavenging systems (adcAII, phtD, and phtY). Each gene in the AdcR regulon contributes to GAS Zn acquisition and CP resistance. The ΔadcC and ΔrpsN.2 mutant strains were the most susceptible to CP, whereas the ΔadcA, ΔadcAII, and ΔphtD mutant strains displayed less CP sensitivity during growth in vitro. However, the ΔphtY mutant strain did not display an increased CP sensitivity. The varied sensitivity of the mutant strains to CP-mediated Zn limitation suggests distinct roles for individual AdcR regulon genes in GAS Zn acquisition. GAS upregulates the AdcR regulon during necrotizing fasciitis infection in WT mice but not in S100a9−/− mice lacking CP. This suggests that CP induces Zn deficiency in the host. Finally, consistent with the in vitro results, several of the AdcR regulon genes are critical for GAS virulence in WT mice, whereas they are dispensable for virulence in S100a9−/− mice, indicating the direct competition for Zn between CP and proteins encoded by the GAS AdcR regulon during infection.

scholarly journals Nonselective Persistence of a Rickettsia conorii Extrachromosomal Plasmid during Mammalian Infection

2016 ◽  
Vol 84 (3) ◽  
pp. 790-797 ◽  
Author(s):  
Sean P. Riley ◽  
Abigail I. Fish ◽  
Daniel A. Garza ◽  
Kaikhushroo H. Banajee ◽  
Emma K. Harris ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Genetic Manipulation ◽  
Fluorescent Proteins ◽  
Spotted Fever ◽  
Rickettsia Conorii ◽  
Mediterranean Spotted Fever ◽  
Extrachromosomal Dna ◽  
Content Type

Scientific analysis of the genusRickettsiais undergoing a rapid period of change with the emergence of viable genetic tools. The development of these tools for the mutagenesis of pathogenic bacteria will permit forward genetic analysis ofRickettsiapathogenesis. Despite these advances, uncertainty still remains regarding the use of plasmids to study these bacteria inin vivomammalian models of infection, namely, the potential for virulence changes associated with the presence of extrachromosomal DNA and nonselective persistence of plasmids in mammalian models of infection. Here, we describe the transformation ofRickettsia conoriiMalish 7 with the plasmid pRam18dRGA[AmTrCh]. TransformedR. conoriistably maintains this plasmid in infected cell cultures, expresses the encoded fluorescent proteins, and exhibits growth kinetics in cell culture similar to those of nontransformedR. conorii. Using a well-established murine model of fatal Mediterranean spotted fever, we demonstrate thatR. conorii(pRam18dRGA[AmTrCh]) elicits the same fatal outcomes in animals as its untransformed counterpart and, importantly, maintains the plasmid throughout infection in the absence of selective antibiotic pressure. Interestingly, plasmid-transformedR. conoriiwas readily observed both in endothelial cells and within circulating leukocytes. Together, our data demonstrate that the presence of an extrachromosomal DNA element in a pathogenic rickettsial species does not affect eitherin vitroproliferation orin vivoinfectivity in models of disease and that plasmids such as pRam18dRGA[AmTrCh] are valuable tools for the further genetic manipulation of pathogenic rickettsiae.

scholarly journals Role of F1C Fimbriae, Flagella, and Secreted Bacterial Components in the Inhibitory Effect of Probiotic Escherichia coli Nissle 1917 on Atypical Enteropathogenic E. coli Infection

2014 ◽  
Vol 82 (5) ◽  
pp. 1801-1812 ◽  
Author(s):  
Sylvia Kleta ◽  
Marcel Nordhoff ◽  
Karsten Tedin ◽  
Lothar H. Wieler ◽  
Rafal Kolenda ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Molecular Mechanisms ◽  
Inhibitory Effect ◽  
Host Cells ◽  
Single Infection ◽  
Content Type ◽  
E Coli ◽  
Initial Adhesion

ABSTRACTEnteropathogenicEscherichia coli(EPEC) is recognized as an important intestinal pathogen that frequently causes acute and persistent diarrhea in humans and animals. The use of probiotic bacteria to prevent diarrhea is gaining increasing interest. The probioticE. colistrain Nissle 1917 (EcN) is known to be effective in the treatment of several gastrointestinal disorders. While bothin vitroandin vivostudies have described strong inhibitory effects of EcN on enteropathogenic bacteria, including pathogenicE. coli, the underlying molecular mechanisms remain largely unknown. In this study, we examined the inhibitory effect of EcN on infections of porcine intestinal epithelial cells with atypical enteropathogenicE. coli(aEPEC) with respect to single infection steps, including adhesion, microcolony formation, and the attaching and effacing phenotype. We show that EcN drastically reduced the infection efficiencies of aEPEC by inhibiting bacterial adhesion and growth of microcolonies, but not the attaching and effacing of adherent bacteria. The inhibitory effect correlated with EcN adhesion capacities and was predominantly mediated by F1C fimbriae, but also by H1 flagella, which served as bridges between EcN cells. Furthermore, EcN seemed to interfere with the initial adhesion of aEPEC to host cells by secretion of inhibitory components. These components do not appear to be specific to EcN, but we propose that the strong adhesion capacities enable EcN to secrete sufficient local concentrations of the inhibitory factors. The results of this study are consistent with a mode of action whereby EcN inhibits secretion of virulence-associated proteins of EPEC, but not their expression.

scholarly journals The HtrA-Like Protease CD3284 Modulates Virulence of Clostridium difficile

2014 ◽  
Vol 82 (10) ◽  
pp. 4222-4232 ◽  
Author(s):  
Dennis Bakker ◽  
Anthony M. Buckley ◽  
Anne de Jong ◽  
Vincent J. C. van Winden ◽  
Joost P. A. Verhoeks ◽  
...  
Keyword(s):  
Clostridium Difficile ◽  
Virulence Factors ◽  
Pathogenic Bacteria ◽  
Microarray Data Analysis ◽  
Toxin A ◽  
Hamster Model ◽  
Golden Syrian Hamster ◽  
Content Type

ABSTRACTIn the past decade,Clostridium difficilehas emerged as an important gut pathogen. Symptoms ofC. difficileinfection range from mild diarrhea to pseudomembranous colitis. Besides the two main virulence factors toxin A and toxin B, other virulence factors are likely to play a role in the pathogenesis of the disease. In other Gram-positive and Gram-negative pathogenic bacteria, conserved high-temperature requirement A (HtrA)-like proteases have been shown to have a role in protein homeostasis and quality control. This affects the functionality of virulence factors and the resistance of bacteria to (host-induced) environmental stresses. We found that theC. difficile630 genome encodes a single HtrA-like protease (CD3284; HtrA) and have analyzed its rolein vivoandin vitrothrough the creation of an isogenic ClosTron-basedhtrAmutant ofC. difficilestrain 630Δerm(wild type). In contrast to the attenuated phenotype seen withhtrAdeletion in other pathogens, this mutant showed enhanced virulence in the Golden Syrian hamster model of acuteC. difficileinfection. Microarray data analysis showed a pleiotropic effect ofhtrAon the transcriptome ofC. difficile, including upregulation of the toxin A gene. In addition,the htrAmutant showed reduced spore formation and adherence to colonic cells. Together, our data show thathtrAcan modulate virulence inC. difficile.

scholarly journals The Tat Substrate SufI Is Critical for the Ability of Yersinia pseudotuberculosis To Cause Systemic Infection

2017 ◽  
Vol 85 (4) ◽  
Author(s):  
Ummehan Avican ◽  
Tugrul Doruk ◽  
Yngve Östberg ◽  
Anna Fahlgren ◽  
Åke Forsberg
Keyword(s):  
Stress Responses ◽  
Pathogenic Bacteria ◽  
Yersinia Pseudotuberculosis ◽  
Systemic Infection ◽  
Mesenteric Lymph Nodes ◽  
Content Type ◽  
Twin Arginine Translocation ◽  
Genes Encoding ◽  
Folded Proteins

ABSTRACT The twin arginine translocation (Tat) system targets folded proteins across the inner membrane and is crucial for virulence in many important human-pathogenic bacteria. Tat has been shown to be required for the virulence of Yersinia pseudotuberculosis, and we recently showed that the system is critical for different virulence-related stress responses as well as for iron uptake. In this study, we wanted to address the role of the Tat substrates in in vivo virulence. Therefore, 22 genes encoding potential Tat substrates were mutated, and each mutant was evaluated in a competitive oral infection of mice. Interestingly, a ΔsufI mutant was essentially as attenuated for virulence as the Tat-deficient strain. We also verified that SufI was Tat dependent for membrane/periplasmic localization in Y. pseudotuberculosis. In vivo bioluminescent imaging of orally infected mice revealed that both the ΔsufI and ΔtatC mutants were able to colonize the cecum and Peyer's patches (PPs) and could spread to the mesenteric lymph nodes (MLNs). Importantly, at this point, neither the ΔtatC mutant nor the ΔsufI mutant was able to spread systemically, and they were gradually cleared. Immunostaining of MLNs revealed that both the ΔtatC and ΔsufI mutants were unable to spread from the initial infection foci and appeared to be contained by neutrophils, while wild-type bacteria readily spread to establish multiple foci from day 3 postinfection. Our results show that SufI alone is required for the establishment of systemic infection and is the major cause of the attenuation of the ΔtatC mutant.

Sign in / Sign up

Export Citation Format

Share Document