Characterization of class I integrons among Salmonella enterica serovar Enteritidis isolated from humans and poultry

Salmonella isolates were recovered from bulk tank milk as part of the National Animal Health Monitoring System (NAHMS) Dairy 2002 and 2007 surveys. In-line milk filters were also tested in the 2007 survey. The objective of this study was to determine the prevalence of antimicrobial resistance among Salmonella enterica isolates from bulk milk and milk filters in the NAHMS Dairy 2002 and 2007 surveys and to further characterize resistant isolates. Susceptibilities to 15 antibiotics were determined for 176 Salmonella isolates of 26 serotypes using an automated antimicrobial susceptibility system. Resistant isolates were screened by PCR for the presence of the extended-spectrum β-lactamase (blaCMY) gene and class I integrons and further characterized by pulsed-field gel electrophoresis. Thirty isolates (17.0%) representing six S. enterica serotypes exhibited resistance to at least one antimicrobial agent (serotypes Newport [14 of 14 isolates exhibited resistance], Dublin [7 of 7], Typhimurium [3 of 5], Kentucky [4 of 22], Anatum [1 of 13], and Infantis [1 of 2]). Twenty isolates (11.4%), including all 14 Newport, 3 Dublin, 2 Typhimurium, and 1 Infantis isolate, displayed the typical multidrug-resistant, blaCMY-positive (MDR-AmpC) phenotype which included resistance to ampicillin, chloramphenicol, streptomycin, sulfonamide, and tetracycline, plus resistance to amoxicillin–clavulanic acid and extended-spectrum cephalosporins. Five of the MDR-AmpC isolates carried class I integrons (2.8%). Two-enzyme (XbaI and BlnI) pulsed-field gel electrophoresis discerned clades within serotypes and, together with the resistance profiles, identified strains that appeared to have persisted temporally and geographically. These results suggest that there is a low but appreciable risk of infection with MDR Salmonella from consumption of nonpasteurized milk and dairy products.

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Isolation and molecular characterization of Salmonella enterica serovar Enteritidis from poultry house and clinical samples during 2010

Food Microbiology ◽

10.1016/j.fm.2013.08.003 ◽

2014 ◽

Vol 38 ◽

pp. 67-74 ◽

Cited By ~ 39

Author(s):

Ezat H. Mezal ◽

Ashley Sabol ◽

Mariam A. Khan ◽

Nawab Ali ◽

Rossina Stefanova ◽

...

Keyword(s):

Molecular Characterization ◽

Salmonella Enterica ◽

Clinical Samples ◽

Salmonella Enterica Serovar Enteritidis ◽

Poultry House

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Molecular characterization of Salmonella enterica serovar Enteritidis on retail raw poultry in six provinces and two National cities in China

Food Microbiology ◽

10.1016/j.fm.2014.07.012 ◽

2015 ◽

Vol 46 ◽

pp. 74-80 ◽

Cited By ~ 26

Author(s):

Yin Wang ◽

Baowei Yang ◽

Yun Wu ◽

Zengfeng Zhang ◽

Xiaofeng Meng ◽

...

Keyword(s):

Molecular Characterization ◽

Salmonella Enterica ◽

Salmonella Enterica Serovar Enteritidis ◽

Raw Poultry

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Characterization of bacteriophages used in the Salmonella enterica serovar Enteritidis phage-typing scheme

Journal of Medical Microbiology ◽

10.1099/jmm.0.000034-0 ◽

2009 ◽

Vol 58 (1) ◽

pp. 86-93 ◽

Cited By ~ 32

Author(s):

N. De Lappe ◽

G. Doran ◽

J. O'Connor ◽

C. O'Hare ◽

M. Cormican

Keyword(s):

Genome Size ◽

Salmonella Enterica ◽

Pcr Amplification ◽

Initial Step ◽

Phage Typing ◽

Salmonella Enterica Serovar Enteritidis ◽

Banding Patterns ◽

Typing Scheme ◽

Phage Dna

The 16 Salmonella enterica serovar Enteritidis (S. Enteritidis) typing phages (SETPs) used in the Laboratory of Enteric Pathogens (Health Protection Agency, London, UK) phage-typing scheme have not previously been characterized in detail. We have examined the adsorption properties of the phages with respect to a number of S. enterica serovars and defined phage morphology with electron microscopy. PFGE was used to estimate overall genome size and banding patterns generated by electrophoresis following restriction endonuclease digestion of the genome with HindIII were compared. PCR amplification and sequencing of selected genes was performed. The 16 phages comprise three morphotypes, Podoviridae (SETP1, 8, 10, 14, 15 and 16), Siphoviridae (SETP3, 5, 7, 11, 12 and 13) and Myoviridae (SETP2, 4, 6 and 9). All Podoviridae and Siphoviridae, but not Myoviridae, adsorbed to the O12 lipopolysaccharide antigen of Salmonella serogroups B (4,12) and D1 (9,12). The genome sizes for the Podoviridae and Siphoviridae (PFGE-A) were approximately 42 kb. The genome size for Myoviridae SETP2, 4 and 9 was 36.5 kb, and for myovirus SETP6 was 27 kb. HindIII digestion of phage DNA produced 9 distinct patterns of 8 to 11 bands. Relationships between phages based on digest patterns were consistent with those defined by morphology. The Podoviridae had homologues of several P22 genes while the Siphoviridae had homologues of several genes present in the sequenced siphovirus SETP3 (EF177456). This study represents an initial step in characterizing the molecular basis that underlies the widely used S. Enteritidis typing scheme.

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Molecular Characterization of Antimicrobial Resistance in Escherichia coli from Rabbit Farms in Tai’an, China

BioMed Research International ◽

10.1155/2018/8607647 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 4

Author(s):

Xiaonan Zhao ◽

Jie Yang ◽

Zijing Ju ◽

Weishan Chang ◽

Shuhong Sun

Keyword(s):

Escherichia Coli ◽

Gene Cassette ◽

Human Medicine ◽

Class I ◽

E Coli ◽

Faecal Samples ◽

Class I Integrons ◽

Reasonable Use ◽

Sequence Types

To investigate the prevalence and resistance against antimicrobials of Escherichia coli (E. coli) in Tai’an, March 2016, a total of 55 E. coli strains were isolated from 60 faecal samples of diarrheic rabbits collected from three rabbit farms in Tai’an. The E. coli isolates were assayed for antimicrobial susceptibility and prevalence of resistance genes and Class I integrons and genotyped using Multilocus Sequence Typing (MLST). All the E. coli isolates were sensitive to ceftazidime, ceftriaxone, imipenem, and amikacin, while 78.2% of the isolates showed resistance against tetracycline, and 65.5% were resistant against ampicillin. The most common resistance gene detected was blaTEM, present in 98.2% of isolates, followed by blaCTX-M (94.6%) and sul2 (58.2%). Class I integrons were detected in 17 out of the 55 (30.9%) E. coli strains. Seven kinds of gene cassette were detected: dfrA17 + aadA5, dfrA1 + catB3 + aacA4, aadA2 + LinF, dfrA1 + aadA1, aadA22, dfrA12 + orfF + addA2, and aadA16 + dfrA27 + arr-3. All the 55 E. coli strains were identified and classified as 13 sequence types (STs); ST302 (22/55, 40.0%) was the most prevalent type, followed by ST370 (12/55, 21.8%). This study showed that E. coli isolated from diarrheic farmed rabbits in the Tai’an area exhibit sometimes very frequent resistance to antimicrobials important to human medicine, which further highlights the need for reasonable use of antibiotics.

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Characterization of the ELPhiS Prophage from Salmonella enterica Serovar Enteritidis Strain LK5

Applied and Environmental Microbiology ◽

10.1128/aem.07241-11 ◽

2012 ◽

Vol 78 (6) ◽

pp. 1785-1793 ◽

Cited By ~ 17

Author(s):

L. Farris Hanna ◽

T. David Matthews ◽

Elizabeth A. Dinsdale ◽

David Hasty ◽

Robert A. Edwards

Keyword(s):

Salmonella Enterica ◽

Bacterial Pathogens ◽

Genomic Analysis ◽

Bacterial Genomes ◽

Salmonella Enterica Serovar Enteritidis ◽

Content Type ◽

Transfer Genes ◽

Screen Approach ◽

Lysogenic Phage

ABSTRACTPhages are a primary driving force behind the evolution of bacterial pathogens by transferring a variety of virulence genes into their hosts. Similar to other bacterial genomes, theSalmonella entericaserovar Enteritidis LK5 genome contains several regions that are homologous to phages. Although genomic analysis demonstrated the presence of prophages, it was unable to confirm which phage elements within the genome were viable. Genetic markers were used to tag one of the prophages in the genome to allow monitoring of phage induction. Commonly used laboratory strains ofSalmonellawere resistant to phage infection, and therefore a rapid screen was developed to identify susceptible hosts. This approach showed that a genetically tagged prophage, ELPhiS (Enteritidis lysogenic phage S), was capable of infectingSalmonellaserovars that are diverse in host range and virulence and has the potential to laterally transfer genes between these serovars via lysogenic conversion. The rapid screen approach is adaptable to any system with a large collection of isolates and may be used to test the viability of prophages found by sequencing the genomes of various bacterial pathogens.

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