Fimbriae of Human Enterotoxigenic Escherichia Coli and Control of their Expression

1991 ◽  
pp. 37-53 ◽  
Author(s):  
Cyril J. Smyth ◽  
Maire Boylan ◽  
Helen M. Matthews ◽  
David C. Coleman
Keyword(s):  
Escherichia Coli ◽  
Enterotoxigenic Escherichia Coli ◽  
And Control

scholarly journals Passive immunity in cattle against enterotoxigenic Escherichia coli: serologic evaluation of a bacterin containing K99 and F41 fimbriae in colostrum of vaccinated females and calf serum

2004 ◽  
Vol 56 (4) ◽  
pp. 425-432
Author(s):  
H.C.P. Figueiredo ◽  
A.P. Lage ◽  
F.N. Pereira Júnior ◽  
R.C. Leite
Keyword(s):  
Escherichia Coli ◽  
Calf Serum ◽  
Vaccine Dose ◽  
Enterotoxigenic Escherichia Coli ◽  
Passive Immunity ◽  
Control Groups ◽  
Humoral Immune ◽  
Pregnant Females ◽  
Commercial Farms ◽  
And Control

A bacterin from enterotoxigenic Escherichia coli (ETEC), containing fimbriae K99 and F41, was produced and its capacity to induce anti-K99 and anti-F41 antibodies in colostrum of vaccinated cows and in calf serum, and the persistence of these antibodies in neonates were determined. Three experiments were performed on two commercial farms. In all experiments animals were allotted randomly to the blocks, each block consisting of two pregnant females (a vaccinated one and a control one) and their respective calves. In experiment A (farm 1), comprised of 18 blocks, the animals received a vaccine dose 30 days before delivery. In experiment B (farm 1), consisted of 26 blocks, the animals received two vaccine doses (60 and 30 days before delivery). In experiment C (farm 2), consisted of 22 blocks, the animals received two vaccine doses (60 and 30 days before delivery). In experiments A and B pregnant cows and heifers were used and colostrum and serum from 24- to 36-hour-old calves were collected. In experiment C, pregnant embryo-recipient heifers were used and colostrum and sera from calves at 7, 14, 28 and 42 days of age were collected. Anti-K99 and anti-F41 antibodies were detected by ELISA using purified K99 and F41 fimbrial antigens. In experiment A no difference between treated and control groups was observed for the concentration of anti-K99 and anti-F41 antibodies in colostrum and calf serum. In experiment B a difference (P<0.001) was observed for colostrum of vaccinated females and for serum of their calves. In experiment C, difference between vaccinated and control animals was observed for colostrum and calf serum at 7, 14, 28 (P<0.001 in all cases) and 42 days of age (P= 0.003). The results showed the efficiency of the bacterin to induce detectable humoral immune response.

scholarly journals A new plasmid carrying mphA causes prevalence of azithromycin resistance in enterotoxigenic Escherichia coli serogroup O6

2020 ◽  
Author(s):  
Ying Xiang ◽  
Feng Wu ◽  
Yinghui Chai ◽  
Lang Yang ◽  
Sai Tian ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Control Measure ◽  
Enterotoxigenic Escherichia Coli ◽  
Surveillance Network ◽  
Severe Diarrhea ◽  
Coverage Analysis ◽  
Rapid Spread ◽  
Resistant Strains ◽  
And Control ◽  
Azithromycin Resistance

Abstract Background: At present, azithromycin has become an effective treatment for severe diarrhea caused by Enterotoxigenic Escherichia coli (ETEC) infection. However, enterobacteria have begun to develop resistance to azithromycin and have attracted attention in recent years. This study conducted to described the emergence of a high proportion of azithromycin-resistant ETEC serogroup O6 strains in Shanghai and to analyzed the mechanisms of azithromycin resistance.Results: Strains from adult diarrhea patients with ETEC serogroup O6 infections were collected by Shanghai Diarrhea Surveillance Network and the Foodborne Surveillance Network from 2016 to 2018. We tested 30 isolates of ETEC O6 serogroup, 26 of which were resistant to azithromycin. Phylogenetic analysis revealed that these ETEC serogroup O6 strains have formed an independent dominant clone. S1-PFGE and southern blotting revealed the presence of the mphA gene on the 103kb plasmid. Illumina and Nanopore sequencing and plasmid coverage analysis further confirmed that azithromycin-resistant strains carried a novel IncFII plasmid harboring mphA and blaTEM-1 resistance genes.Conclusions: This is the first study to report a high proportion of azithromycin resistance in a particular ETEC serogroup due to a specific plasmid carrying mphA. Our findings indicate the rapid spread of azithromycin resistance, highlighting the urgency of stringent surveillance and control measure.

scholarly journals Oral Immunization with a Salmonella typhimurium Vaccine Vector Expressing Recombinant Enterotoxigenic Escherichia coli K99 Fimbriae Elicits Elevated Antibody Titers for Protective Immunity

1998 ◽  
Vol 66 (11) ◽  
pp. 5470-5476 ◽  
Author(s):  
Miguel A. Ascón ◽  
David M. Hone ◽  
Nancy Walters ◽  
David W. Pascual
Keyword(s):  
Escherichia Coli ◽  
Salmonella Typhimurium ◽  
Protective Immunity ◽  
Mononuclear Cells ◽  
Immunoglobulin A ◽  
Oral Immunization ◽  
Enterotoxigenic Escherichia Coli ◽  
Effective Vaccine ◽  
Antibody Titers ◽  
And Control

ABSTRACT Bovine enterotoxigenic Escherichia coli (ETEC) continues to cause mortality in piglets and newborn calves. In an effort to develop a safe and effective vaccine for the prevention of F5+ ETEC infections, a balanced lethalasd + plasmid carrying the complete K99 operon was constructed and designated pMAK99-asd +. Introduction of this plasmid into an attenuated Salmonella typhimurium Δaro Δasd strain, H683, resulted in strain AP112, which stably expresses E. coli K99 fimbriae. A single oral immunization of BALB/c and CD-1 mice with strain AP112 elicited significant mucosal immunoglobulin A (IgA) titers that remained elevated for >11 weeks. IgA and IgG responses in serum specific for K99 fimbriae were also induced, with a prominent IgG1, as well as IgG2a and IgG2b, titer. To assess the derivation of these antibodies, a K99 isotype-specific B-cell ELISPOT analysis was conducted by using mononuclear cells from the lamina propria of the small intestines (LP), Peyer’s patches (PP), and spleens of vaccinated and control BALB/c mice. This analysis revealed elevated numbers of K99 fimbria-specific IgA-producing cells in the LP, PP, and spleen, whereas elevated K99 fimbria-specific IgG-producing cells were detected only in the PP and spleen. These antibodies were important for protective immunity. One-day-old neonates from dams orally immunized with AP112 were provided passive protection against oral challenge with wild-type ETEC, in contrast to challenged neonates from unvaccinated dams or from dams vaccinated with a control Salmonella vector. These results confirm that oral Salmonella vaccine vectors effectively deliver K99 fimbriae to mucosal inductive sites for sustained elevation of IgA and IgG antibodies and for eliciting protective immunity.

Colonization of the Small Intestine of Weaned Pigs by Enterotoxigenic Escherichia coli that Lack Known Colonization Factors

1992 ◽  
Vol 29 (3) ◽  
pp. 239-246 ◽  
Author(s):  
B. Nagy ◽  
L. H. Arp ◽  
H. W. Moon ◽  
T. A. Casey
Keyword(s):  
Escherichia Coli ◽  
Peyer's Patches ◽  
Enterotoxigenic Escherichia Coli ◽  
Peyer’S Patches ◽  
Bacterial Cells ◽  
Weaned Pigs ◽  
Electron Microscopic ◽  
Etec Strain ◽  
Fimbrial Adhesins ◽  
And Control

Intestinal colonization of 3-week-old weaned pigs by enterotoxigenic Escherichia coli (ETEC) strains that were originally isolated from weaned pigs with fatal diarrhea and that lacked K88, K99, F41, and 987P adhesins (4P− ETEC) was studied by histologic, immunofluorescent, and electron microscopic techniques. In the first experiment, 16 principal pigs were inoculated orogastrically with ETEC strain 2134 (serogroup 0157:H19) or 2171 (serogroup 0141:H4), and eight control pigs were not inoculated. In the second experiment, 24 principals were inoculated with ETEC strain 2134, and 12 controls were inoculated with a nonenterotoxigenic strain of E. coli. Principal and control pigs were necropsied at intervals from 24 to 72 hours after inoculation of principals to provide the tissues used for this report. Results from the two experiments and with both ETEC strains were similar and therefore were combined. Adhesion by 4P″ ETEC was demonstrated in ileum but not in cecum or colon in 22/40 principal pigs sampled at 24 to 72 hours after orogastric inoculation. Adherent bacteria were most apparent on the intestinal villi covering Peyer's patches. Only occasional adherent bacteria were detected in ileal sections from a few (4/20) of the control pigs. Adherence by 4P− ETEC was characterized by “patches” of bacteria closely associated with the lateral surfaces and less frequently with the tips and the bases of intact villi. In most cases, the adherent bacteria were separated from epithelial cell microvilli and other bacterial cells by a 50–400-nm space. Filamentous bacterial appendages bridged this space and formed a network among adjacent bacteria. Colonization of weaned pigs by the 4P− ETEC strains was characterized by preferential adhesion of bacteria to the villi covering Peyer's patches. The filamentous appendages observed between bacteria and microvilli are previously unrecognized fimbrial adhesins, which mediate colonization by these ETEC.

Study effect of crude extracts of Hibiscus sabdarifa L. on some Enterobacteriaceae

2018 ◽  
Vol 9 (SPL1) ◽  
Author(s):  
Sabreen A Kamal ◽  
Ishraq A Salih ◽  
Hawraa Jawad Kadhim ◽  
Zainab A Tolaifeh
Keyword(s):  
Escherichia Coli ◽  
Ethyl Acetate ◽  
Bacterial Growth ◽  
Chemical Compounds ◽  
Inhibition Zone ◽  
Crude Extracts ◽  
And Control

Red rose or roselle (beauty rose ) is natively known as red tea belong to Malvaceae, it is flowers use traditionally for antihypertensive hepato protective, anticancer,antidiabetic,antibacterial, cytotoxicity and antidiarreal, By preparing red tea from it's flower. In this study, we extract chemical compounds by using two solvent which are Ethanol, Ethyl acetate. so we can extract Anthocyanin which is responsible for red colour of flower with many chemical compounds. then study the effect of these extracts on 5 genera from Enterobacteriacaea which can cause diarrheae (Shigella, Salmonella, Escherichia coli, Proteus and Klebsiella ) by preparing 3 concentrations for each solvent (250, 500, 750 ) mg/ml, and control then compare with two antibiotic (Azereonam 30 mg/ml and Bacitracin 10 mg/ml ) these extracts revealed obvious inhibition zone in bacterial growth.

scholarly journals Structure of the master regulator Rns reveals an inhibitor of enterotoxigenic Escherichia coli virulence regulons

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Charles R. Midgett ◽  
Kacey Marie Talbot ◽  
Jessica L. Day ◽  
George P. Munson ◽  
F. Jon Kull
Keyword(s):  
Escherichia Coli ◽  
Small Molecules ◽  
Family Member ◽  
Shigella Flexneri ◽  
Decanoic Acid ◽  
Enterotoxigenic Escherichia Coli ◽  
Gram Negative Bacteria ◽  
Enteric Infections ◽  
First Time ◽  
Arac Family

AbstractEnteric infections caused by the gram-negative bacteria enterotoxigenic Escherichia coli (ETEC), Vibrio cholerae, Shigella flexneri, and Salmonella enterica are among the most common and affect billions of people each year. These bacteria control expression of virulence factors using a network of transcriptional regulators, some of which are modulated by small molecules as has been shown for ToxT, an AraC family member from V. cholerae. In ETEC the expression of many types of adhesive pili is dependent upon the AraC family member Rns. We present here the 3 Å crystal structure of Rns and show it closely resembles ToxT. Rns crystallized as a dimer via an interface similar to that observed in other dimeric AraC’s. Furthermore, the structure of Rns revealed the presence of a ligand, decanoic acid, that inhibits its activity in a manner similar to the fatty acid mediated inhibition observed for ToxT and the S. enterica homologue HilD. Together, these results support our hypothesis that fatty acids regulate virulence controlling AraC family members in a common manner across a number of enteric pathogens. Furthermore, for the first time this work identifies a small molecule capable of inhibiting the ETEC Rns regulon, providing a basis for development of therapeutics against this deadly human pathogen.

scholarly journals High prevalence of qnrA and qnrB genes among fluoroquinolone-resistant Escherichia coli isolates from a tertiary hospital in Southern Nigeria

2021 ◽  
Vol 45 (1) ◽  
Author(s):  
Chibuzor M. Nsofor ◽  
Mirabeau Y. Tattfeng ◽  
Chijioke A. Nsofor
Keyword(s):  
Escherichia Coli ◽  
Susceptibility Testing ◽  
Tertiary Hospital ◽  
Vaginal Swab ◽  
Fluoroquinolone Resistance ◽  
E Coli ◽  
Diffusion Technique ◽  
High Prevalence ◽  
Polymerase Chain ◽  
And Control

Abstract Background This study was aimed to determine the prevalence of qnr genes among fluoroquinolone-resistant Escherichia coli (FREC) isolates from Nigeria. Antimicrobial susceptibility testing was performed by disc diffusion technique. Polymerase chain reaction was used to identify Escherichia coli (E. coli) and for the detection of qnr genes. Results A total of 206 non-duplicate E. coli were isolated from 300 clinical specimens analyzed. In all, 30 (14.6%) of these isolates were FREC; the resistance to fluoroquinolones among these 30 FREC showed 80% (24), 86.7% (26), 86.7% (26), 100% (30), 86.7% (26), 93.3% (28) and 86.7% (26) were resistant to pefloxacin, ciprofloxacin, sparfloxacin, levofloxacin, nalidixic acid, ofloxacin and moxifloxacin, respectively. The distribution of FREC among the various sample sources analyzed showed that 14%, 10%, 13.3%, 16.7% and 20% of the isolates came from urine, stool, high vaginal swab, endo cervical swab and wound swab specimens, respectively. More FREC were isolated from female samples 73.3% (22) compared to male samples 26.7% (8) and were more prevalent among the age group 26–35 years (40%). Twenty eight out of the 30 (93.3%) FREC isolates possessed at least one fluoroquinolone resistance gene in the form of qnrA 10 (33.3%) and qnrB 18 (60%), respectively; qnrS was not detected among the FREC isolates analyzed and 13.5% of the isolates possessed both the qnrA and qnrB genes. Phylogenetic analysis showed that these isolates were genetically diverse. Conclusions These findings suggest a possible resistance to fluoroquinolone is of high interest for better management of patients and control of antimicrobial resistance in Nigeria.

Bacteriophages reduce Escherichia coli O157:H7 levels in experimentally inoculated sheep

2009 ◽  
Vol 89 (2) ◽  
pp. 285-293 ◽  
Author(s):  
S J Bach ◽  
R P Johnson ◽  
K. Stanford ◽  
T A McAllister
Keyword(s):  
Escherichia Coli ◽  
Oral Administration ◽  
Coliform Bacteria ◽  
Escherichia Coli O157 ◽  
Fecal Shedding ◽  
Total Coliforms ◽  
E Coli ◽  
Oral Inoculation ◽  
Experimental Treatments ◽  
And Control

Bacteriophage biocontrol has potential as a means of mitigating the prevalence of Escherichia coli O157:H7 in ruminants. The efficacy of oral administration of bacteriophages for reducing fecal shedding of E. coli O157:H7 by sheep was evaluated using 20 Canadian Arcott rams (50.0 ± 3.0) housed in four rooms (n = 5) in a contained facility. The rams had ad libitum access to drinking water and a pelleted barley-based total mixed ration, delivered once daily. Experimental treatments consisted of administration of E. coli O157:H7 (O157), E. coli O157:H7+bacteriophages (O157+phage), bacteriophages (phage), and control (CON). Oral inoculation of the rams with 109 CFU of a mixture of four nalidixic acid-resistant strains of E. coli O157:H7 was performed on day 0. A mixture of 1010 PFU of bacteriophages P5, P8 and P11 was administered on days -2, -1, 0, 6 and 7. Fecal samples collected on 14 occasions over 21 d were analyzed for E. coli O157:H7, total E. coli, total coliforms and bacteriophages. Sheep in treatment O157+phage shed fewer (P < 0.05) E. coli O157:H7 than did sheep in treatment O157. Populations of total coliforms and total E. coli were similar (P < 0.05) among treatments, implying that bacteriophage lysis of non-target E. coli and coliform bacteria in the gastrointestinal tract did not occur. Bacteriophage numbers declined rapidly over 21 d, which likely reduced the chance of collision between bacteria and bacteriophage. Oral administration of bacteriophages reduced shedding of E. coli O157:H7 by sheep, but a delivery system that would protect bacteriophages during passage through the intestine may increase the effectiveness of this strategy as well as allow phage to be administered in the feed.Key words: Escherichia coli O157:H7, bacteriophage, sheep, environment, coliforms

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