Complete genome sequence of Salmonella bacteriophage SS3e.

A Salmonella lytic bacteriophage, SS3e, was isolated, and its genome was sequenced completely. This phage is able to lyse not only various Salmonella serovars but also Escherichia coli, Shigella sonnei, Enterobacter cloacae, and Serratia marcescens, indicating a broad host specificity. Genomic sequence analysis of SS3e revealed a linear double-stranded DNA sequence of 40,793 bp harboring 58 open reading frames, which is highly similar to Salmonella phages SETP13 and MB78.

Anti-Shiga toxin immunoglobulin G antibodies in healthy South Korean slaughterhouse workers.

Background: Slaughterhouse workers are in direct contact with cattle nearly every day. The purpose of this study was to survey the presence and distribution of anti-Shiga toxin 1 (Stx1) immunoglobulin G (IgG) in slaughterhouse workers, enabling a study of the serologic response to this toxin while working in an area at high-risk of Stx-producing Escherichia coli (STEC) infection.

Methods: One thousand seven hundred and twenty-nine serum samples from healthy slaughterhouse employees were collected and surveyed by indirect enzyme-linked immunosorbent assay (ELISA).

Detection of representative enteropathogenic bacteria, Vibrio spp., pathogenic Escherichia coli, Salmonella spp., Shigella spp., and Yersinia enterocolitica, using a virulence factor gene-based oligonucleotide microarray.

Rapid identification of enteropathogenic bacteria in stool samples is critical for clinical diagnosis and antimicrobial therapy. In this study, we describe the development of an approach that couples multiplex PCR with hybridization to a DNA microarray, to allow the simultaneous detection of the 10 pathogens. The microarray was synthesized with 20-mer oligonucleotide probes that were designed to be specific for virulence-factor genes of each strain.

Genetic characterization of atypical Shigella flexneri isolated in Korea.

Three types of serotypically atypical Shigella flexneri strains were isolated from 2007 to 2008 in patients at the Korea National Institute of Health (NIH). These strains were characterized and compared with serologically typical S.flexneri.

Occurrence and distribution of various genetic structures of class 1 and class 2 integrons in Salmonella enterica isolates from foodborne disease patients in Korea for 16 years.

We have investigated the distribution of integrons among 752 multidrug-resistant Salmonella isolates from human febrile and/or diarrheal patients during 1992-2007 and analyzed their genetic characteristics. Here, we report extensive integron analysis results within human isolates during the last 16 years. The gene or gene cassette(s) in the class 1 integrons found in the isolates were dfrA7, dfrA12-orfF-aadA2, aadA2, bla(PSE1), dfrA1-aadA1, dfrA17-aadA5, bla(OXA1)-aadA1, aadB-aadA1, aadA22, aadA1, and aac6'Ib-bla(OXA1)-aadA2.

In vitro synergism of ciprofloxacin and cefotaxime against nalidixic acid-resistant Salmonella enterica serotypes Paratyphi A and Paratyphi B.

Paratyphoid fever is considered an emerging systemic intracellular infection caused by Salmonella enterica serotypes Paratyphi A, B, and C. We performed in vitro time-kill studies on three clinical isolates of nalidixic acid-resistant Salmonella serotype Paratyphi (NARSP) with different concentrations of ciprofloxacin and cefotaxime to identify combinations of antibiotics with synergistic activity against paratyphoid fever. Furthermore, we identify the frequency of mutations to ciprofloxacin, cefotaxime, and rifampin resistance and also sequenced the gyrA, gyrB, parC, and parE genes to identify the cause of resistance in NARSP.

In vitro efficacy of the combination of ciprofloxacin and cefotaxime against nalidixic acid-resistant Salmonella enterica serotype Typhi.

Typhoid fever is a systemic intracellular infection caused by Salmonellaenterica serotype Typhi. The emergence and spread of nalidixic acid-resistant S. Typhi (NARST) is challenging for clinicians in many countries owing to the lack of suitable treatment options.

Assorted ribotypes of Vibrio vulnificus human and environmental isolates.

We subtyped 117 Vibrio vulnificus isolates from 85 V. vulnificus sepsis patients and 32 environmental samples by performing automated ribotyping for the purpose of molecular epidemiological study. Although there was one indistinguishable ribotype among the four human isolates and one environmental isolate, taken as a whole, the ribotypes were highly diverse regardless of sample sources.

Omics-based analysis of the luxS mutation in a clinical isolate of Escherichia coli O157:H7 in Korea.

The purpose of this study was to investigate the relationship between the global regulatory mechanism known as quorum sensing and expression of virulence factors in Escherichia coli O157:H7. A non-polar luxS deletion was introduced into the chromosome of strain CI03J, a human clinical isolate from South Korea, to create the DeltaluxS mutant strain ML03J. Phenotypic characterization of wild-type and mutant strains demonstrated that ML03J had no obvious growth or metabolic defects on 0.

Genotypic and phenotypic diversity of Salmonella enteritidis isolated from chickens and humans in Korea.

Salmonella Enteritidis is the most common cause of salmonellosis in humans in South Korea. It has been recognized that the principal source of human infection with S. Enteritidis is chickens and their products such as meat and eggs.

Identification of Salmonella enterica subspecies I, Salmonella enterica serovars Typhimurium, Enteritidis and Typhi using multiplex PCR.

This study was designed to develop a multiplex PCR method with five specific primer pairs for the detection of Salmonella spp., Salmonella subspecies I, Salmonella enterica serovars Typhimurium, Typhi and Enteritidis. A multiplex PCR was constructed with five primer pairs for the detection of Salmonella and pathogenic Salmonella serovars, including a specific primer pair for Salmonella Typhi, based on the sequence comparison between genomic DNA sequences of 12 Salmonella strains.

Clustering analysis of Salmonella enterica serovar Typhi isolates in Korea by PFGE, ribotying, and phage typing.

Salmonella enterica serovar Typhi is a Gram-negative bacterium causing the acute febrile disease typhoid fever. In Korea from 2004 to 2006, a total of 51 Salmonella Typhi isolates were identified in stool and blood from healthy carriers and patients with or without overseas travel histories. In this study, antibiogram, pulsed-field gel electrophoresis (PFGE), and automated ribotyping were performed as molecular epidemiological methods with phage typing as a classical subtyping tool of the isolates.

Detection of cytolethal distending toxin and other virulence characteristics of enteropathogenic Escherichia coli isolates from diarrheal patients in Republic of Korea.

Cytolethal distending toxins (CDTs) represent an emerging family of newly described bacterial products that are produced by a number of pathogens. The genes encoding these toxins have been identified as a cluster of three adjacent genes, cdtA, cdtB, and cdtC, plus 5 cdt genetic variants, designated as cdt-I, cdt-II, cdt-III, cdt-IV, and cdt- V, have been identified to date. In this study, a general multiplex PCR system designed to detect Escherichia coli cdts was applied to investigate the presence of cdt genes among isolates.

Asymptomatic healthy slaughterhouse workers in South Korea carrying Shiga toxin-producing Escherichia coli.

A total of 1602 stool samples from healthy employees in a slaughter company were screened by PCR for Shiga toxin (Stx)-producing Escherichia coli (STEC). The PCR product of Stx-encoding genes was detected in 90 (5.6%) of 1602 stool samples.

An additional novel antimicrobial resistance gene cluster in Salmonella genomic island 1 of a Salmonella enterica serovar Typhimurium DT104 human isolate.

The multi-antimicrobial resistance gene cluster and its derivatives have been detected in Salmonella genomic island 1 (SGI1), which has been identified in the Salmonella enterica serovar Typhimurium, phage types DT104, DT12, DT120, and U302, as well as other Salmonella serovars, including Agona, Paratyphi B, Albany, Meleagridis, Newport, Cerro, Derby, Dusseldorf, Infantis, Kiambu, and Emek. We acquired 53 Salmonella Typhimurium DT104 isolates from diarrheal patients in Korea. From these isolates, we identified a novel antimicrobial resistance gene cluster as an additional gene cassette in SGI1 from a multi-antimicrobial resistant isolate.

Surveillance of stool samples for the presence of Enterobacter sakazakii among Korean people.

Purpose: Enterobacter sakazakii (E. sakazakii) infections are an important cause of life-threatening meningitis, septicemia, and necrotizing enterocolitis in infants. Dried infant formula milk is an important vehicle for E.

Enteric bacteria isolated from acute diarrheal patients in the Republic of Korea between the year 2004 and 2006.

In an epidemiological survey of human enterobacterial infections in the Republic of Korea during three years from 2004 to 2006, we isolated 1,784 (6.2%, isolation rate of enteropathogens from stool samples) in 2004, 2,547 (9.5%) in 2005 and 3,506 bacteria (12.

Phage types and pulsed-field gel electrophoresis patterns of Salmonella enterica serovar Enteritidis isolated from humans and chickens.

We analyzed 66 Salmonella Enteritidis isolates in 2002. Thirty isolates were obtained from human patients with diarrhea, and 36 were obtained from chickens. A total of ten phage types (PT) were identified in the human and chicken isolates.

Molecular characterization of regulatory genes associated with biofilm variation in a Staphylococcus aureus strain.

Biofilm formation in association with the intercellular adhesion (icaADBC) gene cluster is a serious problem in nosocomial infections of Staphylococcus aureus. In all 112 S. aureus strains tested, the ica genes were present, and none of these strains formed biofilms.

Multilocus sequence typing analysis of Shigella flexneri isolates collected in Asian countries.

The multilocus sequence typing scheme used previously for phylogenetic analysis of Escherichia coli was applied to 107 clinical isolates of Shigella flexneri. DNA sequencing of 3423 bp throughout seven housekeeping genes identified eight new allele types and ten new sequence types among the isolates. S.

A pulsed-field gel electrophoresis typing scheme for Vibrio parahaemolyticus isolates from fifteen countries.

Vibrio parahaemolyticus is an important foodborne pathogen in Taiwan and many other maritime Asian countries where seafood is frequently consumed. A total of 535 strains of V. parahaemolyticus were recovered mostly (97%) from clinical samples obtained in Taiwan or in 14 other countries.

Molecular differentiation of common promoters in Salmonella class 1 integrons.

The integron is a mobile gene element which harbors antibiotic-resistance gene cassettes capable of site-specific integration. Among the four known types of integrons, the class 1 integron has been associated with multidrug-resistance in pathogenic bacteria. These gene cassettes have been the focus of a series of studies.

Isolation of Salmonella enterica subspecies enterica serovar Paratyphi B dT+, or Salmonella Java, from Indonesia and alteration of the d-tartrate fermentation phenotype by disrupting the ORF STM 3356.

Salmonella enterica subspecies enterica serovar Paratyphi B [O1,4,(5),12 : Hb : 1,2] can cause either an enteric fever (paratyphoid fever) or self-limiting gastroenteritis in humans. The d-tartrate non-fermenting variant S. enterica subsp.