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Antimicrobial resistance and conjugative R plasmids in Escherichia coli strains isolated from animals in Peninsular Malaysia

Koh CL, Kok CH

Southeast Asian J Trop Med Public Health, 1984 Mar;15(1):37-43.
PMID: 6377513

Fifteen independent E. coli strains of avian, bovine and porcine origin in Peninsular Malaysia were tested for antibiotic resistance and conjugative R plasmids. Eight (53%) isolates were found to be antibiotic resistant. Among them, 37.5% were mono-resistant and 62.5% were resistant to three or more antibiotics, i.e., multi-resistant. All of them were resistant to Tc and sensitive to Gm and Nx. Three of the eight antibiotic resistant strains were able to transfer all or part of their resistance to an E. coli K12 recipient by conjugation. The transfer frequencies of Km, Sm and Tc resistance of the three donors varied between 4.5 X 10(-8) to 6.8 X 10(-7). Analysis of the plasmid profiles of all the three donors and their respective transconjugants after agarose gel electrophoresis provided conclusive evidence that the transferable resistance traits were plasmid-mediated.

Matched MeSH terms: Escherichia coli Infections/drug therapy
Fulltext Efficacy of a bacteriophage isolated from chickens as a therapeutic agent for colibacillosis in broiler chickens

Lau GL, Sieo CC, Tan WS, Hair-Bejo M, Jalila A, Ho YW

Poult Sci, 2010 Dec;89(12):2589-96.
PMID: 21076096 DOI: 10.3382/ps.2010-00904

The efficacy of bacteriophage EC1, a lytic bacteriophage, against Escherichia coli O78:K80, which causes colibacillosis in poultry, was determined in the present study. A total of 480 one-day-old birds were randomly assigned to 4 treatments groups, each with 4 pens of 30 birds. Birds from the control groups (groups I and II) received PBS (pH 7.4) or 10(10) pfu of bacteriophage EC1, respectively. Group III consisted of birds challenged with 10(8) cfu of E. coli O78:K80 and treated with 10(10) pfu of bacteriophage EC1 at 2 h postinfection, whereas birds from group IV were challenged with 10(8) cfu of E. coli O78:K80 only. All the materials were introduced into the birds by intratracheal inoculation. Based on the results of the present study, the infection was found to be less severe in the treated E. coli-challenged group. Mean total viable cell counts of E. coli identified on eosin methylene blue agar (designated EMB + E. coli) in the lungs were significantly lower in treated, E. coli-challenged birds than in untreated, E. coli-challenged birds on d 1 and 2 postinfection. The EMB + E. coli isolation frequency was also lower in treated birds; no E. coli was detectable in blood samples on any sampling day, and E. coli were isolated only in the liver, heart, and spleen of treated chickens at a ratio of 2/6, 1/6, and 3/6, respectively, at d 1 postinfection. The BW of birds from the E. coli-challenged group treated with bacteriophage EC1 were not significantly different from those of birds from both control groups but were 15.4% higher than those of the untreated, E. coli-challenged group on d 21 postinfection. The total mortality rate of birds during the 3-wk experimental period decreased from 83.3% in the untreated, E. coli-challenged birds (group IV) to 13.3% in birds treated with bacteriophage EC1 (group III). These results suggest that bacteriophage EC1 is effective in vivo and could be used to treat colibacillosis in chickens.

Matched MeSH terms: Escherichia coli Infections/pathology; Escherichia coli Infections/therapy; Escherichia coli Infections/transmission; Escherichia coli Infections/veterinary*
Mucosal and systemic responses of immunogenic vaccines candidates against enteric Escherichia coli infections in ruminants: A review

Lawan A, Jesse FFA, Idris UH, Odhah MN, Arsalan M, Muhammad NA, et al.

Microb Pathog, 2018 Apr;117:175-183.
PMID: 29471137 DOI: 10.1016/j.micpath.2018.02.039

Innumerable Escherichia coli of animal origin are identified, which are of economic significance, likewise, cattle, sheep and goats are the carrier of enterohaemorrhagic E. coli, which are less pathogenic, and can spread to people by way of direct contact and through the contamination of foodstuff or portable drinking water, causing serious illness. The immunization of ruminants has been carried out for ages and is largely acknowledged as the most economical and maintainable process of monitoring E. coli infection in ruminants. Yet, only a limited number of E. coli vaccines are obtainable. Mucosal surfaces are the most important ingress for E. coli and thus mucosal immune responses function as the primary means of fortification. Largely contemporary vaccination processes are done by parenteral administration and merely limited number of E. coli vaccines are inoculated via mucosal itinerary, due to its decreased efficacy. Nevertheless, aiming at maximal mucosal partitions to stimulate defensive immunity at both mucosal compartments and systemic site epitomises a prodigious task. Enormous determinations are involved in order to improve on novel mucosal E. coli vaccines candidate by choosing apposite antigens with potent immunogenicity, manipulating novel mucosal itineraries of inoculation and choosing immune-inducing adjuvants. The target of E. coli mucosal vaccines is to stimulate a comprehensive, effective and defensive immunity by specifically counteracting the antibodies at mucosal linings and by the stimulation of cellular immunity. Furthermore, effective E. coli mucosal vaccine would make vaccination measures stress-free and appropriate for large number of inoculation. On account of contemporary advancement in proteomics, metagenomics, metabolomics and transcriptomics research, a comprehensive appraisal of the immeasurable genes and proteins that were divulged by a bacterium is now in easy reach. Moreover, there exist marvellous prospects in this bourgeoning technologies in comprehending the host bacteria affiliation. Accordingly, the flourishing knowledge could massively guarantee to the progression of immunogenic vaccines against E. coli infections in both humans and animals. This review highlight and expounds on the current prominence of mucosal and systemic immunogenic vaccines for the prevention of E. coli infections in ruminants.

Matched MeSH terms: Escherichia coli Infections/immunology*; Escherichia coli Infections/microbiology; Escherichia coli Infections/prevention & control*; Escherichia coli Infections/veterinary*
Fulltext Lineage-Specific Methyltransferases Define the Methylome of the Globally Disseminated Escherichia coli ST131 Clone

Forde BM, Phan MD, Gawthorne JA, Ashcroft MM, Stanton-Cook M, Sarkar S, et al.

mBio, 2015 Nov 17;6(6):e01602-15.
PMID: 26578678 DOI: 10.1128/mBio.01602-15

Escherichia coli sequence type 131 (ST131) is a clone of uropathogenic E. coli that has emerged rapidly and disseminated globally in both clinical and community settings. Members of the ST131 lineage from across the globe have been comprehensively characterized in terms of antibiotic resistance, virulence potential, and pathogenicity, but to date nothing is known about the methylome of these important human pathogens. Here we used single-molecule real-time (SMRT) PacBio sequencing to determine the methylome of E. coli EC958, the most-well-characterized completely sequenced ST131 strain. Our analysis of 52,081 methylated adenines in the genome of EC958 discovered three (m6)A methylation motifs that have not been described previously. Subsequent SMRT sequencing of isogenic knockout mutants identified the two type I methyltransferases (MTases) and one type IIG MTase responsible for (m6)A methylation of novel recognition sites. Although both type I sites were rare, the type IIG sites accounted for more than 12% of all methylated adenines in EC958. Analysis of the distribution of MTase genes across 95 ST131 genomes revealed their prevalence is highly conserved within the ST131 lineage, with most variation due to the presence or absence of mobile genetic elements on which individual MTase genes are located.
IMPORTANCE: DNA modification plays a crucial role in bacterial regulation. Despite several examples demonstrating the role of methyltransferase (MTase) enzymes in bacterial virulence, investigation of this phenomenon on a whole-genome scale has remained elusive until now. Here we used single-molecule real-time (SMRT) sequencing to determine the first complete methylome of a strain from the multidrug-resistant E. coli sequence type 131 (ST131) lineage. By interrogating the methylome computationally and with further SMRT sequencing of isogenic mutants representing previously uncharacterized MTase genes, we defined the target sequences of three novel ST131-specific MTases and determined the genomic distribution of all MTase target sequences. Using a large collection of 95 previously sequenced ST131 genomes, we identified mobile genetic elements as a major factor driving diversity in DNA methylation patterns. Overall, our analysis highlights the potential for DNA methylation to dramatically influence gene regulation at the transcriptional level within a well-defined E. coli clone.

Matched MeSH terms: Escherichia coli Infections/microbiology; Escherichia coli Infections/epidemiology
Carbapenem and colistin resistance in Enterobacteriaceae in Southeast Asia: Review and mapping of emerging and overlapping challenges

Malchione MD, Torres LM, Hartley DM, Koch M, Goodman JL

Int J Antimicrob Agents, 2019 Oct;54(4):381-399.
PMID: 31369812 DOI: 10.1016/j.ijantimicag.2019.07.019

Carbapenem-resistant Enterobacteriaceae infections have spread globally, leaving polymyxins, including colistin, as 'last-resort treatments'. Emerging colistin resistance raises the spectre of untreatable infections. Despite this threat, data remain limited for much of the world, including Southeast Asia where only 3 of 11 nations submitted data on carbapenem and colistin resistance for recent World Health Organization (WHO) reports. To improve our understanding of the challenge, we utilised broad strategies to search for and analyse data on carbapenem and colistin resistance among Escherichia coli and Klebsiella in Southeast Asia. We found 258 studies containing 526 unique reports and document carbapenem-resistant E. coli and Klebsiella in 8 and 9 of 11 nations, respectively. We estimated carbapenem resistance proportions through meta-analysis of extracted data for nations with ≥100 representative isolates. Estimated resistance among Klebsiella was high (>5%) in four nations (Indonesia, Philippines, Thailand and Vietnam), moderate (1-5%) in two nations (Malaysia and Singapore) and low (<1%) in two nations (Cambodia and Brunei). For E. coli, resistance was generally lower but was high in two of seven nations with ≥100 isolates (Indonesia and Myanmar). The most common carbapenemases were NDM metallo-β-lactamases and OXA β-lactamases. Despite sparse data, polymyxin resistance was documented in 8 of 11 nations, with mcr-1 being the predominant genotype. Widespread presence of carbapenem and polymyxin resistance, including their overlap in eight nations, represents a continuing risk and increases the threat of infections resistant to both classes. These findings, and remaining data gaps, highlight the urgent need for sufficiently-resourced robust antimicrobial resistance surveillance.

Matched MeSH terms: Escherichia coli Infections/microbiology; Escherichia coli Infections/epidemiology*
Fulltext Risk factors and spatial distribution of extended spectrum β-lactamase-producing- Escherichia coli at retail poultry meat markets in Malaysia: a cross-sectional study

Aliyu AB, Saleha AA, Jalila A, Zunita Z

BMC Public Health, 2016 08 02;16:699.
PMID: 27484086 DOI: 10.1186/s12889-016-3377-2

BACKGROUND: The significant role of retail poultry meat as an important exposure pathway for the acquisition and transmission of extended spectrum β-lactamase-producing Escherichia coli (ESBL-EC) into the human population warrants understanding concerning those operational practices associated with dissemination of ESBL-EC in poultry meat retailing. Hence, the objective of this study was to determine the prevalence, spatial distribution and potential risk factors associated with the dissemination of ESBL-EC in poultry meat retail at wet-markets in Selangor, Malaysia.
METHODS: Poultry meat (breast, wing, thigh, and keel) as well as the contact surfaces of weighing scales and cutting boards were sampled to detect ESBL-EC by using culture and disk combination methods and polymerase chain reaction assays. Besides, questionnaire was used to obtain data and information pertaining to those operational practices that may possibly explain the occurrence of ESBL-EC. The data were analysed using logistic regression analysis at 95 % CI.
RESULTS: The overall prevalence of ESBL-EC was 48.8 % (95 % CI, 42 - 55 %). Among the risk factors that were explored, type of countertop, sanitation of the stall environment, source of cleaning water, and type of cutting board were found to be significantly associated with the presence of ESBL-EC.
CONCLUSIONS: Thus, in order to prevent or reduce the presence of ESBL-EC and other contaminants at the retail-outlet, there is a need to design a process control system based on the current prevailing practices in order to reduce cross contamination, as well as to improve food safety and consumer health.

Matched MeSH terms: Escherichia coli Infections/etiology; Escherichia coli Infections/microbiology*
Antibiotic resistance, plasmid profile and RAPD-PCR analysis of enteropathogenic Escherichia coli (EPEC) clinical isolates

Wan KF, Radu S, Cheah YK, Benjamin PG, Ling CM, Hon SF, et al.

Southeast Asian J Trop Med Public Health, 2003 Sep;34(3):620-6.
PMID: 15115139

Enteropathogenic Escherichia coli (EPEC) is a leading cause of diarrhea among infants in developing countries. A total of 38 EPEC isolates, obtained from diarrhea patients of Hospital Miri, Sarawak, were investigated through plasmid profile, antibiotic resistance and randomly amplified polymorphic DNA (RAPD) analysis. From the 8 types of antibiotics used, all isolates were 100% resistant to furoxime, cephalothin and sulphamethoxazole and showed high multiple antibiotic resistant (MAR) indexes, ranging from 0.5 to 1.0. In plasmid profiling, 22 isolates (58%) showed the presence of one or more plasmids in the range 1.0 to 30.9 mDa. The dendrogram obtained from the results of the RAPD-PCR discriminated the isolates into 30 single isolates and 3 clusters at the level of 40% similarity. The EPEC isolates were highly diverse, as shown by their differing plasmid profiles, antibiotic resistance patterns and RAPD profiles.

Matched MeSH terms: Escherichia coli Infections/microbiology*; Escherichia coli Infections/epidemiology
Enteropathogenic Escherichia coli diarrhoea in Malaysian children

Jegathesan M, Singh RB, Kanaganayagy M, Soon LE

Southeast Asian J Trop Med Public Health, 1975 Mar;6(1):61-7.
PMID: 1096307
Matched MeSH terms: Escherichia coli Infections/microbiology*; Escherichia coli Infections/epidemiology
Fulltext Neonatal bartter syndrome

Wong AC, Chan LG

Med J Malaysia, 2014 Oct;69(5):229-30.
PMID: 25638238 MyJurnal

We report a case of neonatal Bartter syndrome in a 31 weeks premature baby girl with antenatal unexplained polyhydramnios requiring amnioreduction. She presented with early onset E. coli septicaemia and severe dehydration leading to pre-renal renal impairment which obscure the typical biochemical changes of hypokalaemic hypochloraemic metabolic alkalosis.

Matched MeSH terms: Escherichia coli Infections
Prevalence and characterization of multidrug-resistant and extended-spectrum beta-lactamase-producing Escherichia coli from pediatric wards of a Malaysian hospital

Ho WS, Balan G, Puthucheary S, Kong BH, Lim KT, Tan LK, et al.

Microb Drug Resist, 2012 Aug;18(4):408-16.
PMID: 22394084 DOI: 10.1089/mdr.2011.0222

The emergence of Escherichia coli resistant to extended-spectrum cephalosporins (ESCs) is of concern as ESC is often used to treat infections by Gram-negative bacteria. One-hundred and ten E. coli strains isolated in 2009-2010 from children warded in a Malaysian tertiary hospital were analyzed for their antibiograms, carriage of extended-spectrum beta-lactamase (ESBL) and AmpC genes, possible inclusion of the beta-lactamase genes on an integron platform, and their genetic relatedness. All E. coli strains were sensitive to carbapenems. About 46% of strains were multidrug resistant (MDR; i.e., resistant to ≥3 antibiotic classes) and almost half (45%) were nonsusceptible to ESCs. Among the MDR strains, high resistance rates were observed for ampicillin (98%), tetracycline (75%), and trimethoprim/sulfamethoxazole (73%). Out of 110 strains, bla(TEM-1) (49.1%), bla(CTX-M) (11.8%), and bla(CMY-2) (6.4%) were detected. Twenty-one strains were ESBL producers. CTX-M-15 was the predominant CTX-M variant found and this is the first report of a CTX-M-27-producing E. coli strain from Malaysia. Majority (3.1%) of the strains harbored class 1 integron-encoded integrases with a predominance of aadA and dfr genes within the integron variable region. No gene cassette encoding ESBL genes was found and integrons were not significantly associated with ESBL or non-ESBL producers. Possible clonal expansion was observed for few CTX-M-15-positive strains but the O25-ST131 E. coli clone known to harbor CTX-M-15 was not detected while CMY-2-positive strains were genetically diverse.

Matched MeSH terms: Escherichia coli Infections/drug therapy; Escherichia coli Infections/microbiology*; Escherichia coli Infections/epidemiology
Cephalhematoma infected by Escherichia coli presenting as an extensive scalp abscess

Wong CS, Cheah FC

J Pediatr Surg, 2012 Dec;47(12):2336-40.
PMID: 23217901 DOI: 10.1016/j.jpedsurg.2012.09.029

Cephalhematoma is normally a self-limiting condition affecting 1%-2% of live births, especially following instrumental forceps delivery. The sub-periosteal bleed is characteristically limited by the cranial sutures. Although benign in most instances, this condition may, in a small proportion of cases, be complicated by hyperbilirubinemia or scalp infection. We describe a case of cephalhematoma in a newborn infant infected with Escherichia coli resulting in an extensive deep seated scalp abscess. The infection was also systemic causing E. coli septicemia and initial assessment assumed local extension including bone and meningeal to cause skull osteomyelitis and meningitis respectively. Further investigations and multiple-modality imaging with ultrasound, CT scan and bone scintigraphy outlined the involvement as limited to the scalp, resulting in a shorter antibiotic treatment period and earlier discharge from hospital. The infant recovered well with parenteral antibiotics, saucerization of the abscess and a later skin grafting procedure.

Matched MeSH terms: Escherichia coli Infections/diagnosis; Escherichia coli Infections/microbiology*; Escherichia coli Infections/therapy
Fulltext Shiga toxin sub-type 2a increases the efficiency of Escherichia coli O157 transmission between animals and restricts epithelial regeneration in bovine enteroids

Fitzgerald SF, Beckett AE, Palarea-Albaladejo J, McAteer S, Shaaban S, Morgan J, et al.

PLoS Pathog, 2019 10;15(10):e1008003.
PMID: 31581229 DOI: 10.1371/journal.ppat.1008003

Specific Escherichia coli isolates lysogenised with prophages that express Shiga toxin (Stx) can be a threat to human health, with cattle being an important natural reservoir. In many countries the most severe pathology is associated with enterohaemorrhagic E. coli (EHEC) serogroups that express Stx subtype 2a. In the United Kingdom, phage type (PT) 21/28 O157 strains have emerged as the predominant cause of life-threatening EHEC infections and this phage type commonly encodes both Stx2a and Stx2c toxin types. PT21/28 is also epidemiologically linked to super-shedding (>103 cfu/g of faeces) which is significant for inter-animal transmission and human infection as demonstrated using modelling studies. We demonstrate that Stx2a is the main toxin produced by stx2a+/stx2c+ PT21/28 strains induced with mitomycin C and this is associated with more rapid induction of gene expression from the Stx2a-encoding prophage compared to that from the Stx2c-encoding prophage. Bacterial supernatants containing either Stx2a and/or Stx2c were demonstrated to restrict growth of bovine gastrointestinal organoids with no restriction when toxin production was not induced or prevented by mutation. Isogenic strains that differed in their capacity to produce Stx2a were selected for experimental oral colonisation of calves to assess the significance of Stx2a for both super-shedding and transmission between animals. Restoration of Stx2a expression in a PT21/28 background significantly increased animal-to-animal transmission and the number of sentinel animals that became super-shedders. We propose that while both Stx2a and Stx2c can restrict regeneration of the epithelium, it is the relatively rapid and higher levels of Stx2a induction, compared to Stx2c, that have contributed to the successful emergence of Stx2a+ E. coli isolates in cattle in the last 40 years. We propose a model in which Stx2a enhances E. coli O157 colonisation of in-contact animals by restricting regeneration and turnover of the colonised gastrointestinal epithelium.

Matched MeSH terms: Escherichia coli Infections/drug therapy; Escherichia coli Infections/microbiology; Escherichia coli Infections/veterinary*
Fulltext Genotypic and phenotypic profiles of Escherichia coli isolates belonging to clinical sequence type 131 (ST131), clinical non-ST131, and fecal non-ST131 lineages from India

Hussain A, Ranjan A, Nandanwar N, Babbar A, Jadhav S, Ahmed N

Antimicrob Agents Chemother, 2014 Dec;58(12):7240-9.
PMID: 25246402 DOI: 10.1128/AAC.03320-14

In view of the epidemiological success of CTX-M-15-producing lineages of Escherichia coli and particularly of sequence type 131 (ST131), it is of significant interest to explore its prevalence in countries such as India and to determine if antibiotic resistance, virulence, metabolic potential, and/or the genetic architecture of the ST131 isolates differ from those of non-ST131 isolates. A collection of 126 E. coli isolates comprising 43 ST131 E. coli, 40 non-ST131 E. coli, and 43 fecal E. coli isolates collected from a tertiary care hospital in India was analyzed. These isolates were subjected to enterobacterial repetitive intergenic consensus (ERIC)-based fingerprinting, O typing, phylogenetic grouping, antibiotic sensitivity testing, and virulence and antimicrobial resistance gene (VAG) detection. Representative isolates from this collection were also analyzed by multilocus sequence typing (MLST), conjugation, metabolic profiling, biofilm production assay, and zebra fish lethality assay. All of the 43 ST131 E. coli isolates were exclusively associated with phylogenetic group B2 (100%), while most of the clinical non-ST131 and stool non-ST131 E. coli isolates were affiliated with the B2 (38%) and A (58%) phylogenetic groups, respectively. Significantly greater proportions of ST131 isolates (58%) than non-ST131 isolates (clinical and stool E. coli isolates, 5% each) were technically identified to be extraintestinal pathogenic E. coli (ExPEC). The clinical ST131, clinical non-ST131, and stool non-ST131 E. coli isolates exhibited high rates of multidrug resistance (95%, 91%, and 91%, respectively), extended-spectrum-β-lactamase (ESBL) production (86%, 83%, and 91%, respectively), and metallo-β-lactamase (MBL) production (28%, 33%, and 0%, respectively). CTX-M-15 was strongly linked with ESBL production in ST131 isolates (93%), whereas CTX-M-15 plus TEM were present in clinical and stool non-ST131 E. coli isolates. Using MLST, we confirmed the presence of two NDM-1-positive ST131 E. coli isolates. The aggregate bioscores (metabolite utilization) for ST131, clinical non-ST131, and stool non-ST131 E. coli isolates were 53%, 52%, and 49%, respectively. The ST131 isolates were moderate biofilm producers and were more highly virulent in zebra fish than non-ST131 isolates. According to ERIC-based fingerprinting, the ST131 strains were more genetically similar, and this was subsequently followed by the genetic similarity of clinical non-ST131 and stool non-ST131 E. coli strains. In conclusion, our data provide novel insights into aspects of the fitness advantage of E. coli lineage ST131 and suggest that a number of factors are likely involved in the worldwide dissemination of and infections due to ST131 E. coli isolates.

Matched MeSH terms: Escherichia coli Infections/microbiology; Escherichia coli Infections/mortality; Escherichia coli Infections/veterinary*
Evaluation of the efficacy of chitosan nanoparticles loaded ΦKAZ14 bacteriophage in the biological control of colibacillosis in chickens

Kaikabo AA, AbdulKarim SM, Abas F

Poult Sci, 2017 Feb 01;96(2):295-302.
PMID: 27702916 DOI: 10.3382/ps/pew255

Disease inflicted by avian pathogenic Escherichia coli (APEC) causes economic losses and burden to the poultry industry worldwide. In this study, the efficacy of chitosan nanoparticles loaded ΦKAZ14 (C-ΦKAZ14 NPs) as an oral biological therapy for Colibacillosis was evaluated. C-ΦKAZ14 NPs containing 10(7) PFU/ml of ΦKAZ14 (Myoviridae; T4-like coliphage) bacteriophage were used to treat experimentally APEC-infected COBB 500 broiler chicks. C-ΦKAZ14 NPs and ΦKAZ14 bacteriophage were administered orally in a single dose. The clinical symptoms, mortality, and pathology in the infected birds were recorded and compared with those of control birds that did not receive C-ΦKAZ14 NPs or naked ΦKAZ14 bacteriophage. The results showed that C-ΦKAZ14 NP intervention decreased mortality from 58.33 to 16.7% with an increase in the protection rate from 42.00 to 83.33%. The bacterial colonization of the intestines of infected birds was significantly higher in the untreated control than in the C-ΦKAZ14 NP-treated group (2.30×10(9) ± 0.02 and 0.79×10(3) ± 0.10 CFU/mL, respectively) (P ≤ 0.05). Similarly, a significant difference in the fecal shedding of Escherichia coli was observed on d 7 post challenge between the untreated control and the C-ΦKAZ14 NP-treated group (2.35×10(9) ± 0.05 and 1.58×10(3) ± 0.06 CFU/mL, respectively) (P ≤ 0.05). Similar trends were observed from d 14 until d 21 when the experiment was terminated. Treatment with C-ΦKAZ14 NPs improved the body weights of the infected chicks. A difference in body weight on d 7 post challenge was observed between the untreated control and the C-ΦKAZ14 NP-treated group (140 ± 20 g and 160 ± 20 g, respectively). The increase was significant (P ≤ 0.05) on d 21 between the 2 groups (240 ± 30 g and 600 ± 80 g, respectively). Consequently, the clinical signs and symptoms were ameliorated upon treatment with C-ΦKAZ14 NPs compared with infected untreated birds. In all, based on the results, it can be concluded that the encapsulation of bacteriophage could enhance bacteriophage therapy and is a valuable approach for controlling APEC infections in poultry.

Matched MeSH terms: Escherichia coli Infections
Fulltext Studies on properties of rice straw/polymer nanocomposites based on polycaprolactone and Fe₃O₄ nanoparticles and evaluation of antibacterial activity

Khandanlou R, Ahmad MB, Shameli K, Saki E, Kalantari K

Int J Mol Sci, 2014;15(10):18466-83.
PMID: 25318051 DOI: 10.3390/ijms151018466

Modified rice straw/Fe3O4/polycaprolactone nanocomposites (ORS/Fe3O4/ PCL-NCs) have been prepared for the first time using a solution casting method. The RS/Fe3O4-NCs were modified with octadecylamine (ODA) as an organic modifier. The prepared NCs were characterized by using X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR). The XRD results showed that as the intensity of the peaks decreased with the increase of ORS/Fe3O4-NCs content in comparison with PCL peaks, the Fe3O4-NPs peaks increased from 1.0 to 60.0 wt. %. The TEM and SEM results showed a good dispersion of ORS/Fe3O4-NCs in the PCL matrix and the spherical shape of the NPs. The TGA analysis indicated thermal stability of ORS/Fe3O4-NCs increased after incorporation with PCL but the thermal stability of ORS/Fe3O4/PCL-NCs decreased with the increase of ORS/Fe3O4-NCs content. Tensile strength was improved with the addition of 5.0 wt. % of ORS/Fe3O4-NCs. The antibacterial activities of the ORS/Fe3O4/PCL-NC films were examined against Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus) by diffusion method using nutrient agar. The results indicated that ORS/Fe3O4/PCL-NC films possessed a strong antibacterial activity with the increase in the percentage of ORS/Fe3O4-NCs in the PCL.

Matched MeSH terms: Escherichia coli Infections/drug therapy
Fulltext Polymerase chain reaction-restriction fragment length polymorphism method for differentiation of uropathogenic specific protein gene types

Lai YM, Zaw MT, Shamsudin SB, Lin Z

J Microbiol Immunol Infect, 2016 Aug;49(4):591-4.
PMID: 26212311 DOI: 10.1016/j.jmii.2015.06.002

The putative pathogenicity island (PAI) containing the uropathogenic specific protein (usp) gene and three small open reading frames (orfU1, orfU2, and orfU3) encoding 98, 97, and 96 amino acid proteins is widely distributed among uropathogenic Escherichia coli (UPEC) strains. This PAI was designated as PAIusp. Sequencing analysis of PAIusp has revealed that the usp gene can be divided into two types - uspI and uspII - based on sequence variation at the 3' terminal region and the number and position of orfUs differ from strain to strain. Based on usp gene types and orfU sequential patterns, PAIusp can be divided into four subtypes. Subtyping of PAIusp is a useful method to characterize UPEC strains. In this study, we developed a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to differentiate usp gene types. This method could correctly identify the usp gene type in usp-positive UPEC strains in our laboratory.

Matched MeSH terms: Escherichia coli Infections/microbiology
Fulltext Population dynamics of an Escherichia coli ST131 lineage during recurrent urinary tract infection

Forde BM, Roberts LW, Phan MD, Peters KM, Fleming BA, Russell CW, et al.

Nat Commun, 2019 08 13;10(1):3643.
PMID: 31409795 DOI: 10.1038/s41467-019-11571-5

Recurrent urinary tract infections (rUTIs) are extremely common, with ~ 25% of all women experiencing a recurrence within 1 year of their original infection. Escherichia coli ST131 is a globally dominant multidrug resistant clone associated with high rates of rUTI. Here, we show the dynamics of an ST131 population over a 5-year period from one elderly woman with rUTI since the 1970s. Using whole genome sequencing, we identify an indigenous clonal lineage (P1A) linked to rUTI and persistence in the fecal flora, providing compelling evidence of an intestinal reservoir of rUTI. We also show that the P1A lineage possesses substantial plasmid diversity, resulting in the coexistence of antibiotic resistant and sensitive intestinal isolates despite frequent treatment. Our longitudinal study provides a unique comprehensive genomic analysis of a clonal lineage within a single individual and suggests a population-wide resistance mechanism enabling rapid adaptation to fluctuating antibiotic exposure.

Matched MeSH terms: Escherichia coli Infections/microbiology*
Fulltext Genome sequence of multidrug-resistant Escherichia coli EC302/04, isolated from a human tracheal aspirate

Ho WS, Gan HM, Yap KP, Balan G, Yeo CC, Thong KL

J Bacteriol, 2012 Dec;194(23):6691-2.
PMID: 23144425 DOI: 10.1128/JB.01804-12

Escherichia coli is an important etiologic agent of lower respiratory tract infections (LRTI). Multidrug-resistant E. coli EC302/04 was isolated from a tracheal aspirate, and its genome sequence is expected to provide insights into antimicrobial resistance as well as adaptive and virulence mechanisms of E. coli involved in LRTI.

Matched MeSH terms: Escherichia coli Infections/microbiology
Fulltext The complete genome sequence of Escherichia coli EC958: a high quality reference sequence for the globally disseminated multidrug resistant E. coli O25b:H4-ST131 clone

Forde BM, Ben Zakour NL, Stanton-Cook M, Phan MD, Totsika M, Peters KM, et al.

PLoS One, 2014;9(8):e104400.
PMID: 25126841 DOI: 10.1371/journal.pone.0104400

Escherichia coli ST131 is now recognised as a leading contributor to urinary tract and bloodstream infections in both community and clinical settings. Here we present the complete, annotated genome of E. coli EC958, which was isolated from the urine of a patient presenting with a urinary tract infection in the Northwest region of England and represents the most well characterised ST131 strain. Sequencing was carried out using the Pacific Biosciences platform, which provided sufficient depth and read-length to produce a complete genome without the need for other technologies. The discovery of spurious contigs within the assembly that correspond to site-specific inversions in the tail fibre regions of prophages demonstrates the potential for this technology to reveal dynamic evolutionary mechanisms. E. coli EC958 belongs to the major subgroup of ST131 strains that produce the CTX-M-15 extended spectrum β-lactamase, are fluoroquinolone resistant and encode the fimH30 type 1 fimbrial adhesin. This subgroup includes the Indian strain NA114 and the North American strain JJ1886. A comparison of the genomes of EC958, JJ1886 and NA114 revealed that differences in the arrangement of genomic islands, prophages and other repetitive elements in the NA114 genome are not biologically relevant and are due to misassembly. The availability of a high quality uropathogenic E. coli ST131 genome provides a reference for understanding this multidrug resistant pathogen and will facilitate novel functional, comparative and clinical studies of the E. coli ST131 clonal lineage.

Matched MeSH terms: Escherichia coli Infections/microbiology
Fulltext Titanium Dioxide Nanoparticle-Based Interdigitated Electrodes: A Novel Current to Voltage DNA Biosensor Recognizes E. coli O157:H7

Nadzirah Sh, Azizah N, Hashim U, Gopinath SC, Kashif M

PLoS One, 2015;10(10):e0139766.
PMID: 26445455 DOI: 10.1371/journal.pone.0139766

Nanoparticle-mediated bio-sensing promoted the development of novel sensors in the front of medical diagnosis. In the present study, we have generated and examined the potential of titanium dioxide (TiO2) crystalline nanoparticles with aluminium interdigitated electrode biosensor to specifically detect single-stranded E.coli O157:H7 DNA. The performance of this novel DNA biosensor was measured the electrical current response using a picoammeter. The sensor surface was chemically functionalized with (3-aminopropyl) triethoxysilane (APTES) to provide contact between the organic and inorganic surfaces of a single-stranded DNA probe and TiO2 nanoparticles while maintaining the sensing system's physical characteristics. The complement of the target DNA of E. coli O157:H7 to the carboxylate-probe DNA could be translated into electrical signals and confirmed by the increased conductivity in the current-to-voltage curves. The specificity experiments indicate that the biosensor can discriminate between the complementary sequences from the base-mismatched and the non-complementary sequences. After duplex formation, the complementary target sequence can be quantified over a wide range with a detection limit of 1.0 x 10(-13)M. With target DNA from the lysed E. coli O157:H7, we could attain similar sensitivity. Stability of DNA immobilized surface was calculated with the relative standard deviation (4.6%), displayed the retaining with 99% of its original response current until 6 months. This high-performance interdigitated DNA biosensor with high sensitivity, stability and non-fouling on a novel sensing platform is suitable for a wide range of biomolecular interactive analyses.

Matched MeSH terms: Escherichia coli Infections/microbiology

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