PROPERTIES OF A BACTERIOPHAGE DERIVED FROM ESCHERICHIA COLI K235

A temperate bacteriophage was isolated from the colicinogenic strain of Escherichia coli K235 and characterized. This phage, termed PK, is related to P2 virus morphologically, serologically, and, possibly, genetically and it bears no relationship to the T-even phages. It was also demonstrated that PK virus and colicine K differ both in their host range and in their immunological specificity, and that PK prophage does not induce the colicinogenesis in its host bacterium. It was concluded that the formation of colicine K. and PK phage in E. coli K235 are controlled by different genetic determinants.

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Silent Mischief: Bacteriophage Mu Insertions Contaminate Products of Escherichia coli Random Mutagenesis Performed Using Suicidal Transposon Delivery Plasmids Mobilized by Broad-Host-Range RP4 Conjugative Machinery

Journal of Bacteriology ◽

10.1128/jb.00621-10 ◽

2010 ◽

Vol 192 (24) ◽

pp. 6418-6427 ◽

Cited By ~ 132

Author(s):

Lionel Ferrières ◽

Gaëlle Hémery ◽

Toan Nham ◽

Anne-Marie Guérout ◽

Didier Mazel ◽

...

Keyword(s):

Escherichia Coli ◽

Host Range ◽

Random Mutagenesis ◽

Broad Host Range ◽

Donor Strain ◽

Bacteriophage Mu ◽

Genetic Determinants ◽

Sensitive Species ◽

E Coli ◽

Original Construction

ABSTRACT Random transposon mutagenesis is the strategy of choice for associating a phenotype with its unknown genetic determinants. It is generally performed by mobilization of a conditionally replicating vector delivering transposons to recipient cells using broad-host-range RP4 conjugative machinery carried by the donor strain. In the present study, we demonstrate that bacteriophage Mu, which was deliberately introduced during the original construction of the widely used donor strains SM10 λpir and S17-1 λpir, is silently transferred to Escherichia coli recipient cells at high frequency, both by hfr and by release of Mu particles by the donor strain. Our findings suggest that bacteriophage Mu could have contaminated many random-mutagenesis experiments performed on Mu-sensitive species with these popular donor strains, leading to potential misinterpretation of the transposon mutant phenotype and therefore perturbing analysis of mutant screens. To circumvent this problem, we precisely mapped Mu insertions in SM10 λpir and S17-1 λpir and constructed a new Mu-free donor strain, MFDpir, harboring stable hfr-deficient RP4 conjugative functions and sustaining replication of Π-dependent suicide vectors. This strain can therefore be used with most of the available transposon-delivering plasmids and should enable more efficient and easy-to-analyze mutant hunts in E. coli and other Mu-sensitive RP4 host bacteria.

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Isolation, characterization and efficacy of lytic bacteriophages against pathogenic Escherichia coli from hospital liquid waste

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d210745 ◽

2020 ◽

Vol 21 (7) ◽

Author(s):

Rahmad Lingga ◽

Sri Budiarti ◽

Iman Rusmana ◽

Aris Tri Wahyudi

Keyword(s):

Escherichia Coli ◽

Host Range ◽

Liquid Waste ◽

Resistant Bacteria ◽

Lytic Bacteriophage ◽

Hospital Wastewater ◽

Electron Micrograph ◽

E Coli ◽

Pathogenic Escherichia Coli ◽

Phage Treatment

Abstract. Lingga R, Budiarti S, Rusmana I, Wahyu AT. 2020. Isolation, characterization and efficacy of lytic bacteriophages against pathogenic Escherichia coli from hospital liquid waste. Biodiversitas 21: 3234-3241. Escherichia coli is known as a pathogenic contaminant bacteria in hospital wastewater hazardous to humans and the environment. Concerns about the emergence of chlorine- and antibiotic-resistant bacteria increase the urgency to find an alternative strategy to control pathogenic bacteria in hospital wastewater. One of the alternatives is using lytic bacteriophage. This study aimed to isolate, characterize, and examine the efficacy of lytic bacteriophage against pathogenic Escherichia coli from hospital wastewater. It isolated, characterized (plaque morphology, host range, virion electron micrograph, and sensitivity to temperature, pH, and chlorine treatments), and tested the efficacy of lytic bacteriophages in controlling pathogenic E. coli isolated from hospital wastewater. Five phages were successfully obtained, all of which had clear plaques (lytic phage character). Based on host range assay, most of the phages could lyse all tested E. coli strains but not for other species. Electron micrograph photography revealed that the phages belonged to Myoviridae. The phages showed stability in high temperature, broad-ranged pH, and high concentrations of chlorine treatments. Assay on phages efficacy suggested that the phages are capable of significantly reducing the E. coli population both in sterilized and non-sterilized wastewater. The combination of phage treatment and chlorine was more effective than single phage treatment. The efficacy test revealed that phage application in wastewater had the best result seen from cocktail treatment and a combination of phage treatment and chlorine. These results suggested that the phage can be a potential candidate for disinfection purposes.

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Transmission of genetic determinants of a heterogeneic antigen similar to human type O (H) antigen from Escherichia coli O55 to E. coli K12 in mice

Bulletin of Experimental Biology and Medicine ◽

10.1007/bf00787563 ◽

1973 ◽

Vol 76 (6) ◽

pp. 1462-1463

Author(s):

A. P. Pekhov ◽

G. M. Bochko ◽

N. I. Rybakov ◽

V. P. Shchipkov ◽

N. I. Buyanova

Keyword(s):

Escherichia Coli ◽

Genetic Determinants ◽

E Coli ◽

Human Type

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Characterization of the β-lactamase specified by the resistance factor R-1818 in Escherichia coli K12 and other Gram-negative bacteria

Biochemical Journal ◽

10.1042/bj1230501 ◽

1971 ◽

Vol 123 (4) ◽

pp. 501-505 ◽

Cited By ~ 13

Author(s):

J. W. Dale

Keyword(s):

Escherichia Coli ◽

Host Species ◽

Host Bacterium ◽

Gram Negative Bacteria ◽

Gram Negative ◽

E Coli ◽

R Factor ◽

Relationship Of ◽

The Relationship

1. The amino acid composition of the β-lactamase from E. coli (R-1818) was determined. 2. The R-1818 β-lactamase is inhibited by formaldehyde, hydroxylamine, sodium azide, iodoacetamide, iodine and sodium chloride. 3. The Km values for benzylpenicillin, ampicillin and oxacillin have been determined by using the R-factor enzyme from different host species. The same values were obtained, irrespective of the host bacterium. 4. The molecular weight of the enzyme was found to be 44600, and was the same for all host species. 5. The relationship of R-1818 and R-GN238 β-lactamases is discussed.

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Genetic Determinants of Resistance to Extended-Spectrum Cephalosporin and Fluoroquinolone in Escherichia coli Isolated from Diseased Pigs in the United States

mSphere ◽

10.1128/msphere.00990-20 ◽

2020 ◽

Vol 5 (5) ◽

Author(s):

Shivdeep Singh Hayer ◽

Seunghyun Lim ◽

Samuel Hong ◽

Ehud Elnekave ◽

Timothy Johnson ◽

...

Keyword(s):

United States ◽

Escherichia Coli ◽

High Risk ◽

The United States ◽

Genetic Determinants ◽

Content Type ◽

E Coli ◽

Extended Spectrum ◽

Animal Populations ◽

Swine Population

ABSTRACT Fluoroquinolones and cephalosporins are critically important antimicrobial classes for both human and veterinary medicine. We previously found a drastic increase in enrofloxacin resistance in clinical Escherichia coli isolates collected from diseased pigs from the United States over 10 years (2006 to 2016). However, the genetic determinants responsible for this increase have yet to be determined. The aim of the present study was to identify and characterize the genetic basis of resistance against fluoroquinolones (enrofloxacin) and extended-spectrum cephalosporins (ceftiofur) in swine E. coli isolates using whole-genome sequencing (WGS). blaCMY-2 (carried by IncA/C2, IncI1, and IncI2 plasmids), blaCTX-M (carried by IncF, IncHI2, and IncN plasmids), and blaSHV-12 (carried by IncHI2 plasmids) genes were present in 87 (82.1%), 19 (17.9%), and 3 (2.83%) of the 106 ceftiofur-resistant isolates, respectively. Of the 110 enrofloxacin-resistant isolates, 90 (81.8%) had chromosomal mutations in gyrA, gyrB, parA, and parC genes. Plasmid-mediated quinolone resistance genes [qnrB77, qnrB2, qnrS1, qnrS2, and aac-(6)-lb′-cr] borne on ColE, IncQ2, IncN, IncF, and IncHI2 plasmids were present in 24 (21.8%) of the enrofloxacin-resistant isolates. Virulent IncF plasmids present in swine E. coli isolates were highly similar to epidemic plasmids identified globally. High-risk E. coli clones, such as ST744, ST457, ST131, ST69, ST10, ST73, ST410, ST12, ST127, ST167, ST58, ST88, ST617, ST23, etc., were also found in the U.S. swine population. Additionally, the colistin resistance gene (mcr-9) was present in several isolates. This study adds valuable information regarding resistance to critical antimicrobials with implications for both animal and human health. IMPORTANCE Understanding the genetic mechanisms conferring resistance is critical to design informed control and preventive measures, particularly when involving critically important antimicrobial classes such as extended-spectrum cephalosporins and fluoroquinolones. The genetic determinants of extended-spectrum cephalosporin and fluoroquinolone resistance were highly diverse, with multiple plasmids, insertion sequences, and genes playing key roles in mediating resistance in swine Escherichia coli. Plasmids assembled in this study are known to be disseminated globally in both human and animal populations and environmental samples, and E. coli in pigs might be part of a global reservoir of key antimicrobial resistance (AMR) elements. Virulent plasmids found in this study have been shown to confer fitness advantages to pathogenic E. coli strains. The presence of international, high-risk zoonotic clones provides worrisome evidence that resistance in swine isolates may have indirect public health implications, and the swine population as a reservoir for these high-risk clones should be continuously monitored.

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Characterization of Multidrug-Resistant Escherichia coli Isolates from Animals Presenting at a University Veterinary Hospital

Applied and Environmental Microbiology ◽

10.1128/aem.00599-11 ◽

2011 ◽

Vol 77 (20) ◽

pp. 7104-7112 ◽

Cited By ~ 59

Author(s):

Maria Karczmarczyk ◽

Yvonne Abbott ◽

Ciara Walsh ◽

Nola Leonard ◽

Séamus Fanning

Keyword(s):

Escherichia Coli ◽

Molecular Mechanisms ◽

Gene Array ◽

Multidrug Resistant ◽

Genetic Determinants ◽

Gene Encoding ◽

Content Type ◽

E Coli ◽

Class 1

ABSTRACTIn this study, we examined molecular mechanisms associated with multidrug resistance (MDR) in a collection ofEscherichia coliisolates recovered from hospitalized animals in Ireland. PCR and DNA sequencing were used to identify genes associated with resistance. Class 1 integrons were prevalent (94.6%) and contained gene cassettes recognized previously and implicated mainly in resistance to aminoglycosides, β-lactams, and trimethoprim (aadA1,dfrA1-aadA1,dfrA17-aadA5,dfrA12-orfF-aadA2,blaOXA-30-aadA1,aacC1-orf1-orf2-aadA1,dfr7). Class 2 integrons (13.5%) contained thedfrA1-sat1-aadA1gene array. The most frequently occurring phenotypes included resistance to ampicillin (97.3%), chloramphenicol (75.4%), florfenicol (40.5%), gentamicin (54%), neomycin (43.2%), streptomycin (97.3%), sulfonamide (98.6%), and tetracycline (100%). The associated resistance determinants detected includedblaTEM,cat,floR,aadB,aphA1,strA-strB,sul2, andtet(B), respectively. TheblaCTX-M-2gene, encoding an extended-spectrum β-lactamase (ESβL), andblaCMY-2, encoding an AmpC-like enzyme, were identified in 8 and 18 isolates, respectively. The mobility of the resistance genes was demonstrated using conjugation assays with a representative selection of isolates. High-molecular-weight plasmids were found to be responsible for resistance to multiple antimicrobial compounds. The study demonstrated that animal-associated commensalE. coliisolates possess a diverse repertoire of transferable genetic determinants. Emergence of ESβLs and AmpC-like enzymes is particularly significant. To our knowledge, theblaCTX-M-2gene has not previously been reported in Ireland.

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Adaptation in a Mouse Colony Monoassociated with Escherichia coli K-12 for More than 1,000 Days

Applied and Environmental Microbiology ◽

10.1128/aem.00358-10 ◽

2010 ◽

Vol 76 (14) ◽

pp. 4655-4663 ◽

Cited By ~ 13

Author(s):

Sean M. Lee ◽

Aaron Wyse ◽

Aaron Lesher ◽

Mary Lou Everett ◽

Linda Lou ◽

...

Keyword(s):

Escherichia Coli ◽

Growth Rates ◽

Bacterial Species ◽

Intestinal Flora ◽

Average Density ◽

Host Bacterium ◽

E Coli ◽

K 12

ABSTRACT Although mice associated with a single bacterial species have been used to provide a simple model for analysis of host-bacteria relationships, bacteria have been shown to display adaptability when grown in a variety of novel environments. In this study, changes associated with the host-bacterium relationship in mice monoassociated with Escherichia coli K-12 over a period of 1,031 days were evaluated. After 80 days, phenotypic diversification of E. coli was observed, with the colonizing bacteria having a broader distribution of growth rates in the laboratory than the parent E. coli. After 1,031 days, which included three generations of mice and an estimated 20,000 generations of E. coli, the initially homogeneous bacteria colonizing the mice had evolved to have widely different growth rates on agar, a potential decrease in tendency for spontaneous lysis in vivo, and an increased tendency for spontaneous lysis in vitro. Importantly, mice at the end of the experiment were colonized at an average density of bacteria that was more than 3-fold greater than mice colonized on day 80. Evaluation of selected isolates on day 1,031 revealed unique restriction endonuclease patterns and differences between isolates in expression of more than 10% of the proteins identified by two-dimensional electrophoresis, suggesting complex changes underlying the evolution of diversity during the experiment. These results suggest that monoassociated mice might be used as a tool for characterizing niches occupied by the intestinal flora and potentially as a method of targeting the evolution of bacteria for applications in biotechnology.

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Different impacts of naturally occurring variants of the globally disseminated carbapenemase-encoding plasmid pKpQIL on the biology of host strains

10.1101/495986 ◽

2018 ◽

Author(s):

Howard T. H. Saw ◽

Mark A. Webber ◽

Neil Woodford ◽

Laura J. V. Piddock

Keyword(s):

Escherichia Coli ◽

Klebsiella Pneumoniae ◽

Host Range ◽

Generation Time ◽

Enterobacter Cloacae ◽

Bacterial Host ◽

E Coli ◽

Naturally Occurring ◽

Filter Mating ◽

Host Strains

SynopsisKlebsiella-associated plasmid pKpQIL and its variant have been isolated globally. Our study aimed to determine whether a naturally occurring variant has altered host range and impacts on the fitness of different bacterial host strains. The plasmids pKpQIL-UK and pKpQIL-D2 were transferred from the original clinical isolate host strains of Klebsiella pneumoniae into Escherichia coli, Salmonella Typhimurium, Enterobacter cloacae and Serratia marcescens strains by filter-mating and conjugation frequencies determined and compared. The fitness of the resulting transconjugants was assessed by determining growth kinetics, ability to form a biofilm and persistence of the plasmids in each host was also measured. Transfer of either plasmid into Salmonella and S. marcescens was similar. However, pKpQIL-UK transferred into E. coli at a higher rate than did pKpQIL-D2; the reverse was found for E. cloacae. Both plasmids were rapidly lost from the E. coli population. Plasmid pKpQIL-UK, but not -D2, was able to persist in Salmonella. Although pKpQIL-UK imposed a greater fitness cost (inferred from an increased generation time) than -D2 on E. cloacae, it was able to persist as well as pKpQIL-D2 in this host. The pKpQIL-D2 plasmid did not confer any fitness benefit on any of the hosts under the conditions tested. Variants of the globally important pKpQIL plasmid have arisen in patients due to recombination. The impacts of the pKpQIL-UK plasmid and the -D2 variant in various Enterobacteriaceae are host-dependent. Continuing evolution of pKpQIL may alter its host range in the future.

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LamB, OmpC, and the Core Lipopolysaccharide of Escherichia coli K-12 Function as Receptors of Bacteriophage Bp7

Journal of Virology ◽

10.1128/jvi.00325-20 ◽

2020 ◽

Vol 94 (12) ◽

Cited By ~ 1

Author(s):

Peipei Chen ◽

Huzhi Sun ◽

Huiying Ren ◽

Wenhua Liu ◽

Guimei Li ◽

...

Keyword(s):

Escherichia Coli ◽

Host Range ◽

Inner Core ◽

Phage Infection ◽

Broad Host Range ◽

Content Type ◽

E Coli ◽

Phage Adsorption ◽

Specific Receptors ◽

K 12

ABSTRACT Bp7 is a T-even phage with a broad host range specific to Escherichia coli, including E. coli K-12. The receptor binding protein (RBP) of bacteriophages plays an important role in the phage adsorption process and determines phage host range, but the molecular mechanism involved in host recognition of phage Bp7 remains unknown. In this study, the interaction between phage Bp7 and E. coli K-12 was investigated. Based on homology alignment, amino acid sequence analysis, and a competitive assay, gp38, located at the tip of the long tail fiber, was identified as the RBP of phage Bp7. Using a combination of in vivo and in vitro approaches, including affinity chromatography, gene knockout mutagenesis, a phage plaque assay, and phage adsorption kinetics analysis, we identified the LamB and OmpC proteins on the surface of E. coli K-12 as specific receptors involved in the first step of reversible phage adsorption. Genomic analysis of the phage-resistant mutant strain E. coli K-12-R and complementation tests indicated that HepI of the inner core of polysaccharide acts as the second receptor recognized by phage Bp7 and is essential for successful phage infection. This observation provides an explanation of the broad host range of phage Bp7 and provides insight into phage-host interactions. IMPORTANCE The RBPs of T4-like phages are gp37 and gp38. The interaction between phage T4 RBP gp37 and its receptors has been clarified by many reports. However, the interaction between gp38 and its receptors during phage adsorption is still not completely understood. Here, we identified phage Bp7, which uses gp38 as an RBP, and provided a good model to study the phage-host interaction mechanisms in an enterobacteriophage. Our study revealed that gp38 of phage Bp7 recognizes the outer membrane proteins (OMPs) LamB and OmpC of E. coli K-12 as specific receptors and binds with them reversibly. HepI of the inner-core oligosaccharide is the second receptor and binds with phage Bp7 irreversibly to begin the infection process. Determining the interaction between the phage and its receptors will help elucidate the mechanisms of phage with a broad host range and help increase understanding of the phage infection mechanism based on gp38.

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Transfer and expression of the genetic determinants for O and K antigen synthesis in Escherichia coli O9:K(A)30 and Klebsiella sp. Ol:K20, in Escherichia coli K12

Canadian Journal of Microbiology ◽

10.1139/m88-173 ◽

1988 ◽

Vol 34 (8) ◽

pp. 987-992 ◽

Cited By ~ 7

Author(s):

Dayle H. Laakso ◽

Mary K. Homonylo ◽

Sheila J. Wilmot ◽

Chris Whitfield

Keyword(s):

Escherichia Coli ◽

Surface Antigens ◽

Capsular Polysaccharides ◽

Genetic Determinants ◽

Cell Surface Antigens ◽

E Coli ◽

Close Proximity ◽

Morphological Differences ◽

Genetically Determined ◽

K Antigen

Escherichia coli serotype O9:K(A)30 and Klebsiella O1:K20 produce thermostable capsular polysaccharides or K antigens, which are chemically and serologically indistinguishable. Plasmid pULB113 (RP4::mini-Mu) has been used to mediate chromosomal transfer from E. coli O9:K30 and Klebsiella O1:K20 to a multiply marked, unencapsulated, E. coli K12 recipient. Analysis of the cell surface antigens of the transconjugants confirmed previous reports that the genetic determinants for the E. coli K(A) antigens are located near the his and rfb (O antigen) loci on the E. coli linkage map. The Klebsiella K20 capsule genes were also found to be in close proximity to the his and rfb loci. Electron microscopy revealed significant differences in the structural organization of capsular polysaccharides in these two microorganisms and the morphological differences were also readily apparent in transconjugants expressing the respective K antigens. These results are consistent with the interpretation that at least some of the organizational properties of capsular polysaccharides may be genetically determined, rather than being a function of the outer membrane to which the capsular polysaccharides are ultimately attached.

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