scholarly journals PCR for Detection of Shigella spp. in Mayonnaise

1998 ◽  
Vol 64 (4) ◽  
pp. 1242-1245 ◽  
Author(s):  
Eduardo Villalobo ◽  
Antonio Torres

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.

1989 ◽  
Vol 35 (4) ◽  
pp. 487-491 ◽  
Author(s):  
Paul H. Goodwin

Xylella fastidiosa DNA, partially digested with Sau3A, was ligated into the cosmid vector, pUCD615. Approximately 4500 ampicillin-resistant Escherichia coli colonies were obtained. The frequency of complementation of leucine auxotrophy in transfected E. coli indicated that the cosmid gene bank was representative of X. fastidiosa genomic DNA. Colonies were lysed directly onto nitrocellulose membranes using a thermo-inducible λ lysogen and screened for expression of X. fastidiosa antigens. Approximately 16.5% of a random sample of clones were found to express X. fastidiosa antigens as determined by Western blots. These proteins comigrated with proteins of X. fastidiosa and ranged in molecular weight from 10 000 to 160 000. Conjugation of several of the plasmids into Erwinia stewartii resulted in expression of the similar molecular weight cloned proteins with similar levels of expression as in E. coli.Key words: Xylella fastidiosa, Pierce's disease, immunological clone screening, thermo-inducible lysogeny.


Genetics ◽  
1994 ◽  
Vol 136 (1) ◽  
pp. 17-26
Author(s):  
I Matic ◽  
M Radman ◽  
C Rayssiguier

Abstract To get more insight into the control of homologous recombination between diverged DNA by the Mut proteins of the long-patch mismatch repair system, we have studied interspecies Escherichia coli/Salmonella typhimurium recombination. Knowing that the same recombination pathway (RecABCD) is responsible for intraspecies and interspecies recombination, we have now studied the structure (replacement vs. addition-type or other rearrangement-type recombinants) of 81 interspecies recombinants obtained in conjugational crosses between E. coli donor and mutL, mutS, mutH, mutU or mut+ S. typhimurium recipients. Taking advantage of high interspecies sequence divergence, a physical analysis was performed on one third of the E. coli Hfr genome, which was expected to be transferred to S. typhimurium F- recipients during 40 min before interruption of the mating. Probes specific for each species were hybridized on dot blots of genomic DNA, or on colonies, and the composition of the rrn operons was determined from purified genomic DNA. With very few exceptions, the structure of these interspecies recombinants corresponds to replacements of one continuous block of the recipient genome by the corresponding region of the donor genome.


2005 ◽  
Vol 68 (2) ◽  
pp. 239-245 ◽  
Author(s):  
CESAR I. BIN KINGOMBE ◽  
MARIA-LUCIA CERQUEIRA-CAMPOS ◽  
JEFFREY M. FARBER

A strategy for the detection, identification, and differentiation of enteroinvasive Escherichia coli (EIEC) and Shigella spp. has been developed. The strategy includes (i) a multiplex PCR for the amplification of two virulence genes, i.e., iuc (222 bp) and ipaH (629 bp); (ii) amplification of the ial gene (a 1,038-bp amplicon) located within a large plasmid; and (iii) restriction fragment length polymorphism (RFLP) of the ial gene amplicon. The multiplex PCR provided three patterns. Pattern 1 (iuc−/ipaH+) was found in 10 (67%) of 15 EIEC strains tested, pattern 2 (iuc+/ipaH−) in only 2 (4.4%) of 46 non-EIEC isolates, whereas pattern 3 (iuc+/ipaH+) was observed in all Shigella spp. and also in 5 (33%) of 15 EIEC strains tested. The pattern 3 EIEC strains were all positive for the ial gene. The PCR-RFLP of the ial gene amplicon using the endonuclease AclI was used to differentiate Shigella spp. from the EIEC strains that belonged to pattern 3. The ial gene was present in 21 (38%) of 56 and 6 (40%) of 15 Shigella spp. and EIEC strains tested, respectively. The PCR-RFLP of the ial gene amplicon divided the strains in two types. Type 1 did not contain the restriction enzyme site and was found in 6 (100%) of 6 EIEC strains, 4 (80%) of 5 Shigella boydii, and 4 (100%) of 4 Shigella dysenteriae strains tested. Type 2, which gave two fragments of 286 and 752 bp, was observed in 5 (83%) of 6 Shigella flexneri strains and 6 (100%) of 6 Shigella sonnei strains. Detection, identification, and differentiation of Shigella spp. and EIEC were achieved by analyses of the PCR patterns and RFLP types. To our knowledge, this is the first study to demonstrate a simple and rapid method for detecting, identifying, and differentiating, at the molecular level, Shigella spp. and EIEC strains. This method will have tremendous utility as an epidemiological tool and in helping to develop policies, risk assessments, and national and international methods for Shigella spp.


2013 ◽  
Vol 310 ◽  
pp. 157-161 ◽  
Author(s):  
Jie Xue ◽  
Wen Qiang Wei ◽  
Dong Yan Zhang ◽  
Yong Li Li ◽  
Xin Zhang ◽  
...  

FLO5 has been identified as a dominant flocculation gene. The goal of this study is to clone the FLO5 gene from Saccharomyces cerevisiae and express it in E. coli. In this study, the FLO5 gene amplified by PCR from S. cerevisiae was cloned into prokaryotic expression vector pET-28a to form expression vector pET28a-FLO5, finally, transferred into E.coli BL21. Methods: FLO5 gene was amplified by PCR from genomic DNA extracted from Saccharomyces cerevisiae. The amplified FLO5 gene fragment was then recombined with clone vector pMD18-T to form clone vector pMD18-T-FLO5 amplified in E.coli JM109. After confirmed with sequencing, FLO5 fragment cut out from pMD18-T-FLO5 by enzyme EcoRI and NotI was recombined into expression vector pET-28a to form vector pET28a-FLO5. Vector pET28a-FLO5 was then transferred into E. coli BL21 and protein FLO5 was expressed in E. coli BL21 by the induction with IPTG. Expressed protein fragments separated by SDS-PAGE showed a band with the size of protein FLO5 suggesting the expression of gene FLO5. with the expected This study will lay the foundation for further research in studying flocculating effect of exogenous protein expressed by genetic engineering and making new flocculating agent through recombinant engineering.


2007 ◽  
Vol 189 (17) ◽  
pp. 6482-6486 ◽  
Author(s):  
Anne-Laure Prunier ◽  
Raymond Schuch ◽  
Reinaldo E. Fernández ◽  
Anthony T. Maurelli

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.


Author(s):  
Alina L. NISTOR ◽  
Mihaela MIHAI ◽  
Ancuța M. ROTAR ◽  
Carmen R. POP

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.


2016 ◽  
Vol 18 (2) ◽  
pp. 167
Author(s):  
Dearesty Safirah ◽  
Is Helianti ◽  
Hermin Pancasakti Kusumaningrum ◽  
Anto Budiharjo

The paper industry contributed the environment pollution due to chlor substances. Utilization of alkalothermophilic xylanase enzyme as a biocatalyst in the production of paper may become an environmentally friendly biobleaching alternative. Bacillus halodurans CM1 produces xilanase enzyme that had optimal activity at pH 9 and temperature 70°C. Previous study showed that this CM1 strains has several xilanase genes. The cloning of one of these alkalothermophiic xylanase (alkxyn) gene has been already conducted. This study aimed to clone alkxyn gene that encode alkalothermophilic xylanase enzyme from B. halodurans CM1 into Escherichia coli DH5α. Amplification of alkxyn has been carried out using primers for amplification xylanase 30 kDa. The alkxyn gene fragment was inserted into pGEM-T Easy vector and then transformed into E. coli DH5α. The results showed that the recombinant of E. coli DH5α harboring alkxyn gene from B. halodurans CM1 has been obtained. The sequences analysist based on BLAST showed that alkxyn fragment has homology (99%) with the alkaliphilic xylanase gene from Bacillus sp. 31 which encodes alkaliphilic xilanase (Genebank assession number: JF912895.1). Keywords: cloning, Bacillus halodurans CM1, xylanase, alkalothermophilic.


Author(s):  
Rodolfo Notario ◽  
Noemi Borda ◽  
Telma Gambande ◽  
Emma Sutich

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.


Sign in / Sign up

Export Citation Format

Share Document