scholarly journals Age as a Factor Influencing Diversity of Commensal E. coli Microflora in Pigs

2013 ◽  
Vol 62 (2) ◽  
pp. 165-171 ◽  
Author(s):  
EWA BOK ◽  
JUSTYNA MAZUREK ◽  
PAWEŁ PUSZ ◽  
MICHAŁ STOSIK ◽  
KATARZYNA BALDY-CHUDZIK
Keyword(s):  
Virulence Factors ◽  
Virulence Genes ◽  
Phylogenetic Group ◽  
Pcr Analysis ◽  
Weaned Piglets ◽  
Phylogenetic Groups ◽  
Phylogenetic Structure ◽  
E Coli ◽  
Phylogenetic Grouping ◽  
Group A

Commensal, intestinal E. coli microflora plays a role in maintenance of intestinal balance of the host, is responsible for defending against pathogenic E. coli. This study encompasses the analysis of BOX-PCR fingerprinting patterns, phylogenetic grouping and virulence genes prevalence among commensal E. coli isolates derived from healthy pigs. Altogether, 274 unique E. coli isolates were identified, 110 from weaned piglets (Piglets I and Piglets II) and 164 from adult sows (Sows I and Sows II). BOX-PCR analysis distinguished isolates from pigs in different age and indicated that during maturation the changes in E. coli microflora occurred. Phylogenetic grouping revealed significant differences between distribution of four phylogenetic groups among isolates derived from piglets and sows. In phylogenetic structure of isolates from the piglets group B1 prevailed significantly, while among isolates derived from the sows the majority of them were classified into phylogenetic group A. The identification of 17 virulence factors in E. coli isolates derived from healthy pigs was performed. Three of 13 intestinal (escV, ehxA, estII) and four extra-intestinal virulence genes (VGs) (hlyA, fimH, papA, sfaS) were detected in the porcine isolates. The percentage of VGs positive isolates among piglets is higher than among sows, moreover, the VGs occurring in E. coli isolates from piglets revealed greater diversity than that detected among isolates from sows.

scholarly journals Carbapenem Resistance Profiles of Pathogenic Escherichia coli in Uganda

2021 ◽  
Vol 2 (2) ◽  
pp. 63-73
Author(s):  
Kenneth Ssekatawa ◽  
Denis K. Byarugaba ◽  
Jesca L. Nakavuma ◽  
Charles D. Kato ◽  
Francis Ejobi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Factors ◽  
Virulence Genes ◽  
Carbapenem Resistance ◽  
Phylogenetic Group ◽  
Clinical Isolates ◽  
Phylogenetic Groups ◽  
Phenotypic Resistance ◽  
E Coli ◽  
Tract Infections

Escherichia coli has been implicated as one of the main etiological agents of diarrhea, urinary tract infections, meningitis and septicemia worldwide. The ability to cause diseases is potentiated by presence of virulence factors. The virulence factors influence the capacity of E. coli to infect and colonize different body systems. Thus, pathogenic E. coli are grouped into DEC strains that are mainly clustered in phylogenetic group B1 and A; ExPEC belonging to A, B2 and D. Coexistence of virulence and beta-lactamase encoding genes complicates treatment outcomes. Therefore, this study aimed at presenting the carbapenem resistance (CR) profiles among pathogenic E. coli. This was a retrospective cross-sectional study involving use of 421 archived E. coli clinical isolates collected in 2019 from four Uganda tertiary hospitals. The isolates were subjected to antibiotics sensitivity assays to determine phenotypic resistance. Four sets of multiplex PCR were performed to detect CR genes, DEC pathotypes virulence genes, ExPEC PAI and the E. coli phylogenetic groups. Antibiotic susceptibility revealed that all the 421 E. coli isolates used were MDR as they exhibited 100% resistance to more than one of the first-line antibiotics. The study registered phenotypic and genotypic CR prevalence of 22.8% and 33.0% respectively. The most predominant gene was blaOXA-48 with genotypic frequency of 33.0%, then blaVIM (21.0%), blaIMP (16.5%), blaKPC (14.8%) and blaNDM (14.8%). Spearman’s correlation revealed that presence of CR genes was highly associated with phenotypic resistance. Furthermore, of 421 MDR E. coli isolates, 19.7% harboured DEC virulence genes, where EPEC recorded significantly higher prevalence (10.8%) followed by S-ETEC (3.1%), STEC (2.9%), EIEC (2.0%) and L-ETEC (2.0%). Genetic analysis characterized 46.1% of the isolates as ExPEC and only PAI IV536 (33.0%) and PAI IICFT073 (13.1%) were detected. Phylogenetic group B2 was predominantly detected (41.1%), followed by A (30.2%), B1(21.6%), and D (7.1%). Furthermore, 38.6% and 23.1% of the DEC and ExPEC respectively expressed phenotypic resistance. Our results exhibited significant level of CR carriage among the MDR DEC and ExPEC clinical isolates belonging to phylogenetic groups B1 and B2 respectively. Virulence and CR genetic factors are mainly located on mobile elements. Thus, constitutes a great threat to the healthcare system as this promotes horizontal gene transfer.

scholarly journals A COMPARATIVE STUDY OF SOME VIRULENCE FACTORS AND PHYLOGENETIC CHARACTRIZATION OF Escherichia.coli ISOLATES CAUSING URINARY TRACT INFECTION AND THE COMMENSAL GUT MICROBIOTA

2019 ◽  
Vol 50 (4) ◽  
Author(s):  
Ahmed & et al.
Keyword(s):  
Urinary Tract ◽  
Virulence Factors ◽  
Virulence Genes ◽  
Fecal Samples ◽  
E Coli ◽  
Phylogenetic Grouping ◽  
Group A ◽  
The Common ◽  
Tract Infections ◽  
Hlya Gene

Variety of virulence factors are involved in the pathogenicity of Escherichia coli isolates, the common cause of the urinary tract infections.(UTIs). This study was aimed.to determine some virulence factors.involved in the pathogenicity.and the phylogenetic.grouping of uropathogenic E. coli isolates.from UTIs in compare.with isolates.from gut.microbiota (fecal flora) In.this study ,E coli isolates  were collected from  samples .urine (n = 25), fecal samples (n = 25) samples of  the same patients with UTI, and from fecal samples (n= 5 as control )of patients without UTI. The detection of phylogenetic grouping and some virulence genes among the all isolates were confirmed by PCR technique. The results.showed that.phylogenetic groups B2,B1(36%) and D (28%) were predominated.among uropathogenic E.coli  in comparison with group A (8%) ,whereas in .commensal isolates.groups B1(36%), B2(32%) ,D (28%) were.more prevalent in compare.with group A (4%).The prevalence.of cnf1 and fimH .genes were higher in.UPEC in comparsion with.commensal isolates. However, the.prevalence of kpsMT II gene.was similar among.both groups, while hlyA gene was.higher in fecal.isolates. According to this results., microbiota may considered the main source of UPEC bacteria.                                           

scholarly journals Analysis of virulence factors and emm typing of Streptococcus pyogenes clinical isolates.

2019 ◽  
Author(s):  
Gustavo Enck Sambrano ◽  
Gustavo P Riboldi ◽  
Keli C Reiter ◽  
Thiago Galvão da Silva Paim ◽  
Neidmar Correa Tolfo ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Streptococcus Pyogenes ◽  
Virulence Genes ◽  
Clinical Isolates ◽  
Pcr Analysis ◽  
Tissue Tropism ◽  
Factors Analysis ◽  
Wide Range ◽  
Group A ◽  
Micro Organisms

Background: Streptococcus pyogenes, a Group A streptococci (GAS), is an important human pathogen that causes a wide range of infections. Methods: Twenty five clinical isolates of S. pyogenes were submitted to an emm typing and to a Real-time PCR analysis for 23 important virulence factors. Results: Fourteen emm types were found and the emm1 type was the most prevalent. The majority of the isolates were classified as emm pattern E, followed by A-C3. No pattern D was found. Among the virulence factors, the most prevalent were SpeG, Slo, C5a-peptidase and SPNA. Phage encoded virulence genes were also found among the strains, such as mf-2, SpeJ and SpeL. Discussion: The emm1 type was the most prevalent while the 13 others M types were distributed along the strains. No tissue tropism was found on the isolates. The virulence factors analysis demonstrated that chromosomally and phage-encoded genes were found, which confers a potential for high virulent micro-organisms.

scholarly journals Analysis of virulence factors and emm typing of Streptococcus pyogenes clinical isolates.

2019 ◽  
Author(s):  
Gustavo Enck Sambrano ◽  
Gustavo P Riboldi ◽  
Keli C Reiter ◽  
Thiago Galvão da Silva Paim ◽  
Neidmar Correa Tolfo ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Streptococcus Pyogenes ◽  
Virulence Genes ◽  
Clinical Isolates ◽  
Pcr Analysis ◽  
Tissue Tropism ◽  
Factors Analysis ◽  
Wide Range ◽  
Group A ◽  
Micro Organisms

Background: Streptococcus pyogenes, a Group A streptococci (GAS), is an important human pathogen that causes a wide range of infections. Methods: Twenty five clinical isolates of S. pyogenes were submitted to an emm typing and to a Real-time PCR analysis for 23 important virulence factors. Results: Fourteen emm types were found and the emm1 type was the most prevalent. The majority of the isolates were classified as emm pattern E, followed by A-C3. No pattern D was found. Among the virulence factors, the most prevalent were SpeG, Slo, C5a-peptidase and SPNA. Phage encoded virulence genes were also found among the strains, such as mf-2, SpeJ and SpeL. Discussion: The emm1 type was the most prevalent while the 13 others M types were distributed along the strains. No tissue tropism was found on the isolates. The virulence factors analysis demonstrated that chromosomally and phage-encoded genes were found, which confers a potential for high virulent micro-organisms.

scholarly journals Detection of virulence genes, phylogenetic group and antibiotic resistance of uropathogenic Escherichia coli in Mongolia

2017 ◽  
Vol 11 (01) ◽  
pp. 51-57 ◽  
Author(s):  
Yandag Munkhdelger ◽  
Nyamaa Gunregjav ◽  
Altantsetseg Dorjpurev ◽  
Nishi Juniichiro ◽  
Jav Sarantuya
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Virulence Genes ◽  
Wide Spectrum ◽  
Iron Acquisition ◽  
Uropathogenic Escherichia Coli ◽  
Phylogenetic Group ◽  
Diffusion Method ◽  
Phylogenetic Groups ◽  
E Coli

Introduction: The severity of urinary tract infection (UTI) produced by uropathogenic Escherichia coli (UPEC) is due to the expression of a wide spectrum of virulence genes. E. coli strains were divided into four phylogenetic groups (A, B1, B2 and D) based on their virulence genes. The present study aimed to assess the relationship between virulence genes, phylogenetic groups, and antibiotic resistance of UPEC. Methodology: A total of 148 E. coli were tested for antimicrobial resistance against 10 drugs using the disk diffusion method. The isolates were screened by polymerase chain reaction (PCR) for detection of virulence genes and categorized into the four major phylogenetic groups. Results: Phylogenetic group B2 was predominant (33.8%), followed by D (28.4%), A (19.6), and B1 (18.2%). A higher prevalence of fimH (89.9%), fyuA (70.3%), traT (66.2%), iutA (62.2%), kpsMTII (58.8%), and aer (56.1%) genes were found in UPEC, indicating a putative role of adhesins, iron acquisition systems, and protectins that are main cause of UTIs. The most common antibiotic resistance was to cephalotin (85.1%), ampicillin (78.4%) and the least to nitrofurantoin (5.4%) and imipenem (2%). In total, 93.9% of isolates were multidrug resistant (MDR). Conclusions: This study showed that group B2 and D were the predominant phylogenetic groups and virulence-associated genes were mostly distributed in these groups. The virulence genes encoding components of adhesins, iron acquisition systems, and protectins were highly prevalent among antibiotic-resistant UPEC. Although the majority of strains are MDR, nitrofurantoin is the drug of choice for treatment of UTI patients in Ulaanbaatar.

scholarly journals Phylogenetic Groups and Antimicrobial Susceptibility Patterns of Escherichia coli from Healthy Chicken in Eastern and Central Uganda

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Winston Kabiswa ◽  
Ann Nanteza ◽  
Gabriel Tumwine ◽  
Samuel Majalija
Keyword(s):  
Antimicrobial Resistance ◽  
Phylogenetic Group ◽  
Diffusion Method ◽  
Eastern Region ◽  
Phylogenetic Groups ◽  
Antimicrobial Drugs ◽  
E Coli ◽  
Group A ◽  
Eastern Uganda ◽  
Susceptibility Patterns

Antimicrobial resistance is an emerging problem in both humans and animals due to misuse and excessive use of drugs. Resistance in commensal E. coli isolates can be used to predict emergence of resistance in other gut microflora. The aim of this study is to determine the phylogenetic groups and antimicrobial resistance patterns of E. coli from healthy chickens in Uganda. The phylogenetic grouping of 120 fecal E. coli isolates from eastern and central Uganda was derived using the triplex PCR assay and their susceptibility patterns determined by agar disc diffusion method to 5 antimicrobial drugs. Most E. coli is segregated into phylogenetic group A comprising 84%, while 12% and 4% were in groups D and B1, respectively. Similarly most E. coli from central (87%) and eastern Uganda (82%) belonged to group A. Overall, 85 (70%) of E. coli were resistant to antimicrobial drugs, of which 72/101 (70%) are in PG A, 10 of 14 (71.4%) in PG D, and 3 of 5 (60%) in PG B1. Significantly, most of the isolates in PG A from both central (66.7%) and (60.6%) eastern Uganda were resistant to one antimicrobial. Resistance to tetracycline alone or in combination with other drugs for central and eastern Uganda in PG A is 51% and 55%, respectively. Multidrug resistance to tetracycline and ciprofloxacin or nalidixic acid was 10% and 18% in isolates from central and 10% and 12% in isolates from eastern region, respectively. Phylogenetic group A accounts for most of the E. coli in chicken from Uganda. No difference in the resistance rates between the phylogenetic groups of E. coli has been observed. The high prevalence of resistant E. coli strains from different phylogenetic groups in healthy chickens suggests antimicrobial drug selection pressure due to excessive drug in the rearing layer chickens.

scholarly journals Prevalence and characterization of Escherichia coli in the Kelantan River and its adjacent coastal waters

2020 ◽  
Vol 20 (3) ◽  
pp. 930-942
Author(s):  
Chui Wei Bong ◽  
Siong Kiat Chai ◽  
Lay Ching Chai ◽  
Ai Jun Wang ◽  
Choon Weng Lee
Keyword(s):  
Escherichia Coli ◽  
Coastal Waters ◽  
Membrane Filtration ◽  
Sea Water ◽  
Phylogenetic Group ◽  
Animal Origin ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Colony Forming Units ◽  
Phylogenetic Grouping

Abstract The presence of Escherichia coli in river and sea water may cause different levels of infections and constitutes a risk to public health. In this study, water samples were collected from 15 sites along the Kelantan River, estuaries and its adjacent coastal waters to investigate the prevalence and diversity of E. coli. A membrane filtration technique was used to enumerate E. coli and phylogenetic grouping was performed using triplex polymerase chain reaction. E. coli abundance ranged from 3.1 × 10 to 1.6 × 105 colony forming units 100 mL−1, and total suspended solids correlated significantly with E. coli abundance (r2 = 0.165, p < 0.001) and rainfall (r2 = 0.342, p < 0.001). Phylogenetic group B1 and A (59.4%) were the most prevalent, whereas groups B2 and D were least abundant. The higher abundance of phylogenetic group D at upstream sites of the Kelantan River suggested fecal contamination mainly of animal origin. Canonical-correlation analysis showed phylogenetic group B2, and phylogenetic groups A and D were greater in waters with higher inorganic nutrients (e.g. NH4, NO2 and NO3), whereas phylogenetic group B1 appeared to have better salinity tolerance between phylogenetic groups.

scholarly journals Phylogenetic Analysis and Prevalence of Urosepsis Strains of Escherichia coli Bearing Pathogenicity Island-Like Domains

2002 ◽  
Vol 70 (6) ◽  
pp. 3216-3226 ◽  
Author(s):  
Martine Bingen-Bidois ◽  
Olivier Clermont ◽  
Stéphane Bonacorsi ◽  
Mustapha Terki ◽  
Naïma Brahimi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Phylogenetic Analysis ◽  
Genetic Linkage ◽  
Virulence Genes ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Genetic Elements ◽  
Physical Linkage ◽  
Phylogenetic Grouping ◽  
Compromised Patients

ABSTRACT We characterized 100 Escherichia coli urosepsis isolates from adult patients according to host compromise status by means of ribotyping, PCR phylogenetic grouping, and PCR detection of papG alleles and the virulence-related genes sfa/foc, fyuA, irp-2, aer, hly, cnf-1 and hra. We also tested these strains for copies of pap and hly and their direct physical linkage with other virulence genes in an attempt to look for pathogenicity islands (PAIs) described for the archetypal uropathogenic strains J96, CFT073, and 536. Most of the isolates belonged to E. coli phylogenetic groups B2 and D and bore papG allele II, aer, and fyuA/irp-2. papG allele II-bearing strains were more common in noncompromised patients, while papG allele-negative strains were significantly more frequent in compromised patients. Fifteen ribotypes were identified. The three archetypal strains harbored different ribotypes, and only one-third of our urosepsis strains were genetically related to one of the archetypal strains. Three and 18 strains harbored three and two copies of pap, respectively, and 5 strains harbored two copies of hly. papGIII was physically linked to hly, cnf-1, and hra (reported to be PAI IIJ96-like genetic elements) in 14% of the strains. The PAI IIJ96-like domain was inserted within pheR tRNA in 11 strains and near leuX tRNA in 3 strains. Moreover, the colocalized genes cnf-1, hra, and hly were physically linked to papGII in four strains and to no pap gene in three strains. papGII and hly (reported to be PAI ICFT073-like genetic elements) were physically linked in 16 strains, pointing to a PAI ICFT073-like domain. Three strains contained both a PAI IIJ96-like domain and a PAI ICFTO73-like domain. Forty-two strains harbored papGII but not hly, in keeping with the presence of a PAI IICFT073-like domain. Only one strain harbored a PAI I536-like domain (hly only), and none harbored a PAI IJ96-like domain (papGI plus hly) or a PAI II536-like domain (papGIII plus hly). This study provides new data on the prevalence and variability of physical genetic linkage between pap and certain virulence-associated genes that are consistent with their colocalization on archetypal PAIs.

scholarly journals Virulence genes and phylogenetic groups of uropathogenic Escherichia coli isolates from patients with urinary tract infection and uninfected control subjects: a case-control study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Seyedeh Elham Rezatofighi ◽  
Mahsa Mirzarazi ◽  
Mansour Salehi
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract Infection ◽  
Urinary Tract ◽  
Tract Infection ◽  
Virulence Factors ◽  
Virulence Genes ◽  
Strong Association ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Healthy Humans

Abstract Background Urinary Tract Infection (UTI) is one of the most common bacterial infectious diseases which causes considerable morbidity and costly health problems. Uropathogenic Escherichia coli (UPEC), the most common pathogen causing UTI, is a highly heterogeneous group of extraintestinal pathogenic E. coli (ExPEC) which may carry a variety of virulence factors and belonging to different phylogenetic backgrounds. The current study aimed to investigate the frequency and association between various virulence factors (VFs) and phylogenetic groups of UPEC and commensal isolates. Methods UPEC and commensal E. coli strains isolated from UTI and feces of healthy humans were compared for the presence of VFs and phylogenetic groups. Association between virulence genes was investigated and cluster analysis was employed. Results According to the results, among a 30 virulence markers tested, the pathogenicity-associated island (PAI), papAH, papEF, fimH, fyuA, and traT genes prevalence were statistically significant in UPEC isolates. A strong association was found between the B2 and D phylogenetic groups and clinical isolates of UPEC; while, commensal isolates were mostly associated with phylogenetic group A. The aggregated VFs scores were more than twice higher in the UPEC isolates in comparison with the commensal isolates. Interestingly, the B2 group in both UPEC and commensal isolates had the highest VF scores. A strong positive association was found between several virulence genes. The clustering results demonstrated that UPEC or commensal E. coli isolates were highly heterogeneous due to different composition of their virulence gene pool and pathogenicity islands. Conclusion Genetic structure and VFs of UPEC strains vary from region to region; therefore, to control the UTI, the epidemiological aspects and characterization of the UPEC isolates need to be investigated in different regions. Since UPEC isolates are generally originate from the commensal strains, it may be feasible to reduce the UTI burden by interfering the intestinal colonization, particularly in the highly pathogenic clonal lineages such as B2.

PHYLOGENETIC GROUPS AND VIRULENCE GENES OF ESCHERICHIA COLI STRAINS ISOLATED FROM THE CHILDREN GUT MICROBIOTA

2020 ◽  
Vol 65 (4) ◽  
pp. 251-257
Author(s):  
Ludmila V. Suzhaeva ◽  
Maria A. Makarova ◽  
Lidiya A. Kaftyreva
Keyword(s):  
Escherichia Coli ◽  
Gut Microbiota ◽  
Virulence Genes ◽  
Intraspecific Diversity ◽  
Phylogenetic Groups ◽  
Phylogenetic Structure ◽  
Intestinal Diseases ◽  
E Coli ◽  
Geographical Regions ◽  
Tract Infections

Escherichia coli is characterized by a wide intraspecific diversity. The species includes both commensals and pathogens that cause diarrhea and extra-intestinal diseases. Pathogenic strains differ from non-pathogenic ones by the presence of virulence factors and their genes. The phylogenetic structure of the species is represented by four main groups (A, B1, B2, D), which differ in their prevalence among residents of different geographical regions. Pathogenic members of the species have been studied in detail, while non-pathogenic strains have not received such attention. This report presents the results of a study of 511 E. coli strains isolated from the gut microbiota of children without diarrhea and urinary tract infections, aged from 1 month to 17 years, living in St. Petersburg. The main phylogenetic groups were determined by PCR, and E. coli virulence genes associated with diarrhea and extra-intestinal diseases were identified. Results: population structure of E. coli is represented by the following groups: A-33.3%, B1-6.7%, B2-34.0%, D-26%. In the studied population 2.5% of strains belonded to EPEC and 4.5% to EAggEC. EPEC virulence genes were more often detected in strains of phylogroup B1, and EAggEC virulence genes in isolates of phylogroup D. The prevalence of extra - intestinal virulence genes was as follows: pap - 29.5%; sfa - 19.8%; afa - 3.3%; hly - 20.9%; cnf - 17.4%; aer-20.0%. The pap, sfa, hly, and cnf genes were detected mostly in the B2 phylogenetic group. Obtained data shows the similarity of E. coli phylogenetic groups structure in St. Petersburg with E. coli populations isolated from residents of Paris and Sydney. Analysis of the virulence genes prevalence showed the dependence of their presence on the genetic background bacteria.

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