A Commensal Gone Bad: Complete Genome Sequence of the Prototypical Enterotoxigenic Escherichia coli Strain H10407

ABSTRACT In most cases, Escherichia coli exists as a harmless commensal organism, but it may on occasion cause intestinal and/or extraintestinal disease. Enterotoxigenic E. coli (ETEC) is the predominant cause of E. coli-mediated diarrhea in the developing world and is responsible for a significant portion of pediatric deaths. In this study, we determined the complete genomic sequence of E. coli H10407, a prototypical strain of enterotoxigenic E. coli, which reproducibly elicits diarrhea in human volunteer studies. We performed genomic and phylogenetic comparisons with other E. coli strains, revealing that the chromosome is closely related to that of the nonpathogenic commensal strain E. coli HS and to those of the laboratory strains E. coli K-12 and C. Furthermore, these analyses demonstrated that there were no chromosomally encoded factors unique to any sequenced ETEC strains. Comparison of the E. coli H10407 plasmids with those from several ETEC strains revealed that the plasmids had a mosaic structure but that several loci were conserved among ETEC strains. This study provides a genetic context for the vast amount of experimental and epidemiological data that have been published.

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The Genome Sequence of Avian Pathogenic Escherichia coli Strain O1:K1:H7 Shares Strong Similarities with Human Extraintestinal Pathogenic E. coli Genomes

Journal of Bacteriology ◽

10.1128/jb.01726-06 ◽

2007 ◽

Vol 189 (8) ◽

pp. 3228-3236 ◽

Cited By ~ 225

Author(s):

Timothy J. Johnson ◽

Subhashinie Kariyawasam ◽

Yvonne Wannemuehler ◽

Paul Mangiamele ◽

Sara J. Johnson ◽

...

Keyword(s):

Escherichia Coli ◽

Genomic Sequence ◽

Epidemiological Studies ◽

Coli Strain ◽

Avian Pathogenic Escherichia Coli ◽

Future Studies ◽

E Coli ◽

Food Borne ◽

Pathogenic Escherichia Coli ◽

Complete Genomic

ABSTRACT Escherichia coli strains that cause disease outside the intestine are known as extraintestinal pathogenic E. coli (ExPEC) and include human uropathogenic E. coli (UPEC) and avian pathogenic E. coli (APEC). Regardless of host of origin, ExPEC strains share many traits. It has been suggested that these commonalities may enable APEC to cause disease in humans. Here, we begin to test the hypothesis that certain APEC strains possess potential to cause human urinary tract infection through virulence genotyping of 1,000 APEC and UPEC strains, generation of the first complete genomic sequence of an APEC (APEC O1:K1:H7) strain, and comparison of this genome to all available human ExPEC genomic sequences. The genomes of APEC O1 and three human UPEC strains were found to be remarkably similar, with only 4.5% of APEC O1's genome not found in other sequenced ExPEC genomes. Also, use of multilocus sequence typing showed that some of the sequenced human ExPEC strains were more like APEC O1 than other human ExPEC strains. This work provides evidence that at least some human and avian ExPEC strains are highly similar to one another, and it supports the possibility that a food-borne link between some APEC and UPEC strains exists. Future studies are necessary to assess the ability of APEC to overcome the hurdles necessary for such a food-borne transmission, and epidemiological studies are required to confirm that such a phenomenon actually occurs.

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Gene Cluster for Assembly of Pilus Colonization Factor Antigen III of Enterotoxigenic Escherichia coli

Infection and Immunity ◽

10.1128/iai.69.9.5864-5873.2001 ◽

2001 ◽

Vol 69 (9) ◽

pp. 5864-5873 ◽

Cited By ~ 33

Author(s):

Tooru Taniguchi ◽

Yukihiro Akeda ◽

Ayako Haba ◽

Yoko Yasuda ◽

Koichiro Yamamoto ◽

...

Keyword(s):

Escherichia Coli ◽

Nucleotide Sequence ◽

Gene Cluster ◽

Enterotoxigenic Escherichia Coli ◽

Human Colon Carcinoma Cell ◽

E Coli ◽

Colonization Factor ◽

Type Iv ◽

K 12 ◽

Factor Antigen

ABSTRACT The assembly of pilus colonization factor antigen III (CFA/III) of enterotoxigenic Escherichia coli (ETEC) requires the processing of CFA/III major pilin (CofA) by a prepilin peptidase (CofP), similar to other type IV pilus formation systems. CofA is produced initially as a 26.5-kDa preform pilin (prepilin) and then processed to a 20.5-kDa mature pilin by CofP which is predicted to be localized in the inner membrane. In the present experiment, we determined the nucleotide sequence of the whole region for CFA/III formation and identified a cluster of 14 genes, includingcofA and cofP. Several proteins encoded bycof genes were similar to previously described proteins, such as the toxin-coregulated pili of Vibrio cholerae and the bundle-forming pili of enteropathogenic E. coli. The G+C content of the cof gene cluster was 37%, which was significantly lower than the average for the E. coli genome (50%). The introduction of a recombinant plasmid containing thecof gene cluster into the E. coli K-12 strain conferred CFA/III biogenesis and the ability of adhesion to the human colon carcinoma cell line Caco-2. This is the first report of a complete nucleotide sequence of the type IV pili found in human ETEC, and our results provide a useful model for studying the molecular mechanism of CFA/III biogenesis and the role of CFA/III in ETEC infection.

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TleA, a Tsh-Like Autotransporter Identified in a Human Enterotoxigenic Escherichia coli Strain

Infection and Immunity ◽

10.1128/iai.02976-14 ◽

2015 ◽

Vol 83 (5) ◽

pp. 1893-1903 ◽

Cited By ~ 8

Author(s):

Daniela Gutiérrez ◽

Mirka Pardo ◽

David Montero ◽

Angel Oñate ◽

Mauricio J. Farfán ◽

...

Keyword(s):

Escherichia Coli ◽

Genomic Library ◽

Coli Strain ◽

Enterotoxigenic Escherichia Coli ◽

Watery Diarrhea ◽

Temperature Sensitive ◽

Content Type ◽

E Coli ◽

Colonization Factor ◽

Adhesion Level

EnterotoxigenicEscherichia coli(ETEC), a leading cause of acute diarrhea, colonizes the intestine by means of adhesins. However, 15 to 50% of clinical isolates are negative for known adhesins, making it difficult to identify antigens for broad-coverage vaccines. The ETEC strain 1766a, obtained from a child with watery diarrhea in Chile, harbors the colonization factor CS23 but is negative for other known adhesins. One clone, derived from an ETEC 1766a genomic library (clone G10), did not produce CS23 yet was capable of adhering to Caco-2 cells. The goal of this study was to identify the gene responsible for this capacity. Random transposon-based mutagenesis allowed the identification of a 4,110-bp gene that codes for a homologue of the temperature-sensitive hemagglutinin (Tsh) autotransporter described in avianE. colistrains (97% identity, 90% coverage) and that is called TleA (Tsh-like ETEC autotransporter) herein. An isogenic ETEC 1766a strain with atleAmutation showed an adhesion level similar to that of the wild-type strain, suggesting that the gene does not direct attachment to Caco-2 cells. However, expression oftleAconferred the capacity for adherence to nonadherentE. coliHB101. This effect coincided with the detection of TleA on the surface of nonpermeabilized bacteria, while, conversely, ETEC 1766a seems to secrete most of the produced autotransporter to the medium. On the other hand, TleA was capable of degrading bovine submaxillary mucin and leukocyte surface glycoproteins CD45 and P-selectin glycoprotein ligand 1 (PSGL-1). These results suggest that TleA promotes colonization of the intestinal epithelium and that it may modulate the host immune response.

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CS5 Pilus Biosynthesis Genes from Enterotoxigenic Escherichia coli O115:H40

Journal of Bacteriology ◽

10.1128/jb.181.18.5847-5851.1999 ◽

1999 ◽

Vol 181 (18) ◽

pp. 5847-5851 ◽

Cited By ~ 3

Author(s):

Thomas G. Duthy ◽

Lothar H. Staendner ◽

Paul A. Manning ◽

Michael W. Heuzenroeder

Keyword(s):

Escherichia Coli ◽

Dna Sequences ◽

Surface Expression ◽

Open Reading Frames ◽

Enterotoxigenic Escherichia Coli ◽

Cell Surface Expression ◽

E Coli ◽

Pilus Biogenesis ◽

K 12 ◽

And Function

ABSTRACT We have sequenced the entire region of DNA required for the biosynthesis of CS5 pili from enterotoxigenic Escherichia coli O115:H40 downstream of the major subunit gene, designatedcsfA (for coli surface factor five A). Five more open reading frames (ORFs) (csfB, csfC,csfE, csfF, and csfD) which are transcribed in the same direction as the major subunit and are flanked by a number of insertion sequence regions have been identified. T7 polymerase-mediated overexpression of the cloned csf ORFs confirmed protein sizes based on the DNA sequences that encode them. The expression of only the csf region in E. coli K-12 resulted in the hemagglutination of human erythrocytes and the cell surface expression of CS5 pili, suggesting that the cluster contains all necessary information for CS5 pilus biogenesis and function.

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Some Characteristics of the Outer Membrane Material Released by Growing Enterotoxigenic Escherichia coli

Infection and Immunity ◽

10.1128/iai.29.2.704-713.1980 ◽

1980 ◽

Vol 29 (2) ◽

pp. 704-713 ◽

Cited By ~ 1

Author(s):

Henk Gankema ◽

Jan Wensink ◽

Pieter A. M. Guinée ◽

Wim H. Jansen ◽

Bernard Witholt

Keyword(s):

Escherichia Coli ◽

Outer Membrane ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Freeze Fracture ◽

Sucrose Density Gradient ◽

Enterotoxigenic Escherichia Coli ◽

E Coli ◽

Freeze Fracture Electron Microscopy ◽

K 12

The high-molecular-weight material released into the medium by Escherichia coli AP1, an enterotoxigenic strain of porcine origin, has been isolated and resolved into two clearly distinct fractions, based on sucrose density gradient and differential centrifugation, chemical analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and freeze-fracture electron microscopy. These two fractions, referred to as “medium vesicles” and “medium lipopolysaccharides”, were compared with the cellular outer and cytoplasmic membranes, the periplasmic fraction, and the cytoplasmic fraction. The medium vesicles closely resembled outer membrane and accounted for 3 to 5% of the total cellular outer membrane. They contained most of the heat-labile enterotoxin (LT) activity released into the medium by E. coli AP1. The medium lipopolysaccharide consisted mostly of lipopolysaccharide and a small amount of outer membrane and contained relatively little LT activity. Based on experiments with E. coli K-12 strains, in which about 5% of the newly synthesized outer membrane is lost from areas of outer membrane synthesis, it is proposed that enterotoxigenic E. coli strains release LT as part of such newly synthesized outer membrane fragments and that released outer membrane fragments may function as physiologically significant LT carriers.

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The lipopolysaccharide of the mastitis isolate Escherichia coli strain 1303 comprises a novel O-antigen and the rare K-12 core type

Microbiology ◽

10.1099/mic.0.046912-0 ◽

2011 ◽

Vol 157 (6) ◽

pp. 1750-1760 ◽

Cited By ~ 13

Author(s):

Katarzyna A. Duda ◽

Buko Lindner ◽

Helmut Brade ◽

Andreas Leimbach ◽

Elżbieta Brzuszkiewicz ◽

...

Keyword(s):

Escherichia Coli ◽

Inner Core ◽

Bovine Mastitis ◽

Outer Core ◽

Coli Strain ◽

Core Oligosaccharide ◽

2D Nmr Spectroscopy ◽

E Coli ◽

O Antigen ◽

K 12

Mastitis represents one of the most significant health problems of dairy herds. The two major causative agents of this disease are Escherichia coli and Staphylococcus aureus. Of the first, its lipopolysaccharide (LPS) is thought to play a prominent role during infection. Here, we report the O-antigen (OPS, O-specific polysaccharide) structure of the LPS from bovine mastitis isolate E. coli 1303. The structure was determined utilizing chemical analyses, mass spectrometry, and 1D and 2D NMR spectroscopy methods. The O-repeating unit was characterized as -[→4)-β-d-Quip3NAc-(1→3)-α-l-Fucp2OAc-(1→4)-β-d-Galp-(1→3)-α-d-GalpNAc-(1→]- in which the O-acetyl substitution was non-stoichiometric. The nucleotide sequence of the O-antigen gene cluster of E. coli 1303 was also determined. This cluster, located between the gnd and galF genes, contains 13 putative open reading frames, most of which represent unknown nucleotide sequences that have not been described before. The O-antigen of E. coli 1303 was shown to substitute O-7 of the terminal ld-heptose of the K-12 core oligosaccharide. Interestingly, the non-OPS-substituted core oligosaccharide represented a truncated version of the K-12 outer core – namely terminal ld-heptose and glucose were missing; however, it possessed a third Kdo residue in the inner core. On the basis of structural and genetic data we show that the mastitis isolate E. coli 1303 represents a new serotype and possesses the K-12 core type, which is rather uncommon among human and bovine isolates.

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Characterization of the flexible genome complement of the commensal Escherichia coli strain A0 34/86 (O83 : K24 : H31)

Microbiology ◽

10.1099/mic.0.27469-0 ◽

2005 ◽

Vol 151 (2) ◽

pp. 385-398 ◽

Cited By ~ 33

Author(s):

Jana Hejnova ◽

Ulrich Dobrindt ◽

Radka Nemcova ◽

Christophe Rusniok ◽

Alojz Bomba ◽

...

Keyword(s):

Escherichia Coli ◽

Multiplex Pcr ◽

Gene Clusters ◽

Coli Strain ◽

Bac Clone ◽

Sequence Comparisons ◽

Multiple Sequence ◽

E Coli ◽

Gut Colonization ◽

K 12

Colonization by the commensal Escherichia coli strain A0 34/86 (O83 : K24 : H31) has proved to be safe and efficient in the prophylaxis and treatment of nosocomial infections and diarrhoea of preterm and newborn infants in Czech paediatric clinics over the past three decades. In searching for traits contributing to this beneficial effect related to the gut colonization capacity of the strain, the authors have analysed its genome by DNA–DNA hybridization to E. coli K-12 (MG1655) genomic DNA arrays and to ‘Pathoarrays’, as well as by multiplex PCR, bacterial artificial chromosome (BAC) library cloning and shotgun sequencing. Four hundred and ten E. coli K-12 ORFs were absent from A0 34/86, while 72 out of 456 genes associated with pathogenicity islands of E. coli and Shigella were also detected in E. coli A0 34/86. Furthermore, extraintestinal pathogenic E. coli-related genes involved in iron uptake and adhesion were detected by multiplex PCR, and genes encoding the HlyA and cytotoxic necrotizing factor toxins, together with 21 genes of the uropathogenic E. coli 536 pathogenicity island II, were identified by analysis of 2304 shotgun and 1344 BAC clone sequences of A0 34/86 DNA. Multiple sequence comparisons identified 31 kb of DNA specific for E. coli A0 34/86; some of the genes carried by this DNA may prove to be implicated in the colonization capacity of the strain, enabling it to outcompete pathogens. Among 100 examined BAC clones roughly covering the A0 34/86 genome, one reproducibly conferred on the laboratory strain DH10B an enhanced capacity to persist in the intestine of newborn piglets. Sequencing revealed that this BAC clone carried gene clusters encoding gluconate and mannonate metabolism, adhesion (fim), invasion (ibe) and restriction/modification functions. Hence, the genome of this clinically safe and highly efficient colonizer strain appears to harbour many ‘virulence-associated’ genes. These results highlight the thin line between bacterial ‘virulence’ and ‘fitness' or ‘colonization’ factors, and question the definition of enterobacterial virulence factors.

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A SitABCD homologue from an avian pathogenic Escherichia coli strain mediates transport of iron and manganese and resistance to hydrogen peroxide

Microbiology ◽

10.1099/mic.0.28682-0 ◽

2006 ◽

Vol 152 (3) ◽

pp. 745-758 ◽

Cited By ~ 85

Author(s):

Mourad Sabri ◽

Simon Léveillé ◽

Charles M. Dozois

Keyword(s):

Escherichia Coli ◽

Hydrogen Peroxide ◽

Metal Ion ◽

Growth Promotion ◽

Coli Strain ◽

Transport Systems ◽

Virulence Plasmid ◽

E Coli ◽

K 12 ◽

Iron And Manganese

An operon encoding a member of the family of ATP-binding cassette (ABC) divalent metal ion transporters, homologous to Salmonella enterica SitABCD, has been identified in the avian pathogenic Escherichia coli (APEC) strain χ7122. The sitABCD genes were located on the virulence plasmid pAPEC-1, and were highly similar at the nucleotide level to the chromosomally encoded sitABCD genes present in Shigella spp. A cloned copy of sitABCD conferred increased growth upon a siderophore-deficient E. coli strain grown in nutrient broth supplemented with the chelator 2,2′-dipyridyl. Ion rescue demonstrated that Sit-mediated growth promotion of this strain was due to the transport of iron. SitABCD mediated increased transport of both iron and manganese as demonstrated by uptake of 55Fe, 59Fe or 54Mn in E. coli K-12 strains deficient for the transport of iron (aroB feoB) and manganese (mntH) respectively. Isotope uptake and transport inhibition studies showed that in the iron transport deficient strain, SitABCD demonstrated a greater affinity for iron than for manganese, and SitABCD-mediated transport was higher for ferrous iron, whereas in the manganese transport deficient strain, SitABCD demonstrated greater affinity for manganese than for iron. Introduction of the APEC sitABCD genes into an E. coli K-12 mntH mutant also conferred increased resistance to the bactericidal effects of hydrogen peroxide. APEC strain χ7122 derivatives lacking either a functional SitABCD or a functional MntH transport system were as resistant to hydrogen peroxide as the wild-type strain, whereas a Δsit ΔmntH double mutant was more sensitive to hydrogen peroxide. Overall, the results demonstrate that in E. coli SitABCD represents a manganese and iron transporter that, in combination with other ion transport systems, may contribute to acquisition of iron and manganese, and resistance to oxidative stress.

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Complete Genome Sequence ofEscherichia coliER1821R, a Laboratory K-12 Derivative Engineered To Be Deficient in All Methylcytosine and Methyladenine Restriction Systems

Genome Announcements ◽

10.1128/genomea.00763-16 ◽

2016 ◽

Vol 4 (4) ◽

Cited By ~ 2

Author(s):

Michael G. Jobling ◽

Elisabeth A. Raleigh ◽

Daniel N. Frank

Keyword(s):

Escherichia Coli ◽

Complete Genome Sequence ◽

Complete Genome ◽

Genomic Sequence ◽

Laboratory Strain ◽

Complete Genomic Sequence ◽

Immigration Control ◽

K 12 ◽

Methylation Patterns ◽

Complete Genomic

We present here the complete genomic sequence of a rifampin-resistant derivative of theEscherichia coliK-12 laboratory strain ER1821, engineered to be deficient in all known restriction systems, making it suitable for generating unbiased libraries from organisms with non-K-12 methylation patterns. The ER1821R genome is most closely related to that of DH1, another popular cloning strain (both derived from MM294), but is deleted for thee14prophage (McrA-) and the immigration control (McrBC-EcoKI R-M-Mrr-) loci.

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Cloning and expression of the beta-D-phosphogalactoside galactohydrolase gene of Lactobacillus casei in Escherichia coli K-12

Journal of Bacteriology ◽

10.1128/jb.152.3.1138-1146.1982 ◽

1982 ◽

Vol 152 (3) ◽

pp. 1138-1146

Author(s):

L J Lee ◽

J B Hansen ◽

E K Jagusztyn-Krynicka ◽

B M Chassy

Keyword(s):

Escherichia Coli ◽

Lactobacillus Casei ◽

Specific Activity ◽

Protein Product ◽

Coli Strain ◽

Cloning And Expression ◽

E Coli ◽

Lactose Metabolism ◽

Gene Coding ◽

K 12

Lactose metabolism in Lactobacillus casei 64H is associated with the presence of plasmid pLZ64. This plasmid determines both phosphoenolpyruvate-dependent phosphotransferase uptake of lactose and beta-D-phosphogalactoside galactohydrolase. A shotgun clone bank of chimeric plasmids containing restriction enzyme digest fragments of pLZ64 DNA was constructed in Escherichia coli K-12. One clone contained the gene coding for beta-D-phosphogalactoside galactohydrolase on a 7.9-kilobase PstI fragment cloned into the vector pBR322 in E. coli strain chi 1849. The beta-D-phosphogalactoside galactohydrolase enzyme isolated from E. coli showed no difference from that isolated from L. casei, and specific activity of beta-D-phosphogalactoside galactohydrolase was stimulated 1.8-fold in E. coli by growth in media containing beta-galactosides. A restriction map of the recombinant plasmid was compiled, and with that information, a series of subclones was constructed. From an analysis of the proteins produced by minicells prepared from transformant E. coli cells containing each of the recombinant subclone plasmids, it was found that the gene for the 56-kilodalton beta-D-phosphogalactoside galactohydrolase was transcribed from an L. casei-derived promoter. The gene for a second protein product (43 kilodaltons) was transcribed in the opposite direction, presumably under the control of a promoter in pBR322. The relationship of this second product to the lactose metabolism genes of L. casei is at present unknown.

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