Expression, genetic localization and phylogenic analysis of NAPlr in piscine Streptococcus dysgalactiae subspecies dysgalactiae isolates and their patterns of adherence

Abstract

Streptococcus dysgalactiae, the long recognized mammalian pathogen, has currently received a major concern regarding fish bacterial infection. Adhesion to host epithelial cells and the presence of wall-associated plasminogen binding proteins are prerequisites to Streptococcus infection. This is the first study of the occurrence of nephritis-associated plasminogen-binding receptor (NAPlr) and α-enolase genes in piscine S. dysgalactiae subspecies dysgalactiae (SDSD) isolates. Further characterization of surface localized NAPlr of fish SDSD revealed a similar immune-reactive band of 43 KDa as that from porcine S. dysgalactiae subsp. equisimilis (SDSE). The phylogenetic analysis revealed that NAPlr of fish SDSD is more associated with those of mammalian SDSE and Streptococcus pyogenes rather than of other streptococci. Our findings warrant public attention to the possible implication of these virulence genes in dissemination of SDSD to different tissues of infected hosts and to get advantage to new niches. The SDSD adherence patterns were also studied to better understand their pathogenicity. The patterns of adherence of SDSD on two different cell lines showed a different pattern of adherence. Such difference gives an insight about the variance in host susceptibility to infection.

Biofilm production and other virulence factors in Streptococcus spp. isolated from clinical cases of bovine mastitis in Poland

“…The last group submitted to analysis consisted of isolates of S. dysgalactiae ( n = 41). In this group, only two genes, eno and napr , were selected for the tests, mainly because there is very little knowledge about the mechanisms of invasiveness in this species [ 17 ] Regarding our isolates, the presence of these two genes was confirmed in 76% and 86% of strains, respectively [Table 4 ].…”

Streptococcus dysgalactiae subsp. equisimilis Isolated From Infections in Dogs and Humans: Are Current Subspecies Identification Criteria accurate?

“…Therefore, animal infections are being assigned to SDSD strains, whereas human infections are being assigned to SDSE. Despite the fact that the etiological factor of the majority of human infections reported in literature is SDSE [ 17 , 21 ] and of animal infections—SDSD [ 1 , 10 , 18 ], some cases contradicting this rule were reported, e.g., human infections caused by SDSD [ 14 ] and animal infections caused by SDSE [ 15 ].…”

Isolation, identification and character analysis of Streptococcus dysgalactiae from Megalobrama terminalis

“…dysgalactiae . Prior to this study, S. dysgalactiae infections were reported mainly in marine fish, such as amberjack, mullet and cobia (Abdelsalam, Fujino, Eissa, Chen, & Warda, ). The current study was the first to isolate and describe S. dysgalactiae from a subtropical freshwater fish species, M. terminalis .…”

“…dysgalactiae and β‐haemolytic human S. dysgalactiae subsp. equisimilis (Abdelsalam et al, ; Vandamme, Pot, Falsen, & Devriese, ). To date, all reported strains of S. dysgalactiae isolated from cultured fish are α‐haemolytic S. dysgalactiae subsp.…”