scholarly journals Isolation and characterization of Escherichia coli serotype O157:H7 and other verotoxin-producing E. coli in healthy Indian cattle

2020 ◽  
Vol 13 (10) ◽  
pp. 2269-2274
Author(s):  
Dasharath B. Shinde ◽  
Surbhi Singhvi ◽  
Santosh S. Koratkar ◽  
Sunil D. Saroj

Background and Aim: Cattle are the main reservoir of Escherichia coli O157:H7 and other verotoxigenic E. coli (VTEC); therefore, there is an increased risk of infection to humans by either direct or indirect mode of transmissions. However, the prevalence of E. coli O157:H7 in the healthy cattle population of India is yet to be ascertained. This study aimed to screen the dairy cattle in and around Pune, Maharashtra, India, for verotoxin-producing E. coli O157:H7. Materials and Methods: A total of 257 rectal swabs were collected from 15 different organized and unorganized dairy farms of Pune during the period, January-March 2015. The screening involved enrichment in EC broth followed by differential identification on MacConkey sorbitol agar. The presumptive positive isolates were further confirmed by multiplex polymerase chain reaction (PCR) using primers specific to rfbE (O157), fliC (H7), VT1 (MK1), and VT2 (MK2). Vero-toxicity and antibiotic sensitivity were examined in PCR confirmed isolates. Results: Out of the 257 samples analyzed, 1.9% (2/105) were positive for O157:H7 and 39% (41/105) were positive for VTEC. Two PCR confirmed positive O157:H7 strains and two randomly selected PCR-positive VT strains exhibited in vitro cytopathic effect on Vero cells on day-7 post-inoculation. Antibiotic sensitivity profiling of O157:H7 strains exhibited resistance against penicillin G, kanamycin, ampicillin, tetracycline, gentamycin, cefotaxime, streptomycin, and piperacillin. Conclusion: These findings reveal the presence of pathogenic E. coli O157:H7 in the healthy cattle of Pune; in a situation, wherein regular surveillance for O157:H7 is not a norm. Therefore, the findings presented herein warrant routine surveillance and public awareness to prevent the transfer of such pathogens and manage health risks to the public.

1970 ◽  
Vol 8 (1) ◽  
pp. 23-26 ◽  
Author(s):  
SK Paul ◽  
MSR Khan ◽  
MA Rashid ◽  
J Hassan ◽  
SMS Mahmud

The research works was conducted with a view to isolate and identify the Escherichia coli (E. coli) organism from diarrhoeic cases of buffalo reared in selected areas of Bangladesh as well the prevalence and antibiotic sensitivity pattern of the isolated E. coli in the Department of Microbiology and Hygiene, Bangladesh Agricultural University (BAU), Mymensingh-2202 during the period from April 2008 to May 2009. A total of 50 rectal swab samples were collected from 4 different places namely Haluaghat and Boira of Mymensingh, Madupur of Tangail and Kazipur of Sirajgonj districts. The samples were aseptically carried to the laboratory of the Department of Microbiology and Hygiene and subjected to different cultural, morphological and biochemical examinations. Upon cultural, morphological and biochemical examinations 23 (45%) samples were found to be positive for E. coli. The highest prevalence was found in Haluaghat, Mymensingh (53.33%) and the lowest (40.00%) in Boira, Mymensingh and Kazipur, Sirajganj. Antibiogram study revealed that the isolated E. coli was highly sensitive to Enrofloxacin and Ciprofloxacin, moderately sensitive to Cefalexin and Amoxicillin, and resistant to Nalidixic acid and Erythromycin. DOI = 10.3329/bjvm.v8i1.7398 Bangl. J. Vet. Med. (2010). 8(1): 23-26


1970 ◽  
Vol 2 (2) ◽  
pp. 99-102 ◽  
Author(s):  
MA Rahman ◽  
MA Samad ◽  
MB Rahman ◽  
SML Kabir

Avian salmonellosis (AS), avian colibacillosis (AC) and avian pasteurellosis (AP) have been recognized as important bacterial diseases in poultry associated with morbidity and mortality in Bangladesh. The causative agents of these three diseases were isolated (5 isolates / disease) from dead chickens submitted for diagnosis at the BRAC Poultry Disease Diagnostic Centre, Gazipur during the period from January to December 2002. Five isolates of each of the Salmonella pullorum, Escherichia coli and Pasteurella multocida were evaluated against eight antibiotic containing disc which included ciprofloxacin, gentamicin, ampicillin, chloramphenicol, erythromycin, tetracycline, cephradine and penicillin G. Erythromycin in S. pullorum and Ciprofloxacin both in the E. coli and P. multocida were found highest sensitive, gentamicin, chloramphenicol, cephradine were found moderately sensitive to S. pullorum, gentamicin, tetracycline, erythromycin and ampicillin were found moderately sensitive to E. coli, and gentamicin ampicillin, cephradine and penicillin G were moderately sensitive to P. multocida. Therapeutic trials against experimentally produced S. pullorum, E. coli and P. multocida infection in three groups of broiler chickens showed that cephradine against S. pullorum and ciprofloxacin against both in E. coli and P. multocida were found highly effective both in vitro and in vivo studies, therefore, cephradine against salmonellosis and ciprofloxacin against colibacillosis and pasteurellosis are effective drugs of choice which could be used to control morbidity and mortality in poultry caused by these diseases.Key words: antibiotic sensitivity; salmonellosis; colibacillosis; pasteurellosis, broiler chickensdoi: 10.3329/bjvm.v2i2.2538Bangl. J. Vet. Med. (2004). 2 (2): 99-102


Genetics ◽  
1991 ◽  
Vol 127 (1) ◽  
pp. 21-30 ◽  
Author(s):  
S K Whoriskey ◽  
M A Schofield ◽  
J H Miller

Abstract Using site-specific mutagenesis in vitro we constructed a genetic system to detect mutants with altered rates of deletion formation between short repeated sequences in Escherichia coli. After in vivo mutagenesis with chemical mutagens and transposons, the system allowed the identification of mutants with either increased or decreased deletion frequencies. One mutational locus, termed mutR, that results in an increase in deletion formation, was studied in detail. The mutR gene maps at 38.5 min on the E. coli genetic map. Since the precise excision of many transposable elements is also mediated at short repeated sequences, we investigated the effects of the mutant alleles, as well as recA, on precise excision of the transposon Tn9. Neither mutR nor recA affect precise excision of the transposon Tn9, from three different insertions in lacI, whereas these alleles do affect other spontaneous deletions in the same system. These results indicate that deletion events leading to precise excision occur principally via a different pathway than other random spontaneous deletions. It is suggested that, whereas precise excision occurs predominantly via a pathway involving replication enzymes (for instance template strand slippage), deletions on an F'factor are stimulated by recombination enzymes.


2016 ◽  
Vol 15 (2) ◽  
pp. 172-177
Author(s):  
Quazi Rubyath Banna ◽  
Badar Uddin Umar ◽  
S M Niazur Rahman ◽  
Tanbira Alam ◽  
Kazi Selim Anwar ◽  
...  

Objective: Medicinal plants remain in vogue to treat some diseases in lower socio-economic communities, despite the availability of antimicrobials, often. Majority of rural Bangladeshi and tribal people being grossly illiterate and ignorant, use various herbs to treat a wide range of diseases. Of several medicinal-plants, neem is reported to have enormous impact in treating inflammation and infections. We, therefore, compared the antimicrobial effect of ethanolic neem leave extract (ENLE) on Escherichia coli (E. coli), with that of Ciprofloxacin. Materials & Methods: This experimental study compared the in vitro antimicrobial activity between ENLE and Ciprofloxacin on E. coli carried out in Department of Pharmacology and Therapeutics of SS-Medical College, Dhaka, Bangladesh. Antimicrobial efficacy of ENLE and ciprofloxacin (5µg; Oxoid, UK) was determined against E. coli following minimum inhibitory concentration. By filtration and evaporation of Neem leaves ENLE was prepared. Antibiotic Sensitivity Test was performed on Muller-Hinton agar using a twofold serial dilution. Results: ENLE showed an inhibitory effect on the growth of E. coli at the concentration of 3.125 mg/ml. Antibacterial susceptibility of E. coli was performed on MHA and diameters of zone of inhibition by both ENLE and Ciprofloxacin were measured after overnight aerobic incubation at 37°C. Diameter of zone of inhibition against E. coli was 28 ± 0.16 mm with ENLE, 36 ± 0.07 mm with Ciprofloxacin (5µg/disk) (p<0.000). Conclusion: Findings of this preliminary in-vitro experiment though suggests that, ENLE against E. coli showed limited efficacy, better efficacy of Ciprofloxacin cannot be ruled out unless further in depth studies elucidates stronger evidences to support it.Bangladesh Journal of Medical Science Vol.15(2) 2016 p.172-177


Genetics ◽  
1979 ◽  
Vol 92 (4) ◽  
pp. 1041-1059
Author(s):  
Joan M Henson ◽  
Herman Chu ◽  
Carleen A Irwin ◽  
James R Walker

ABSTRACT Escherichia coli mutants with temperature-sensitive (ts) mutations in dnaX and dnaY genes have been isolated. Based on transduction by phage PI, dnaX and Y have been mapped at minutes 10.4-10.5 and 12.1, respectively, in the sequence dnaX purE dnaY. Both dnaXts36 and YtslO are recessive to wild-type alleles present on episomes. F13 carries both dnaX  + and Y  +; the shorter F210 carries dnaY  +, but not X  +. Lambda transducing phages that carry dnaX  + or Y  + have been isolated, and hybrid plasmids of Col E1 and E. coli DNA from the CLARKE and CARBON (1976) collection also carry portions of the dnaX purE dnaY region. Results obtained with the λ transducing phages and the hybrid plasmids suggest that dnaX is a different gene from the previously characterized dnaZ gene, which is also near minute 10.5.—The dnaXts36 mutant, after a shift to 42°, stopped DNA synthesis gradually, and the total amount of DNA increased two-fold. When this mutant was shifted to M°, the rate of DNA synthesis dropped immediately and the final increment of DNA was only 10% of the initial amount. Replicative DNA synthesis in toluene-treated cells was completely inhibited at 42° and was partially in-hibited even at 30°.—When the dnaYtslO mutant was shifted to 42°, DNA synthesis gradually stopped, and the amount of DNA increased 3.6-fold. At 44°, residual DNA synthesis amounted to a two-fold increase. Replicative DNA synthesis in vitro in toluene-treated cells was inactivated after 20 minutes at 42° or by "preincubation" of cells at 42° before toluene treatment.— The dnaX and dnaY products probably function in polymerization of DNA, although participation also in initiation cannot be excluded.


2014 ◽  
Vol 2 (1) ◽  
pp. 15-18
Author(s):  
Kohinoor Parvin ◽  
Nahid Rahman ◽  
M Mostafizur Rahman ◽  
M Alimul Islam

The research work was conducted to isolate & characterized the bacteria isolated from mid-stream urine of human. A total of 30 samples were collected from patients with urinary tract infection (n=10samples); diabetic patients (n=10samples) & apparently healthy individuals (n=10samples). Escherichia coli, Staphylococcus spp. and Bacillus spp. was the predominant bacterial flora of human urine. Among the isolates, the prevalence of Escherichia coli was highest (80%) compared to Staphylococcus spp.(14%) and Bacillus spp.(6%). E. coli isolated from 6 different sources were found to be highly virulent, moderately virulent, less virulent and avirulent categories as observed in day-old suckling mice. Antibiotic sensitivity profiles suggest that nalidixic acid will be the first drugs of choice to treat the UTI caused by E. coli and arythromycin, ampicillin and azithromycin will be the second drugs of choice to treat the UTI caused by Staphylococcus spp and Bacillus spp. respectively. Microbes and Health, June 2013, 2(1): 15-18DOI: http://dx.doi.org/10.3329/mh.v2i1.17257


2011 ◽  
Vol 77 (8) ◽  
pp. 2611-2616 ◽  
Author(s):  
Kwang Cheol Jeong ◽  
Min Young Kang ◽  
Jihun Kang ◽  
David J. Baumler ◽  
Charles W. Kaspar

ABSTRACTEnterohemorrhagicEscherichia coliO157:H7 (EHEC) is a significant human pathogen that resides in healthy cattle. It is thought that a reduction in the prevalence and numbers of EHEC in cattle will reduce the load of EHEC entering the food chain. To this end, an intervention strategy involving the addition of chitosan microparticles (CM) to feed in order to reduce the carriage of this pathogen in cattle was evaluated. Experiments with individual Holstein calves and a crossover study found that the addition of CM to feed decreasedE. coliO157:H7 shedding. In the crossover study, CM resulted in statistically significant reductions in the numbers recovered from rectal swab samples (P< 0.05) and the duration of shedding (P< 0.05). The effects of feeding CM to calves differed, indicating that the optimal levels of CM may differ between animals or that other factors are involved in the interaction between CM andE. coliO157:H7.In vitrostudies demonstrated thatE. coliO157:H7 binds to CM, suggesting that the reduction in shedding may result at least in part from the binding of positively charged CM to negatively chargedE. colicells. Additional studies are needed to determine the impact of CM feeding on animal production, but the results from this study indicate that supplementing feed with CM reduces the shedding ofE. coliO157:H7 in cattle.


2018 ◽  
Vol 55 (4) ◽  
pp. 390-396 ◽  
Author(s):  
Roger Lafontaine Mesquita TABORDA ◽  
Luiz Antônio da SILVA ◽  
Patricia Puccinelli ORLANDI ◽  
Flávia Serrano BATISTA ◽  
Renata Santos RODRIGUES ◽  
...  

ABSTRACT BACKGROUND: Enteroaggregative Escherichia coli (EAEC) is one of the main acute and chronic diarrhea causes both in children and adults, mainly in developing countries. OBJECTIVE: The aim of the present study is to characterize EAEC strains isolated from faecal samples and to identify genes potentially contributing to virulence, biofilm production and antimicrobial resistance in children admitted to a pediatric hospital in Porto Velho, Rondônia State. METHODS: The total of 1,625 E. coli specimens were isolated from 591 children in the age group 6 years or younger who were hospitalized in Cosme and Damião Children Hospital in Porto Velho, between February 2010 and February 2012, with acute gastroenteritis. Colonies suggestive of E. coli were subjected to polymerase chain reaction testing in order to identify the virulence factors. The in vitro adhesion assays using HEp-2 adherence were tests. Biofilm detection through spectrophotometry and antimicrobial susceptibility tests were conducted in the disk diffusion method. RESULTS: The mentioned study examined 591 stool samples from children with diarrhea. Diarrheogenic E. coli was found in 27.4% (162/591) of the children. EAEC was the diarreagenic E. coli most frequently associated with diarrhea 52.4% (85/162), which was followed by enteropathogenic E. coli 43.8% (71/162), enterotoxigenic E. coli 2.4% (4/162), and enterohemorrhagic E. coli 1.2% (2/162). The aggR gene was detected in 63.5% (54/85) of EAEC isolates; moreover, statistically significant correlation was observed among typical EAEC (aggR) and aatA (P<0.0001), irp2 (P=0.0357) and shf (P=0.0328). It was recorded that 69% (59/85) of the 85 analyzed EAEC strains were biofilm producers; 73% (43/59) of the biofilm producers carried the aggR gene versus 42.3% (11/26) of non-producers (P=0.0135). In addition, there was association between the aatA gene and biofilm production; 61% (36/59) of the samples presented producer strains, versus 19.2% (5/26) of non-producers (P<0.0004). Antibiotic sensitivity test evidenced that most EAEC were ampicillin 70.6% (60/85), sulfamethoxazole 60% (51/85), tetracycline 44.7% (38/85) and cefotaxime 22.4% (19/85) resistant. CONCLUSION: As far as it is known, the present study is pioneer in Northern Brazil to investigate EAEC virulence factors and to show the antimicrobial susceptibility of EAEC strains isolated from children with diarrhea.


2006 ◽  
Vol 72 (9) ◽  
pp. 6405-6410 ◽  
Author(s):  
Raul R. Raya ◽  
Peter Varey ◽  
Rebecca A. Oot ◽  
Michael R. Dyen ◽  
Todd R. Callaway ◽  
...  

ABSTRACT Bacteriophage CEV1 was isolated from sheep resistant to Escherichia coli O157:H7 colonization. In vitro, CEV1 efficiently infected E. coli O157:H7 grown both aerobically and anaerobically. In vivo, sheep receiving a single oral dose of CEV1 showed a 2-log-unit reduction in intestinal E. coli O157:H7 levels within 2 days compared to levels in the controls.


2008 ◽  
Vol 54 (12) ◽  
pp. 984-995 ◽  
Author(s):  
Danica Baines ◽  
Byron Lee ◽  
Tim McAllister

In the last decade, Escherichia coli O157:H7 have emerged as important pathogens of the gastrointestinal tract of humans. Healthy cattle have been identified as the primary reservoir, however, the factors affecting heterogeneous E. coli O157:H7 fecal shedding are not fully understood. The aim of this study was to investigate the contribution of E. coli O157:H7 colonization of small and large intestinal sites to the heterogeneity of fecal shedding in cattle. There was a dose-dependant E. coli O157:H7 E318N colonization of duodenum, jejunum, ileum, cecum, ascending colon, spiral colon, descending colon, and the rectoanal junction in vitro with no difference in E. coli O157:H7 colonization of the rectoanal junction and other intestinal sites. There were 10–100 times greater E. coli O157:H7 colonization of intestinal sites from persistent shedding cattle compared with nonpersistent shedding cattle. Novel pathologies were associated with E. coli O157:H7 colonization sites in the small and large intestine. The first pathology, focal petechiae, was present throughout the intestinal tract of cattle that ceased shedding E. coli O157:H7 for 5–12 weeks or in the jejunum, ileum, cecum, and ascending colon of cattle shedding E. coli O157:H7 for 4–5 months. The second pathology, mucosal hemorrhages, was present in the same sites as the focal petechiae in cattle shedding for 5 months and these hemorrhages were in the final stages of repair. Several features of these hemorrhages support this conclusion including the brown appearance, low amount of classic E. coli O157:H7 induced A/E lesions, flattened epithelium, and blunted villi. Although mucosal hemorrhages were present in the jejunum, ileum, cecum, and ascending colon in cattle shedding for 4 months, many other pathologies were also present that were indicative of hemorrhagic enteritis as evidenced by the blood red appearance of hemorrhages, severe edema, and dark red erythema. Escherichia coli O157:H7 were associated with both pathologies suggesting it is the causative agent. The current study supports a relationship between the amount of E. coli O157:H7 colonization in intestinal sites and heterogeneous fecal shedding by cattle.


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