Pulsed-Field Gel Electrophoresis in Differentiation of Erysipelothrix Species Strains

Abstract

We report here the first analysis of Erysipelothrix spp. using pulsed-field gel electrophoresis (PFGE). Seventy strains of Erysipelothrix spp. were analyzed. SmaI, AscI, and NotI were tested for the ability to cleave the DNA extracted from those strains, and among them, SmaI was the most reliable enzyme. Sixty-three distinct PFGE patterns were produced, and no DNA degradation was observed, allowing the identification of all of the strains. Based on these results and on those of a previous analysis using randomly amplified polymorphic DNA and ribotyping, PFGE with SmaI might be considered to be more sensitive than those methods and to be the best method for epidemiological studies of strains of this genus.Erysipelothrix rhusiopathiae is a gram-positive, slender, and straight or slightly curved rod that causes a wide spectrum of diseases in animals, birds, and humans (14,49). This bacterium has been isolated in most parts of the world, not only from sick and healthy animals but even from pork, seafood, retail game meat, and chicken meat (11,19,26,27,38,40,44). Human infections with this bacterium are usually related to occupational exposure (33). However, infection after consumption of undercooked pork and infections of patients with no history of contact with animals or skin lesions have been reported, and in many cases, the source of infection has not been identified (6,13,20,28,37). Moreover, potential errors in the recognition of this organism isolated from human infections due to unusual clinical presentations and the possibility of underdiagnosed infections have been reported (3, 10, 34). PCR-based assays for the rapid diagnosis of Erysipelothrix species have been described (22, 39, 42). However, to proceed with an epidemiological study and identify the source of infection, it is necessary to be able to identify each strain isolated from a case or outbreak, as well as the relatedness among the strains isolated from the possible source.During the last few years, molecular biological methods such as randomly amplified polymorphic DNA (RAPD), ribotyping, and pulsed-field gel electrophoresis (PFGE) have been demonstrated to be reliable tools for the differentiation of species and strains of one genus and for use in epidemiological studies of several pathogenic bacteria (9,15,16,24,32,(46)(47)(48). Although PFGE has been considered to be the "gold standard" among these methods (30), studies have shown that this method can be less sensitive than ribotyping and PCR-based methods with regard to the ability to differentiate between bacterial strains of some species (5,36,45). Moreover, there is no standard and universal PFGE protocol for all species of bacteria and it is necessary to adapt the procedures and choose a suitable enzyme for each genus or species. However, the use of this method for strains of the genus Erysipelothrix has not been reported. Therefore, we describe herein the first analysis of a large collection of Erysipelothrix species strains by PFGE. MATERIALS AND METHODSBacterial strains. Seventy strai...

Clonal Lineages of Erysipelothrix rhusiopathiae Responsible for Acute Swine Erysipelas in Japan Identified by Using Genome-Wide Single-Nucleotide Polymorphism Analysis

“…SmaI is widely used for single-digestion PFGE analyses of E. rhusiopathiae (7,24). The genomic DNA of the Fujisawa and Koganei 65-0.15 strains and 13 E. rhusiopathiae strains that were randomly selected from the clinical strains isolated after 2007 (designated "recent strains" in this article) was digested with SmaI and analyzed by PFGE.…”

Comparison of pulsed-field gel electrophoresis patterns of antimicrobial-resistant Escherichia coli and enterococci isolates from the feces of livestock and livestock farmers in Japan

“…Phenotypic methods that assess phenotypic differences are inherently limited by the capability of microorganisms to alter the expression of the underlying genes and to produce similar antibiotic resistance phenotypes by mutations in different genes (Arbeit, 1995;Martinez and Baquero, 2000). During the last decade, genotypic methods such as randomly amplified polymorphic DNA (RAPD), ribotyping, and pulsed-field gel electrophoresis (PFGE) have been demonstrated to be reliable tools for the differentiation of strains and for use in epidemiological studies of several pathogenic bacteria (Arbeit, 1995;Gori et al, 1996;Louie et al, 1999;Okatani et al, 2001;Tynkkynen et al, 1999). Among these methods, PFGE is currently considered to be the "gold standard" for the differentiation of E. coli and enterococci strains (Louie et al, 1999;Morrison et al, 1999;Swaminathan et al, 2001), and to be used to provide information about the potential clonal dissemination of resistant strains (Hoyle et al, 2005) and the ecology of pathogenic E. coli in a microbial ecosystem (Avery et al, 2004;LeJeune et al, 2004;Wetzel and LeJeune, 2006).…”

Characterization of Erysipelothrix Species Isolates from Clinically Affected Pigs, Environmental Samples, and Vaccine Strains from Six Recent Swine Erysipelas Outbreaks in the United States

“…strain 2 (serotype 18) were analyzed, and Spa proteins can be classified into three molecular species, SpaA, SpaB, and SpaC (29). The SpaA protein was identified in E. rhusiopathiae serotypes 1a, 1b, 2,5,8,9,12,15,16,17, and N, the SpaB protein was identified in E. rhusiopathiae serotypes 4, 6, 11, 19, and 21, and the SpaC protein was identified only in serotype 18 (29). Additional work further differentiated SpaB into subtypes SpaB1 (serotypes 4,6,8,19,21) and SpaB2 (serotype 11) (21).…”

“…have been isolated from domestic and wild species of both birds and mammals and have been identified as the causative agent of the clinical disease known as "erysipelas" in animals and "erysipeloid" in humans (2). The genus Erysipelothrix consists of four species and 25 associated serotypes: E. rhusiopathiae (serotypes 1a, 1b, 2, 4, 5,6,8,9,11,12,15,16,17,19,21, N), E. tonsillarum (serotypes 3,7,10,14,20,22,23), Erysipelothrix sp. strain 1 (serotype 13), and Erysipelothrix sp.…”

“…In addition to improved diagnostic assays, methods to further characterize and differentiate Erysipelothrix spp. through the use of randomly amplified DNA, pulsed-field gel electrophoresis, and ribotyping have been shown to be useful and credible (13)(14)(15)17).…”