Simple and rapid PCR method for identification of streptococcal species relevant to animal infections based on 23S rDNA sequence

Abstract

A PCR identification system targeting 23S rDNA sequences for the identification of eight streptococcal species relevant to animal infections (Streptococcus agalactiae, S. bovis, S. canis, S. dysgalactiae, S. equi, S. porcinus, S. suis and S. uberis) was developed. This system consists of two PCR reactions, A and B, in which seven and eight primers, respectively, are used simultaneously, and was designed so that each amplification product indicates a species by its size. A total of 111 cultures, including the type strain of eight species, could be successfully identified and differentiated as individual species, except for the cross reactivity between S. bovis and S. equinus. The developed PCR system can complete the identification procedure for eight streptococcal species through two tube reactions per isolate, and, therefore, might provide a rapid, simple and accurate diagnostic tool for veterinary laboratories.

Notice of Retraction: In Vitro Antibacterial Activity of Medicinal Herb Extracts against Five Drug-Resistant Streptococcus Suis Strains

“…After thawing, the samples were streaked on Columbia agar plates supplemented with 5% defibrinated sheep blood (BAP) (Biome´rieux, France) and Streptococcus -selective drugs (polymyxin B and nalidixic acid, Sigma, USA) and cultured at 37°C in an atmosphere of 5% CO2 for 24 h.Suspected strains were separated by colonial morphology [16][17][18] and confirmed as Streptococcus suis by biochemical characteristics [19] and a special PCR [20]. Once isolated and identified, the Streptococcus suis isolates were suspended in brain heart infusion broth (Difco, USA) containing 25% glycerol and stored at -80 °C until thawed and subcultured prior to antibacterial activity testing.…”

Identification of 43 Streptococcus Species by Pyrosequencing Analysis of the rnpB Gene

“…Streptococcal species can be identified by measuring the tRNA intergenic lengths (8) and up to 31 species were distinguishable when the fragments were separated by capillary electrophoresis (2). Size separation can also be used for species identification when combined with amplification of selected targets (11,23), arbitrarily primed PCR (33), and restriction of amplified rRNA genes (21,37). The latter can discriminate a large number of species, but in all of these methods the identification is based on complex band patterns with limitations in resolution of closely related species.…”

Bovine Mastitis Caused By Streptococcus uberis: Virulence Factors and Biofilm

“…Phenotypic identification of S. uberis is determined on conventional protocols such as examination of cultural and morphological characteristics, standard biochemical tests, and enzyme activity [29,30]. In order to confirm identification, molecular assays were designed [31][32][33][34]. Correct identification is necessary for an efficient therapeutic choice and for also supervising the mastitis control schemes in the herds.…”