scholarly journals Genetic Structure of the nadA and nadB Antivirulence Loci in Shigella spp.

2007 ◽  
Vol 189 (17) ◽  
pp. 6482-6486 ◽  
Author(s):  
Anne-Laure Prunier ◽  
Raymond Schuch ◽  
Reinaldo E. Fernández ◽  
Anthony T. Maurelli
Keyword(s):  
Escherichia Coli ◽  
Genetic Structure ◽  
Nicotinic Acid ◽  
E Coli ◽  
Shigella Spp

ABSTRACT Comparison of nadA and nadB in 14 Shigella strains and enteroinvasive Escherichia coli versus E. coli showed that at least one locus is altered in all strains. These observations explain the characteristic nicotinic acid auxotrophy of Shigella organisms and are consistent with the previously identified antivirulence nature of these genes for these pathogens.

scholarly journals PCR for Detection of Shigella spp. in Mayonnaise

1998 ◽  
Vol 64 (4) ◽  
pp. 1242-1245 ◽  
Author(s):  
Eduardo Villalobo ◽  
Antonio Torres
Keyword(s):  
Escherichia Coli ◽  
Genomic Dna ◽  
Shigella Dysenteriae ◽  
Gene Fragment ◽  
Amplification Product ◽  
E Coli ◽  
16S Ribosomal Dna ◽  
Shigella Spp ◽  
Dna Primers ◽  
Sensitive Method

ABSTRACT The use of PCR to amplify a specific virA gene fragment serves as a highly specific and sensitive method to detect virulent bacteria of the genus Shigella and enteroinvasiveEscherichia coli. Amplification of a 215-bp DNA band was obtained by using isolated genomic DNA of Shigella, individual cells of Shigella dysenteriae, and mayonnaise contaminated with S. dysenteriae. Moreover, a multiplex PCR with specific (virA) and bacterium-restricted (16S ribosomal DNA) primers generated an amplification product of approximately 755 bp for all bacteria tested and an additional 215-bp product for Shigella and enteroinvasive E. coli.

scholarly journals Frequency of Antimicrobial Resistant Bacteria in Broiler Meat

2021 ◽  
Vol 78 (2) ◽  
pp. 44
Author(s):  
Alina L. NISTOR ◽  
Mihaela MIHAI ◽  
Ancuța M. ROTAR ◽  
Carmen R. POP
Keyword(s):  
Escherichia Coli ◽  
Resistant Bacteria ◽  
Salmonella Spp ◽  
Broiler Meat ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Level Data ◽  
Shigella Spp ◽  
Resistant Strains ◽  
Antimicrobial Treatments

Antimicrobial resistance (AMR) represents the ability of microorganisms to resist antimicrobial treatments. AMR occurs when microorganisms change in order to reduce or eliminate the effect of antimicrobials, which they were previously susceptible. There were reported animal food products contaminated with antimicrobial resistant strains, like methicillin-resistant Staphylococcus aureus (MRSA), Camylobacter spp., extended spectrum-beta-lactamase (ESBL) producing-Enterobacteriaceae (Salmonella spp., Escherichia coli, Klebsiella spp., Shigella spp. etc.). The aim of this paper is to analyze the frequency of antimicrobial resistant bacteria in broiler meat, at European level. Data were obtained based on the latest EFSA and ECDC Reports, comparing the year 2016 with the year 2018 of the incidence of Salmonella spp., different serovars of Salmonella enterica subs. enterica and Escherichia coli producing ESBL and AmpC, in broiler meat. The incidence of resistant Salmonella spp. showed a decrease between 2016 and 2018. However, the incidence increased for different resistant serovars. Salmonella Infantis showed a decrease in the two years taken into consideration. Regarding the incidence of ESBL E. coli in broiler meat, the results showed an increase for resistance to ceftazidime, ciprofloxacin and ampicillin.

scholarly journals Species and serovars of enteropathogenic agents associated with acute diarrheal disease in Rosario, Argentina

1996 ◽  
Vol 38 (1) ◽  
pp. 5-7 ◽  
Author(s):  
Rodolfo Notario ◽  
Noemi Borda ◽  
Telma Gambande ◽  
Emma Sutich
Keyword(s):  
Escherichia Coli ◽  
Vibrio Cholerae ◽  
Diarrheal Disease ◽  
Enteropathogenic Escherichia Coli ◽  
E Coli ◽  
Frequent Species ◽  
Shigella Spp ◽  
Campylobacter Spp

We report the most frequent species and serovars of enteropathogenic organisms in Rosario from 1985 to 1993. Enteropathogenic Escherichia coli was the most prevalent agent affecting 144/570 (25.2%) children; 0111 represented 41.8%, 055: 13.6%, 0119: 12.7%. Among enterotoxigenic E. coli (ETEC) the most frequent were ETEC-ST 0128:H21 and 0153:H45. Shigella spp were isolated in 8.8%; S.flexneri: 7%, principally type 2 (59.5%); S. sonnei: 1.6%, and S. dysenteriae type 2: 0.2%. Campylobacter spp were found in 6.1% of patients; C.jejuni: 4.6%; C. coli: 1.4% and C. lari: 0.2%; except groups 0 13,50 and 0 4 (2 cases each), no predominant serogroups were found. Salmonella was isolated in 2.8% of cases, being the predominant serovar S. typhimurium until 1986, but a dramatically increase of cases due to S. enteritidis was observed since 1987. There was 1.9% of Aeromonas spp and 2 cases due to Vibrio cholerae non 0-1. No Yersinia was found. In patients with gastroenteritis due to Shigella, Campylobacter, Salmonella, or EPEC as the unique pathogen, leukocytes were observed in the faeces in 70%, 50%, 20%, and 10% of cases respectively.

Coliforms and Prevalence of Escherichia coli and Foodborne Pathogens on Minimally Processed Spinach in Two Packing Plants

2008 ◽  
Vol 71 (12) ◽  
pp. 2398-2403 ◽  
Author(s):  
SANJA ILIC ◽  
JOSEPH ODOMERU ◽  
JEFFREY T. LeJEUNE
Keyword(s):  
Escherichia Coli ◽  
Standard Deviation ◽  
Foodborne Pathogens ◽  
The United States ◽  
Total Coliform ◽  
Minimally Processed ◽  
Minimal Processing ◽  
E Coli ◽  
Fresh Vegetables ◽  
Shigella Spp

Minimally processed spinach has been recently associated with outbreaks of foodborne illnesses. This study investigated the effect of commercial minimal processing of spinach on the coliform and Escherichia coli counts and the prevalence of E. coli O157:H7, Salmonella, Shigella spp., and Listeria monocytogenes on two types of spinach before and after minimal processing. A total of 1,356 spinach samples (baby spinach, n = 574; savoy spinach, n = 782) were collected daily in two processing plants over a period of 14 months. Raw spinach originated from nine farms in the United States and three farms in Canada. Overall, the proportion of samples positive for coliforms increased from 53% before minimal processing to 79% after minimal processing (P < 0.001). Average total coliform counts also increased significantly after processing, especially in baby spinach (mean ± standard deviation, 1.16 ± 0.14 log CFU/g to 2.37 ± 0.08 log CFU/g following processing; P < 0.001). E. coli was isolated from 8.9% of the samples (mean ± standard deviation, 1.81 ± 0.14 log CFU/g), and no difference in prevalence or CFU counts after processing (P < 0.1) was observed. E. coli O157:H7 and Shigella spp. were not isolated from any of the samples. Salmonella and L. monocytogenes were isolated from 0.4 and 0.7% of samples, respectively. Results demonstrate that commercial minimal processing of spinach based on monitored chlorine washing and drying may not decrease microbial load on spinach leaves as expected. Further research is needed to identify the most appropriate measures to control food safety risk under commercial minimal processing of fresh vegetables.

scholarly journals Genetic Structure and Distribution of Four Pathogenicity Islands (PAI I536 to PAI IV536) of Uropathogenic Escherichia coli Strain 536

2002 ◽  
Vol 70 (11) ◽  
pp. 6365-6372 ◽  
Author(s):  
Ulrich Dobrindt ◽  
Gabriele Blum-Oehler ◽  
Gabor Nagy ◽  
György Schneider ◽  
André Johann ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Genetic Structure ◽  
Dna Sequences ◽  
Coli Strain ◽  
Open Reading Frames ◽  
Pathogenicity Islands ◽  
Virulence Determinants ◽  
Core Element ◽  
E Coli ◽  
Virulence Potential

ABSTRACT For the uropathogenic Escherichia coli strain 536 (O6:K15:H31), the DNA sequences of three pathogenicity islands (PAIs) (PAI I536 to PAI III536) and their flanking regions (about 270 kb) were determined to further characterize the virulence potential of this strain. PAI I536 to PAI III536 exhibit features typical of PAIs, such as (i) association with tRNA-encoding genes; (ii) G+C content differing from that of the host genome; (iii) flanking repeat structures; (iv) a mosaic-like structure comprising a multitude of functional, truncated, and nonfunctional putative open reading frames (ORFs) with known or unknown functions; and (v) the presence of many fragments of mobile genetic elements. PAI I536 to PAI III536 range between 68 and 102 kb in size. Although these islands contain several ORFs and known virulence determinants described for PAIs of other extraintestinal pathogenic E. coli (ExPEC) isolates, they also consist of as-yet-unidentified ORFs encoding putative virulence factors. The genetic structure of PAI IV536, which represents the core element of the so-called high-pathogenicity island encoding a siderophore system initially identified in pathogenic yersiniae, was further characterized by sample sequencing. For the first time, multiple PAI sequences (PAI I536 to PAI IV536) in uropathogenic E. coli were studied and their presence in several wild-type E. coli isolates was extensively investigated. The results obtained suggest that these PAIs or at least large fragments thereof are detectable in other pathogenic E. coli isolates. These results support our view that the acquisition of large DNA regions, such as PAIs, by horizontal gene transfer is an important factor for the evolution of bacterial pathogens.

scholarly journals Análise fitoquímica, toxicidade, potencial antioxidante e atividade antibacteriana da Ceiba speciosa (A.St.-Hil.) Ravenna

Revista Fitos ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 9
Author(s):  
Pâmela Milene Dos Santos Braga ◽  
Izabel Bárbara Barcelos ◽  
Richard Da Silva Pereira Calazans ◽  
Alexandra Luiza Silva Bulian ◽  
Josiane Cezar Rodrigues Gabler ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Artemia Salina ◽  
E Coli ◽  
Shigella Spp

O presente estudo realizou a prospecção fitoquímica e avaliou a toxicidade aguda, o potencial antioxidante e a atividade antibacteriana das flores da Ceiba speciosa. A triagem dos metabólitos foi realizada por reações colorimétricas, a toxicidade foi avaliada in vitro por meio do teste de letalidade frente ao microcrustáceo Artemia salina, a atividade antioxidante pelo sequestro de radicais livres, utilizando o radical sintético 2,2-difenil-1-picrilhidrazila (DPPH) e a atividade antimicrobiana pela difusão em disco frente às bactérias Escherichia coli, Shigella spp. e Staphylococcus aureus. Os resultados indicaram a presença de flavonoides e saponinas, observou-se a ausência da toxicidade das amostras (DL50=1.067 ug/mL) e a positividade para a atividade antioxidante (EC50=56,7 mg/mL). Em relação à atividade antibacteriana, as soluções hidrometanólicas a 80% (80:20, v/v) apresentaram efeito nas quatro maiores concentrações (100 mg/mL, 50 mg/mL, 25 mg/mL, 12,5 mg/mL) para as cepas de E. coli e Shiguela spp., e para o S. aureus o mesmo ocorreu a partir de 25 mg/mL. Concluiu-se sobre a ausência de toxicidade, positividade para o efeito antioxidante e atividade antibacteriana para as soluções hidrometanólicas. Sugere-se a continuidade das investigações para exploração do potencial biológico das flores de Ceiba speciosa, que pode constituir-se em uma alternativa como recurso terapêutico.

scholarly journals A nadA Mutation Confers Nicotinic Acid Auxotrophy in Pro-carcinogenic Intestinal Escherichia coli NC101

2021 ◽  
Vol 12 ◽  
Author(s):  
Lacey R. Lopez ◽  
Cassandra J. Barlogio ◽  
Christopher A. Broberg ◽  
Jeremy Wang ◽  
Janelle C. Arthur
Keyword(s):  
Escherichia Coli ◽  
Nicotinic Acid ◽  
De Novo ◽  
Host Cells ◽  
Gene Encoding ◽  
E Coli ◽  
Functional Studies ◽  
Bowel Diseases ◽  
Mechanistic Investigations

Inflammatory bowel diseases (IBDs) and inflammation-associated colorectal cancer (CRC) are linked to blooms of adherent-invasive Escherichia coli (AIEC) in the intestinal microbiota. AIEC are functionally defined by their ability to adhere/invade epithelial cells and survive/replicate within macrophages. Changes in micronutrient availability can alter AIEC physiology and interactions with host cells. Thus, culturing AIEC for mechanistic investigations often involves precise nutrient formulation. We observed that the pro-inflammatory and pro-carcinogenic AIEC strain NC101 failed to grow in minimal media (MM). We hypothesized that NC101 was unable to synthesize a vital micronutrient normally found in the host gut. Through nutrient supplementation studies, we identified that NC101 is a nicotinic acid (NA) auxotroph. NA auxotrophy was not observed in the other non-toxigenic E. coli or AIEC strains we tested. Sequencing revealed NC101 has a missense mutation in nadA, a gene encoding quinolinate synthase A that is important for de novo nicotinamide adenine dinucleotide (NAD) biosynthesis. Correcting the identified nadA point mutation restored NC101 prototrophy without impacting AIEC function, including motility and AIEC-defining survival in macrophages. Our findings, along with the generation of a prototrophic NC101 strain, will greatly enhance the ability to perform in vitro functional studies that are needed for mechanistic investigations on the role of intestinal E. coli in digestive disease.

scholarly journals Isolation and Identification of Infection-Causing Bacteria in Dairy Animals and Determination of Their Antibiogram

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Safia Arbab ◽  
Hanif Ullah ◽  
Weiwei Wang ◽  
Ka Li ◽  
Ali Akbar ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Dairy Farm ◽  
Farm Animals ◽  
Resistant Bacteria ◽  
Salmonella Spp ◽  
Isolation And Identification ◽  
Antibiotic Resistant ◽  
E Coli ◽  
Shigella Spp ◽  
Dairy Animals

Pathogens are always a threat to the livestock and domestic animals due to their exposure to the contaminated environments. The study was conducted to evaluation of the prevalence of Escherichia coli, Shigella spp., Salmonella spp., and S. aureus, in farm animals (cattle and buffalos). A total of 150 (n = 150) samples were collected from cattle and buffaloes, 60 samples from cows’ and buffalo’s teats milk, 30 of water samples, and 60 of fecal samples isolates from dairy farm animals, which may act as reservoir disseminating such pathogens. Farm hygiene, management, and milking procedure were listed through a questionnaire. The most common pathogens detected in this study was E. coli 88 (58%) and S. aureus 81 (54%), followed by Salmonella spp. 32 (21%), and Shigella spp. 44 (29%), respectively. During the antibiogram studies, the results revealed that the highest number of bacterial isolates showed resistance against ampicillin 50 (56.8%), followed by ciprofloxacin 23 (26.1%) and augmentin 22 (25%) of Escherichia coli and ampicillin 49 (60.4%), cefpodoxime 23 (28.3%), and augmentin 20 (24.6%) of S. aureus. In the case of Salmonella spp., the highest resistance was showed by amoxicillin 16 (50%). In Shigella spp., the highest resistance was shown by ampicillin 16 (36.3%), followed by cefpodoxime and ceftazidime 10 (22.7%). The high frequency of isolates in this investigation with multiple antibiotic resistance ranges from 15. MARI % value of S. aureus and E. coli 15 (12.5%), followed by Salmonella and Shigella spp. ranges from 12 (10%), suggesting the presence of various antibiotic-resistant bacteria as well as highly resistant bacteria. The mean ± SD zone areas for the greater resistance are for E. coli and S. aureus, already known to be multiresistant, followed by Salmonella spp. and Shigella spp., when the zone areas are for the low resistance, and the findings determined that there was a little difference between S. aureus and E. coli.

scholarly journals Colibacillosis in a New Zealand white rabbit (Oryctolagus cuniculus)

2017 ◽  
Vol 11 (02) ◽  
pp. 203-206
Author(s):  
Melissa Saravia ◽  
Cristopher Segovia ◽  
Katherinne Valderrama ◽  
Javier Santander
Keyword(s):  
Escherichia Coli ◽  
New Zealand ◽  
Oryctolagus Cuniculus ◽  
Zealand White Rabbit ◽  
Systemic Infection ◽  
16S Sequencing ◽  
E Coli ◽  
Zealand Rabbit ◽  
New Zealand White Rabbit ◽  
Shigella Spp

Colibacillosis is a disease caused by Escherichia coli in a variety of animals, including humans. Rabbit colibacillosis is infrequent or with an incipient description in Chile. Here, we describe an E. coli case in a white New Zealand rabbit at an animal facility in Santiago, Chile. Necropsy, histology, bacteriology, and 16S sequencing indicated an E. coli systemic infection. Phylogenetic analysis suggested that this E. coli J305 isolate is closely related to Shigella spp.

scholarly journals Challenges in identification of enteroinvasive Escherichia coli and Shigella spp. in Lebanon

2020 ◽  
pp. 1-7
Author(s):  
Fatima Bachir Halimeh ◽  
Rayane Rafei ◽  
Seydina Diene ◽  
Mary Mikhael ◽  
Hassan Mallat ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Toxin Production ◽  
Accurate Identification ◽  
E Coli ◽  
Maldi Tof ◽  
Routine Identification ◽  
Shigella Spp ◽  
Identification Technique ◽  
Suitable Marker ◽  
Pcr Targeting

Abstract This study aimed to evaluate the routine identification tools available in Lebanon for differentiation of Escherichia coli and Shigella spp. The identification of 43 isolates defined as Shigella spp. by Api 20E was accessed using MALDI-TOF, serological testing, duplex PCR targeting ipaH (present in Shigella spp. and enteroinvasive E. coli “EIEC”) and lacY (found in E. coli including EIEC but not Shigella spp.) as well as gyrB gene sequencing. Antibiotic susceptibility was investigated as well as Shiga-toxin production. All isolates were identified as E. coli by MALDI-TOF while the PCR showed a disparate group of 26 EIEC, 11 Shigella spp., 5 E. coli and 1 inactive E. coli. However, the sequencing of gyrB gene, which was recently described as a suitable marker for distinguishing E. coli and Shigella spp., identified all isolates as E. coli. Antibiotic resistance was noticeable against ß-lactams, rifampicin, trimethoprim-sulfamethoxazole, gentamicin, and ciprofloxacin. The most common variants of beta-lactamase genes were blaTEM-1, blaCTX-M-15, and blaCTX-M-3. A great discordance between the used methods in identification was revealed herein. An accurate identification technique able to distinguish E. coli from Shigella spp. in routine laboratories is a pressing need in order to select the appropriate treatment and assess the epidemiology of these bacteria.

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