rDNA sequence analyses of Streptococcus dysgalactiae subsp. equisimilis isolates from pigs

Abstract

The nucleotide sequences of 16S and 23S rRNA genes (rDNA) were determined for 11 isolates of Streptococcus dysgalactiae subsp. equisimilis from slaughtered pigs with endocarditis, arthritis or lymphadenitis and strain ATCC 35666, designated as a strain of subspecies equisimilis. The sequences of each of the genes were compared phylogenetically with the corresponding sequences of S. dysgalactiae subsp. dysgalactiae ATCC 43078 T and ATCC 27957, which were also determined in this study. Based on the 16S rDNA analysis, the isolates of S. dysgalactiae subsp. equisimilis were divided into two distinct groups, designated groups 1 and 2. S. dysgalactiae subsp. equisimilis ATCC 35666 was closely related to the group 2 strains. The S. dysgalactiae subsp. dysgalactiae strains seemed to be associated with the group 1 strains, which was not consistent with the conventional subspecific classification of S. dysgalactiae. In contrast, the 23S rDNA analysis distinguished S. dysgalactiae subsp. dysgalactiae strains from subsp. equisimilis strains. This inconsistency between phylogenies based on 16S and 23S rDNA indicates that 23S rDNA is a more rigid marker for determining the phylogenetic relationships and taxonomic position of these organisms than is 16S rDNA.

Invasive infection caused by Streptococcus dysgalactiae subsp. equisimilis: characteristics of strains and clinical features

“…Eleven isolates of SDSE from pigs slaughtered in Japan with endocarditis, arthritis, or lymphadenitis were characterized on the basis of nucleotide sequences of 16S rRNA and 23S rRNA genes [58]. Our colleagues have completed whole-genome analysis of the pig-derived SDSE L1 strain, finding high homology between this L1 strain and human SDSE strains (GGS_124 and RE378; unpublished data).…”

Isolation and characterization of Streptococcus dysgalactiae from diseased Acipenser schrenckii

“…According to enzymatic profiles, these strains were recommended as the subspecies S. dysgalactiae subsp. equisimilis although it needed more proofs (Nomoto et al, 2006;Kawata et al, 2003). Three-fifth and four-fifth healthy sturgeons died after being challenged with the dosage of 4 × 10 8 CFU of sturgeon's isolates and LD50 value of one representative isolate for crucian carps was 2.45 × 10 8 -5.54 × 10 8 CFU even after passage through them three times.…”

Soft tissue infection caused by Streptococcus dysgalactiae subsp. equisimilis possessing group Aantigen: a and review of the literature

“…Three cases of iatrogenic SDSE infection following transfusion of platelet concentrates were described [19], as well as cases of nosocomial infections [30]. It was found that most patients with invasive infections caused by SDSE were suffering from additional disorders, especially with cardiovascular diseases of atherosclerotic etiology, diabetes, obesity, [72,73], dogs [74], camels [75], cattle [44] and sea otters [76]. Marked differences have been found between SDSE strains deriving from humans and animals [44,73].…”

“…It was found that most patients with invasive infections caused by SDSE were suffering from additional disorders, especially with cardiovascular diseases of atherosclerotic etiology, diabetes, obesity, [72,73], dogs [74], camels [75], cattle [44] and sea otters [76]. Marked differences have been found between SDSE strains deriving from humans and animals [44,73]. Kawata et al [73] discovered no streptokinase activity on human plasminogen in any of 11 SDSE strains isolated from pigs, such activity being one of the most important distinctive features of this bacterium [1].…”

“…Marked differences have been found between SDSE strains deriving from humans and animals [44,73]. Kawata et al [73] discovered no streptokinase activity on human plasminogen in any of 11 SDSE strains isolated from pigs, such activity being one of the most important distinctive features of this bacterium [1]. Due to lack of data, it is not yet certain whether animals participate in transmission of that microorganism to people [70].…”