Occurrence of virulence-related sequences and phylogenetic analysis of commensal and pathogenic avian Escherichia coli strains (APEC)

The presence of iron uptake (irp-2, fyuA, sitA, fepC, iucA), adhesion (iha, lpfA O157/O141, lpfA O157/O154, efa, toxB) and invasion (inv, ial-related DNA sequences and assignment to the four main Escherichia coli phylogenetic groups (A, B1, B2 e D) were determined in 30 commensal E. coli strains isolated from healthy chickens and in 49 APEC strains isolated from chickens presenting clinical signs of septicemia (n=24) swollen head syndrome (n=14) and omphalitis (n=11) by PCR. None of the strains presented DNA sequences related to the inv, ial, efa, and toxB genes. DNA sequences related to lpfA O157/O154, iucA, fepC, and irp-2 genes were significantly found among pathogenic strains, where iucA gene was associated with septicemia and swollen head syndrome and fepC and irp-2 genes were associated with swollen head syndrome strains. Phylogenetic typing showed that commensal and omphalitis strains belonged mainly to phylogenetic Group A and swollen head syndrome to phylogenetic Group D. Septicemic strains were assigned in phylogenetic Groups A and D. These data could suggest that clonal lineage of septicemic APEC strains have a multiple ancestor origin; one from a pathogenic bacteria ancestor and other from a non-pathogenic ancestor that evolved by the acquisition of virulence related sequences through horizontal gene transfer. Swollen head syndrome may constitute a pathogenic clonal group. By the other side, omphalitis strains probably constitute a non-pathogenic clonal group, and could cause omphalitis as an opportunistic infection. The sharing of virulence related sequences by human pathogenic E. coli and APEC strains could indicate that APEC strains could be a source of virulence genes to human strains and could represent a zoonotic risk.

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CTX-M-Producing Escherichia coli in Lithuania: Associations Between Sites of Infection, Coresistance, and Phylogenetic Groups

Medicina ◽

10.3390/medicina49090061 ◽

2013 ◽

Vol 49 (9) ◽

pp. 61 ◽

Cited By ~ 2

Author(s):

Agnė Giedraitienė ◽

Astra Vitkauskienė ◽

Virginija Ašmonienė ◽

Rita Plančiūnienė ◽

Sandrita Šimonytė ◽

...

Keyword(s):

Escherichia Coli ◽

Lower Respiratory Tract ◽

Phylogenetic Group ◽

Third Generation ◽

Phylogenetic Groups ◽

E Coli ◽

The Third ◽

Group A ◽

Third Generation Cephalosporins ◽

M 14

Increasing resistance of Escherichia coli (E. coli) to antibiotics, especially to the third-generation cephalosporins, has prompted studies on widespread resistance genes such as blaCTX-M and differentiation of E. coli to phylogenetic groups. The aim of this study was to determine the associations between the CTX-M type and the phylogenetic group, the site of infection, and coresistance in Lithuanian E. coli isolates producing β-lactamases. Material and Methods. A total of 90 E. coli ESBL strains were recovered from the lower respiratory tract, the urinary tract, sterile body sites, wounds, and other body sites between 2008 and 2012. The E. coli isolates resistant to at least 2 antibiotics with different modes of action along with resistance to cefotaxime were considered as multiresistant. The blaCTX-M, blaTEM, blaOXA-1, and blaSHV genes, the phylogenetic groups, and the resistance profiles were analyzed. Results. Of the 90 isolates, 84 (93.3%) were classified as multiresistant and 6 (6.6%) as resistant. The blaCTX-M-15 gene was the most prevalent gene followed by the blaCTX-M-14 and blaCTX-M-92 genes. The logistic regression analysis revealed the associations between CTX-M-15 and resistance to ceftriaxone, between CTX-M-14 and resistance to cefoxitin, aztreonam, ampicillin/sulbactam, ticarcillin/clavulanic acid, and tobramycin, and between CTX-M-92 and resistance to cefepime, piperacillin/tazobactam, gentamicin, and tobramycin. Conclusions. The results of this study showed a significant association between CTX-M-15, CTX-M-14, and CTX-M-92 β-lactamases and resistance to some antibiotics as well as CTX‑M-14 β-lactamase and phylogenetic group A in the Lithuanian population. The associations between the CTX-M type and the site of infection were not determined.

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Recent Emergence of Clonal Group O25b:K1:H4-B2-ST131 ibeA Strains among Escherichia coli Poultry Isolates, Including CTX-M-9-Producing Strains, and Comparison with Clinical Human Isolates

Applied and Environmental Microbiology ◽

10.1128/aem.01112-10 ◽

2010 ◽

Vol 76 (21) ◽

pp. 6991-6997 ◽

Cited By ~ 66

Author(s):

Azucena Mora ◽

Alexandra Herrera ◽

Rosalia Mamani ◽

Cecilia López ◽

María Pilar Alonso ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Gene ◽

Clonal Group ◽

E Coli ◽

Strain Collection ◽

Zoonotic Risk ◽

Recent Emergence ◽

Avian Origin ◽

K1 Capsule ◽

M 14

ABSTRACT To discern the possible spread of the Escherichia coli O25b:H4-ST131 clonal group in poultry and the zoonotic potential of avian strains, we made a retrospective search of our strain collection and compared the findings for those strains with the findings for current strains. Thus, we have characterized a collection of 19 avian O25b:H4-ST131 E. coli strains isolated from 1995 to 2010 which, interestingly, harbored the ibeA gene. Using this virulence gene as a criterion for selection, we compared those 19 avian strains with 33 human O25b:H4-ST131 ibeA-positive E. coli strains obtained from patients with extraintestinal infections (1993 to 2009). All 52 O25b:H4-ST131 ibeA-positive E. coli strains shared the fimH, kpsMII, malX, and usp genes but showed statistically significant differences in nine virulence factors, namely, papGIII, cdtB, sat, and kpsMII K5, which were associated with human strains, and iroN, kpsMII K1, cvaC, iss, and tsh, which were associated with strains of avian origin. The XbaI macrorestriction profiles of the 52 E. coli O25b:H4-ST131 ibeA-positive strains revealed 11 clusters (clusters I to XI) of >85% similarity, with four clusters including strains of human and avian origin. Cluster VII (90.9% similarity) grouped 10 strains (7 avian and 3 human strains) that mostly produced CTX-M-9 and that also shared the same virulence profile. Finally, we compared the macrorestriction profiles of the 12 CTX-M-9-producing O25b:H4-ST131 ibeA strains (7 avian and 5 human strains) identified among the 52 strains with those of 15 human O25b:H4-ST131 CTX-M-14-, CTX-M-15-, and CTX-M-32-producing strains that proved to be negative for ibeA and showed that they clearly differed in the level of similarity from the CTX-M-9-producing strains. In conclusion, E. coli clonal group O25b:H4-ST131 ibeA has recently emerged among avian isolates with the new acquisition of the K1 capsule antigen and includes CTX-M-9-producing strains. This clonal group represents a real zoonotic risk that has crossed the barrier between human and avian hosts.

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Prominence of an O75 Clonal Group (Clonal Complex 14) among Non-ST131 Fluoroquinolone-Resistant Escherichia coli Causing Extraintestinal Infections in Humans and Dogs in Australia

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.06120-11 ◽

2012 ◽

Vol 56 (7) ◽

pp. 3898-3904 ◽

Cited By ~ 32

Author(s):

Joanne L. Platell ◽

Darren J. Trott ◽

James R. Johnson ◽

Peter Heisig ◽

Anke Heisig ◽

...

Keyword(s):

Escherichia Coli ◽

Clonal Complex ◽

Resistance Mechanism ◽

Multidrug Resistant ◽

Phylogenetic Group ◽

Mechanism Analysis ◽

Content Type ◽

Clonal Group ◽

E Coli ◽

Animal Medicine

ABSTRACTFluoroquinolone (FQ)-resistant extraintestinal pathogenicEscherichia coli(FQrExPEC) strains from phylogenetic group B2 are undergoing epidemic spread. Isolates belonging to phylogenetic group B2 are generally more virulent than otherE. coliisolates; therefore, resistance to FQs among group B2 isolates is concerning. Although clonal expansion of sequence type 131 (ST131) is a major factor, the contribution of additional clonal groups has not been quantified. Group B2 FQrExPEC isolates from humans (n= 250) and dogs (n= 12) in Australia were screened for ST131, a recently recognized and rapidly emerging multidrug-resistant and virulent clonal group that is important in both human and companion animal medicine. Non-ST131 isolates underwent virulence genotyping, PCR-based O typing, partial multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), and FQ resistance mechanism analysis. Of 49 non-ST131 isolates (45 human, 4 canine), 49% (24 human, 2 canine) represented O-type O75 and exhibited conserved virulence genotypes (F10papAallele,iha,fimH,sat,vat,fyuA,iutA,kpsMII,usp,ompT,malX, K1/K5 capsule) and MLST allele profiles corresponding with clonal complex CC14. Two clusters, each containing canine and human isolates, were identified by PFGE (differentiated by K1 and K5 capsules). Australian FQrO75 isolates exhibited commonality with an historical FQ-susceptible O75 urosepsis isolate (also CC14). The isolation from humans and dogs of highly similar FQrderivatives of the classic O75:K1/K5 (CC14) ExPEC lineage suggests recent acquisition of FQ resistance and potential cross-host-species transfer. This lineage should be targeted with ST131 in future epidemiological investigations of FQrExPEC.

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

The Scientific World JOURNAL ◽

10.1155/2015/610403 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 10

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.

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Phylogenetic groups and antimicrobial susceptibility patterns of uropathogenic Escherichia coli clinical isolates from patients at Mulago National Referral Hospital, Kampala, Uganda

F1000Research ◽

10.12688/f1000research.20930.1 ◽

2019 ◽

Vol 8 ◽

pp. 1828 ◽

Cited By ~ 1

Author(s):

Paul Katongole ◽

Daniel Bulwadda Kisawuzi ◽

Henry Kyobe Bbosa ◽

David Patrick Kateete ◽

Christine Florence Najjuka

Keyword(s):

Escherichia Coli ◽

Antimicrobial Susceptibility ◽

Phylogenetic Group ◽

Diffusion Method ◽

Clinical Microbiology Laboratory ◽

Phylogenetic Groups ◽

E Coli ◽

Pcr Method ◽

Tract Infections ◽

Susceptibility Patterns

Introduction: Uropathogenic Escherichia coli (UPEC) remains the most common cause of urinary tract infections (UTIs). They account for over 80-90% of all community-acquired and 30-50% of all hospital-acquired UTIs. E. coli strains have been found to belong to evolutionary origins known as phylogenetic groups. In 2013, Clermont classified E. coli strains into eight phylogenetic groups using the quadruplex PCR method. The aim of this study was to identify the phylogenetic groups of UPEC strains in Uganda using Clermont’s quadruplex PCR method and to assess their antibiotic susceptibility patterns in Uganda. Methods: In this cross-sectional study, 140 stored uropathogenic E. coli isolates from the Clinical Microbiology Laboratory, Department of Medical Microbiology, College of Health Sciences Makerere University were subjected to phylogenetic typing by a quadruplex PCR method. Antimicrobial susceptibility testing was performed by disk diffusion method according to Clinical & Laboratory Standards Institute (CLSI) guidelines. Phenotypic detection of extended-spectrum beta-lactamase, AmpC and carbapenemases was done according to CLSI guidelines and Laboratory SOPs. Results: Phylogenetic group B2 (40%) was the most predominant, followed by A (6.23%), clade I and II (5%), D and E (each 2.14%), B1 (1.43%) and F and C (each 0.71%). The most common resistant antibiotic was trimethoprim-sulphamethoxazole (90.71%) and the least was imipenem (1.43%). In total, 73.57% of isolates were multi-drug resistant (MDR). Antibiotic resistance was mainly detected in phylogenetic group B2 (54%). Conclusions: Our findings showed the high prevalence of MDR E. coli isolates, with the dominance of phylogenetic group B2. About 9% of E. coli isolates belonged to the newly described phylogroups C, E, F, and clade I and II.

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

The Journal of Infection in Developing Countries ◽

10.3855/jidc.7903 ◽

2017 ◽

Vol 11 (01) ◽

pp. 51-57 ◽

Cited By ~ 17

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.

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Characterization of commensal Escherichia coli isolates from slaughtered sheep in Mexico

The Journal of Infection in Developing Countries ◽

10.3855/jidc.14001 ◽

2021 ◽

Vol 15 (11) ◽

pp. 1755-1760

Author(s):

Jorge Acosta-Dibarrat ◽

Edgar Enriquez-Gómez ◽

Martín Talavera-Rojas ◽

Edgardo Soriano-Vargas ◽

Armando Navarro ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Resistance ◽

Multidrug Resistant ◽

Phylogenetic Group ◽

Phylogenetic Groups ◽

E Coli ◽

New Information ◽

Antimicrobial Resistance Genes ◽

Uremic Syndrome

Introduction: Commensal Escherichia coli is defined as bacteria without known virulence factors that could be playing a specific role in some diseases; however, they could be responsible to disseminate antimicrobial resistance genes to other microorganisms. This study aimed to characterize the commensal E. coli isolates obtained from slaughtered sheep in the central region of Mexico. Methodology: Isolates were classified as commensal E. coli when distinctive genes related to diarrheagenic pathotypes (stx1, stx2, eae, bfp, LT, stp, ipaH, and aggR) were discarded by PCR. Identification of serotype, phylogenetic group, and antimicrobial resistance was also performed. Results: A total of 41 isolates were characterized. The phylogenetic groups found were B1 in 37 isolates (90.2%), A in 2 (4.8%), and 1 isolate (2.4%) for C and D groups. Serotypes associated with diarrhea in humans (O104:H2 and O154:NM) and hemolytic uremic syndrome (O8:NM) were detected. Thirty-three isolates (80%) were resistant to ceftazidime, 23 (56%), to tetracycline 8 (19.5%) to ampicillin, and 1 to amikacin. Six isolates (14.6%) were multidrug-resistant. Conclusions: This study provides new information about commensal E. coli in slaughtered sheep, high percentages of resistance to antibiotics, and different profiles of antimicrobial resistance were found, their dissemination constitute a risk factor towards the consuming population.

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

Journal of Veterinary Medicine ◽

10.1155/2018/9126467 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6 ◽

Cited By ~ 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.

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Iha from an Escherichia coli Urinary Tract Infection Outbreak Clonal Group A Strain Is Expressed In Vivo in the Mouse Urinary Tract and Functions as a Catecholate Siderophore Receptor

Infection and Immunity ◽

10.1128/iai.00107-06 ◽

2006 ◽

Vol 74 (6) ◽

pp. 3427-3436 ◽

Cited By ~ 41

Author(s):

Simon Léveillé ◽

Mélissa Caza ◽

James R. Johnson ◽

Connie Clabots ◽

Mourad Sabri ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract Infection ◽

Urinary Tract ◽

Tract Infection ◽

Growth Promotion ◽

Clonal Group ◽

E Coli ◽

Group A ◽

K 12

ABSTRACT Virulence factors of pathogenic Escherichia coli belonging to a recently emerged and disseminated clonal group associated with urinary tract infection (UTI), provisionally designated clonal group A (CGA), have not been experimentally investigated. We used a mouse model of ascending UTI with CGA member strain UCB34 in order to identify genes of CGA that contribute to UTI. iha was identified to be expressed by strain UCB34 in the mouse kidney using selective capture of transcribed sequences. iha from strain UCB34 demonstrated a siderophore receptor phenotype when cloned in a catecholate siderophore receptor-negative E. coli K-12 strain, as shown by growth promotion experiments and uptake of 55Fe complexed to enterobactin or its linear 2, 3-dihydroxybenzoylserine (DHBS) siderophore derivatives. Siderophore-mediated growth promotion by Iha was TonB dependent. Growth and iron uptake were more marked with linear DHBS derivatives than with purified enterobactin. The reported phenotype of adherence to epithelial cells conferred by expressing iha from a multicopy cloning vector in a poorly adherent E. coli K-12 host strain was confirmed to be specific to iha, in comparison with other siderophore receptor genes. iha expression was regulated by the ferric uptake regulator Fur and by iron availability, as shown by real-time reverse transcriptase PCR. In a competitive infection experiment using the mouse UTI model, wild-type strain UCB34 significantly outcompeted an isogenic iha null mutant. Iha thus represents a Fur-regulated catecholate siderophore receptor that, uniquely, exhibits an adherence-enhancing phenotype and is the first described urovirulence factor identified in a CGA strain.

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

Water Science & Technology Water Supply ◽

10.2166/ws.2020.018 ◽

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.

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