Allelic types of long polar fimbriae in bovine and human Escherichia coli O157 strains

2012 ◽  
Vol 60 (1) ◽  
pp. 1-15 ◽  
Author(s):  
Domonkos Sváb ◽  
István Tóth
Keyword(s):  
Escherichia Coli ◽  
Escherichia Coli O157 ◽  
Phylogenetic Groups ◽  
Genetic Lineages ◽  
E Coli ◽  
Typing Scheme ◽  
Healthy Cattle ◽  
Reference Collection ◽  
Group D ◽  
Atypical Strains

Long polar fimbriae (Lpf) are recently discovered adhesins and increasingly important genetic markers of pathogenicEscherichia colistrains. The presence and genotype diversity of Lpf operons was screened in a collection of 97Escherichia coliO157 strains representing different pathotypes, isolated from healthy cattle (n = 43) and human patients (n = 54) in several countries. Individual structural genes of Lpf were scanned by PCR, and allelic variants were detected with a recently developed typing scheme. Ninety-five strains carried at least one whole Lpf operon (geneslpfABCDand/orlpfABCDE). The 64 enterohaemorrhagic (EHEC) and 24 enteropathogenic (EPEC) strains all carried two Lpf operons, allele 3 oflpfA1and allele 2 oflpfA2, a combination characteristic of the O157:H7/NM serotype. Out of the 9 bovine atypical (AT;stx-, eae-) strains, 7 carried one complete Lpf operon, allele 1 oflpfA2. The atypical strains belonged to main phylogenetic groups A and B1, while the EHEC and EPEC strains were from group D. Lpf variants carried by the 72 strains of theEscherichia coliReference Collection (ECOR) were determined with the same typing scheme. Alleles were detected in 25 strains, of which 6 were found negative for the respective Lpf operons in earlier studies. The marker value of the Lpf allelic combination for the O157:H7/NM serotype was confirmed, and further evidence was given for the presence of at least two different genetic lineages of atypical bovineE. coliO157 strains.

scholarly journals DiarrheagenicEscherichia coliPhylogroups Are Associated with Antibiotic Resistance and Duration of Diarrheal Episode

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Susan Mosquito ◽  
Maria J. Pons ◽  
Maribel Riveros ◽  
Joaquim Ruiz ◽  
Theresa J. Ochoa
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Clinical Characteristics ◽  
Healthy Controls ◽  
Persistent Diarrhea ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Diarrheal Episode ◽  
Group A ◽  
Group D

Conventionally, inEscherichia coli, phylogenetic groups A and B1 are associated with commensal strains while B2 and D are associated with extraintestinal strains. The aim of this study was to evaluate diarrheagenic (DEC) and commensalE. coliphylogeny and its association with antibiotic resistance and clinical characteristics of the diarrheal episode. Phylogenetic groups and antibiotic resistance of 369E. colistrains (commensal strains and DEC from children with or without diarrhea) isolated from Peruvian children <1 year of age were determined by a Clermont triplex PCR and Kirby-Bauer method, respectively. The distribution of the 369E. colistrains among the 4 phylogenetic groups was A (40%), D (31%), B1 (21%), and B2 (8%). DEC-control strains were more associated with group A while DEC-diarrhea strains were more associated with group D(P<0.05). There was a tendency(P=0.06)for higher proportion of persistent diarrhea (≥14 days) among severe groups (B2 and D) in comparison with nonsevere groups (A and B1). Strains belonging to group D presented significantly higher percentages of multidrug resistance than the rest of the groups(P>0.01). In summary, DEC-diarrhea strains were more associated with group D than strains from healthy controls.

scholarly journals The relationship between phylogenetic groups and antibiotic susceptibility patterns of Escherichia coli strains isolated from feces and urine of patients with acute or recurrent urinary tract infection

2020 ◽  
Author(s):  
Hossein Norouzian ◽  
Mohammad Katouli ◽  
Nader Shahrokhi ◽  
Sharam Sabeti ◽  
Mohammad Pooya ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Diffusion Method ◽  
Multi Drug Resistance ◽  
Resistance Pattern ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Drug Resistance Pattern ◽  
Biochemical Fingerprinting ◽  
Group D

Background and Objectives: B2 and D have been mentioned as the most common phylogenetic groups among uropatho- genic Escherichia coli. However, there is still controversy about the importance of these phylo-groups. This study was con- ducted to investigate the probable relation between these groups and antibiotic resistance patterns of E. coli isolates derived from urine and feces of the patients with acute or recurrent UTI. Materials and Methods: 10 isolates were recovered from urine and feces samples of patients with different phases of UTI in whom E. coli was causative pathogen. Biochemical fingerprinting was performed to classify the isolates and select their appropriate representatives. Phylogenetic grouping was performed using multiplex PCR, and antibiotic resistance was deter- mined by disk diffusion method. Results: Five-hundred-sixty E. coli isolates were derived from 56 UTI patients (27 acute, 29 recurrent). Among them, 261 isolates were selected using biochemical fingerprinting. All the isolates were sensitive to imipenem and nitrofurantoin. Com- pared to other phylo-groups, the isolates in group D showed considerably different frequencies in acute vs. recurrent phase of UTI, in urine vs. stool samples, in males vs. females, and in- vs. out-patients. They were more resistant to the antibiotics (except norfloxacin), and in contrast to others, this was seen more in acute UTI, especially in urine samples. Multi-drug resistance pattern was also meaningfully higher in group D. Conclusion: Although phylo-groups B2 and D of E. coli bacteria are more responsible for UTI, group D isolates seem to be more resistant and probably more virulent, even than the ones from group B2.

scholarly journals Towards discrimination of mammary pathogenic Escherichia coli (MPEC) in cattle based on possession of different iron acquisition systems

2021 ◽  
Author(s):  
Hamideh Kalateh Rahmani ◽  
Gholamreza Hashemi Tabar ◽  
Mahdi Askari Badouei ◽  
Babak Khoramian
Keyword(s):  
Escherichia Coli ◽  
Fairy Tale ◽  
Iron Acquisition ◽  
Growth Potential ◽  
Phylogenetic Groups ◽  
Pathogenic Potential ◽  
Genetic Lineages ◽  
E Coli ◽  
Uht Milk ◽  
Harsh Conditions

AbstractMost efforts to elucidate virulence mechanisms of mammary pathogenic Escherichia coli (MPEC), causative agent of bovine clinical mastitis, have been failed but some recent studies introduced iron acquisition systems as major role players in pathogenicity. Here, we investigated the different iron uptake systems genotypes and assessed how they relate to virulence potential of MPEC. In total, 217 E. coli isolates (MPEC= 157, fecal isolates= 60) were screened for the presence of nine genes related to iron acquisition (iroN, iutA, fecA, fyuA, sitA, irp2, iucD, chuA and tonB) and phylogenetic groups were also determined. Next, bacterial growth potential and survival in raw and UHT milk which are representative for crucial steps in mastitis development were evaluated. In addition, the mineral consumption of E. coli cultured in milk were measured. The results showed that MPEC strains considerably tend to possess fecA (93%, p= 0.000) and belong to phylogenetic group A (42%, p= 0.042). The fecA+ strains from both mastitis and fecal E. coli had a significant (p= 0.000) growth potential in raw and UHT milk. Interestingly, for the first time, it was shown that fecA+ isolates consumed less amounts of iron and other metal ions. Overall, it seems that the uptake systems related to fecA contributes to overcoming harsh conditions of milk and genetic lineages could also affect pathogenicity of MPEC. These findings could lead us to define MPEC with more clarity based on genotypes or growth potential in milk and possibly promote novel solutions to control mastitis more effectively in future.ImportanceMastitis is one of the most costly concerns in bovine medicine and the main cause of antibiotic use in dairy herds’ worldwide. As a rule of thumb, it was believed that extraintestinal pathogenic E. coli expands iron acquisition virulence arsenal to enhance pathogenic potential in the environments of the host outside the intestines. The present study indicated that the long believed idea of possession of diverse mineral acquisition systems and siderophores in all ExPEC groups could be a fairy tale. Along with recent studies, the present research showed that the fec operon could be the minimal necessary factor to overcome the harsh conditions of milk with limiting mineral concentrations. Obviously, the fecA+ isolates were fast-growing and consumed less amounts of minerals. It seems that the fec locus and its related metabolic pathways could be the potential targets for diagnostic, preventive, and therapeutic purposes.

scholarly journals Differences of virulence factors, and antimicrobial susceptibility according to phylogenetic group in uropathogenic Escherichia coli strains isolated from Korean patients

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Miri Hyun ◽  
Ji Yeon Lee ◽  
Hyun ah Kim
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Virulence Factors ◽  
Phylogenetic Group ◽  
Healthcare Associated Infections ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Healthcare Associated ◽  
Genotypic Characteristics ◽  
Group D

Abstract Background Escherichia coli is among the most common uropathogens. Increased antibiotic resistance in Gram negative bacilli is global concern. Alternative therapeutic options including vaccines against uropathogenic E. coli (UPEC) have been developed. In this study, we compared the genotypic characteristics and antimicrobial susceptibility of UPEC according to phylogenetic groups. Methods We retrospectively reviewed the medical records of pyelonephritis patients with UPEC between February 2015 and June 2018. The study was conducted at a medical center in Korea. We compared the clinical and genotypic characteristics of UPEC according to phylogenetic groups. The phylogenetic groups and 29 virulence factors were identified using multiplex polymerase chain reaction. Results Phylogenetic group analysis revealed that most uropathogenic E. coli belonged to groups B2 and D: B2 (276, 77.7%), D (62, 17.5%), B1 (12, 3.4%), and A (5, 1.4%). Among the virulence factors, fyuA, fimH, traT, iutA, papG allele II, and papC were the most frequently observed. Phylogenetic group B2 was more closely related to virulence factors, including fimH, sfa/focED, focG, hlyA, cnf1, fyuA, and PAI, than group D. Groups B2 and D showed similar clinical presentations and complications. Group B2 had mostly healthcare-associated infections and antimicrobial resistance. Group D mostly had community-acquired infections. The K1 serotype was prevalent in group B2, and K5 was the most prevalent in group D. Conclusions Phylogenetic group B2 had more proportions and types of virulence factors than group D. Group B2 showed a high presentation of virulence factors related to adhesions and toxins. An increased presentation of antimicrobial resistance and healthcare-associated infections was also noted. Considering the genetic characteristics of UPEC, alternative therapeutic options targeting frequent virulence factors might be considered in addition to antibiotics.

scholarly journals Distribution of Core Oligosaccharide Types in Lipopolysaccharides from Escherichia coli

2000 ◽  
Vol 68 (3) ◽  
pp. 1116-1124 ◽  
Author(s):  
Karen Amor ◽  
David E. Heinrichs ◽  
Emilisa Frirdich ◽  
Kim Ziebell ◽  
Roger P. Johnson ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Core Oligosaccharide ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Biosynthesis Gene ◽  
Group A ◽  
The Common ◽  
K 12 ◽  
Group D

ABSTRACT In the lipopolysaccharides of Escherichia coli there are five distinct core oligosaccharide (core OS) structures, designated K-12 and R1 to R4. The objective of this work was to determine the prevalences of these core OS types within the species. Unique sequences in the waa (core OS biosynthesis) gene operon were used to develop a PCR-based system that facilitated unequivocal determination of the core OS types in isolates of E. coli. This system was applied to the 72 isolates in the E. coli ECOR collection, a compilation of isolates that is considered to be broadly representative of the genetic diversity of the species. Fifty (69.4%) of the ECOR isolates contained the R1 core OS, 8 (11.1%) were representatives of R2, 8 (11.1%) were R3, 2 (2.8%) were R4, and only 4 (5.6%) were K-12. R1 is the only core OS type found in all four major phylogenetic groups (A, B1, B2, and D) in the ECOR collection. Virulent extraintestinal pathogenic E. coli isolates tend to be closely related to group B2 and, to a lesser extent, group D isolates. All of the ECOR representatives from the B2 and D groups had the R1 core OS. In contrast, commensal E. coli isolates are more closely related to group A, which contains isolates representing each of the five core OS structures. R3 was the only core OS type found in 38 verotoxigenic E. coli (VTEC) isolates from humans and cattle belonging to the common enterohemorrhagic E. coliserogroups O157, O111, and O26. Although isolates from other VTEC serogroups showed more core OS diversity, the R3 type (83.1% of all VTEC isolates) was still predominant. When non-VTEC commensal isolates from cattle were analyzed, it was found that most possessed the R1 core OS type.

scholarly journals Differences of Virulence Factors, And Antimicrobial Susceptibility According To Phylogenetic Group In Uropathogenic Escherichia Coli Strains Isolated From Korean Patients

2021 ◽  
Author(s):  
Miri Hyun ◽  
Ji Yeon Lee ◽  
Hyun Ah Kim
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Virulence Factors ◽  
Phylogenetic Group ◽  
Healthcare Associated Infections ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Healthcare Associated ◽  
Genotypic Characteristics ◽  
Group D

Abstract Background: Escherichia coli is among the most common uropathogens. Increased antibiotic resistance to gram negative bacilli is global concern. Alternative therapeutic options including vaccines against uropathogenic E. coli (UPEC) have been developed. In this study, we compared the genotypic characteristics and antimicrobial susceptibility of UPEC according to phylogenetic groups. Methods: We retrospectively reviewed the medical records of pyelonephritis patients with UPEC between February 2015 and June 2018. We compared the clinical and genotypic characteristics of UPEC according to phylogenetic groups. The phylogenetic groups and 29 virulence factors were identified using multiplex polymerase chain reaction.Results: Phylogenetic group analysis revealed that most uropathogenic E. coli belonged to groups B2 and D: B2 (276, 77.7%), D (62, 17.5%), B1 (12, 3.4%), and A (5, 1.4%). Among the virulence factors, fyuA, fimH, traT, iutA, papG allele II, and papC were the most frequently observed. Phylogenetic group B2 was more closely related to virulence factors, including fimH, sfa/focED, focG, hlyA, cnf1, fyuA, and PAI, than group D. Groups B2 and D showed similar clinical presentations and complications. Group B2 had mostly healthcare-associated infections and antimicrobial resistance. Group D mostly had community-acquired infections. The K1 serotype was prevalent in group B2, and K5 was the most prevalent in group D.Conclusions: Phylogenetic group B2 had more proportions and types of virulence factors than group D. Group B2 showed a high presentation of virulence factors related to adhesions and toxins. An increased presentation of antimicrobial resistance and healthcare-associated infections was also noted. Considering the genetic characteristics of UPEC, alternative therapeutic options targeting frequent virulence factors might be considered in addition to antibiotics.

Fecal Shedding of Escherichia coli O157, Salmonella, and Campylobacter in Swiss Cattle at Slaughter

2004 ◽  
Vol 67 (4) ◽  
pp. 679-684 ◽  
Author(s):  
H. AL-SAIGH ◽  
C. ZWEIFEL ◽  
J. BLANCO ◽  
J. E. BLANCO ◽  
M. BLANCO ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Nalidixic Acid ◽  
Escherichia Coli O157 ◽  
Strongly Correlated ◽  
Crucial Importance ◽  
Fecal Samples ◽  
Fecal Shedding ◽  
E Coli ◽  
Healthy Cattle ◽  
Carcass Contamination

Fecal samples from 2,930 slaughtered healthy cattle were examined with the following goals: (i) to monitor the shedding of Escherichia coli O157, Salmonella, and Campylobacter in cattle; and (ii) to further characterize the isolated strains. The percentage of the 2,930 samples that tested positive for E. coli O157 by PCR was 1.6%. Thirty-eight strains from different animals that agglutinated with Wellcolex E. coli O157 were isolated. Of the six sorbitol-negative strains, five tested positive for stx2 genes (two times for stx2c and three times for stx2), and one strain tested positive for stx1 and stx2c genes. All sorbitol-negative strains belonged to the serotypes O157:H− and O157:H7 and harbored the eae type γ1 and ehxA genes. The 32 sorbitol-positive strains tested negative for stx genes and belonged to the serotypes O157:H2, O157:H7, O157:H8, O157: H12, O157:H19, O157:H25, O157:H27, O157:H38, O157:H43, O157:H45, and O157:H−. All O157:H45 strains harbored the eae subtype α1 and therefore seem to be atypical enteropathogenic E. coli strains. Whereas none of 1,000 examined samples was positive for Salmonella, 95 of 935 (10.2%) samples were positive for Campylobacter, and all strains were identified as C. jejuni. Sixteen Campylobacter strains were resistant to tetracycline, five were resistant to nalidixic acid/ciprofloxacin, four were resistant to streptomycin, and one was resistant to nalidixic acid/ciprofloxacin and streptomycin. Fecal shedding of zoonotic pathogens in slaughter animals is strongly correlated with the hazard of carcass contamination. Therefore, the maintenance of slaughter hygiene is of crucial importance.

scholarly journals Lineage and Host Source Are Both Correlated with Levels of Shiga Toxin 2 Production by Escherichia coli O157:H7 Strains

2009 ◽  
Vol 76 (2) ◽  
pp. 474-482 ◽  
Author(s):  
Yongxiang Zhang ◽  
Chad Laing ◽  
Zhengzhong Zhang ◽  
Jennyka Hallewell ◽  
Chunping You ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Enzyme Linked Immunosorbent Assay ◽  
Escherichia Coli O157 ◽  
Rt Pcr ◽  
Genetic Lineages ◽  
E Coli ◽  
Shiga Toxin 2 ◽  
Flanking Region ◽  
Q Gene

ABSTRACT Escherichia coli O157:H7 strains fall into three major genetic lineages that differ in their distribution among humans and cattle. Several recent studies have reported differences in the expression of virulence factors between E. coli O157:H7 strains from these two host species. In this study, we wished to determine if important virulence-associated “mobile genetic elements” such as Shiga toxin 2 (Stx2)-encoding prophage are lineage restricted or are host source related and acquired independently of the pathogen genotype. DNA sequencing of the stx 2 flanking region from a lineage II (LII) strain, EC970520, revealed that the transcriptional activator gene Q in LI strain EDL933 (upstream of stx 2) is replaced by a pphA (serine/threonine phosphatase) homologue and an altered Q gene in this and all other LII strains tested. In addition, nearly all LI strains carried stx 2, whereas all LII strains carried variant stx 2c and 4 of 14 LI/II strains had copies of both stx 2 and variant stx 2c. Real-time PCR (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) demonstrated that LI and LI/II strains produce significantly more stx 2 mRNA and Stx2 than LII strains. However, among LI strains significantly more Stx2 is also produced by strains from humans than from cattle. Therefore, lineage-associated differences among E. coli O157:H7 strains such as prophage content, toxin type, and toxin expression may contribute to host isolation bias. However, the level of Stx2 production alone may also play an important role in the within-lineage association of E. coli O157:H7 strains with human clinical disease.

scholarly journals Prevalence and Persistence of Escherichia coli Strains with Uropathogenic Virulence Characteristics in Sewage Treatment Plants

2010 ◽  
Vol 76 (17) ◽  
pp. 5882-5886 ◽  
Author(s):  
E. M. Anastasi ◽  
B. Matthews ◽  
A. Gundogdu ◽  
T. L. Vollmerhausen ◽  
N. L. Ramos ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Genes ◽  
Sewage Treatment ◽  
Subtropical Region ◽  
Biochemical Phenotype ◽  
Phylogenetic Groups ◽  
Sewage Treatment Plants ◽  
E Coli ◽  
Treatment Processes ◽  
Group D

ABSTRACTWe investigated the prevalence and persistence ofEscherichia colistrains in four sewage treatment plants (STPs) in a subtropical region of Queensland, Australia. In all, 264E. colistrains were typed using a high-resolution biochemical fingerprinting method and grouped into either a single or a common biochemical phenotype (S-BPT and C-BPT, respectively). These strains were also tested for their phylogenetic groups and 12 virulence genes associated with intestinal and extraintestinalE. colistrains. Comparison of BPTs at various treatment stages indicated that certain BPTs were found in two or all treatment stages. These BPTs constituted the highest proportion ofE. colistrains in each STP and belonged mainly to phylogenetic group B2 and, to a lesser extent, group D. No virulence genes associated with intestinalE. coliwere found among the strains, but 157 (59.5%) strains belonging to 14 C-BPTs carried one or more virulence genes associated with uropathogenic strains. Of these, 120 (76.4%) strains belonged to seven persistent C-BPTs and were found in all four STPs. Our results indicate that certain clonal groups ofE. coliwith virulence characteristics of uropathogenic strains can survive the treatment processes of STPs. These strains were common to all STPs and constituted the highest proportion of the strains in different treatment tanks of each STP.

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