Identification of a novel virulence determinant with serum opacification activity in Streptococcus suis.
نویسندگان
چکیده
Streptococcus suis serotype 2 is a porcine and human pathogen with adhesive and invasive properties. In other streptococci, large surface-associated proteins (>100 kDa) of the MSCRAMM family (microbial surface components recognizing adhesive matrix molecules) are key players in interactions with host tissue. In this study, we identified a novel opacity factor of S. suis (OFS) with structural homology to members of the MSCRAMM family. The N-terminal region of OFS is homologous to the respective regions of fibronectin-binding protein A (FnBA) of Streptococcus dysgalactiae and the serum opacity factor (SOF) of Streptococcus pyogenes. Similar to these two proteins, the N-terminal domain of OFS opacified horse serum. Serum opacification activity was detectable in sodium dodecyl sulfate extracts of wild-type S. suis but not in extracts of isogenic ofs knockout mutants. Heterologous expression of OFS in Lactococcus lactis demonstrated that a high level of expression of OFS is sufficient to provide surface-associated serum opacification activity. Furthermore, serum opacification could be inhibited by an antiserum against recombinant OFS. The C-terminal repetitive sequence elements of OFS differed significantly from the respective repeat regions of FnBA and SOF as well as from the consensus sequence of the fibronectin-binding repeats of MSCRAMMs. Accordingly, fibronectin binding was not detectable in recombinant OFS. To investigate the putative function of OFS in the pathogenesis of invasive S. suis diseases, piglets were experimentally infected with an isogenic mutant strain in which the ofs gene had been knocked out by an in-frame deletion. The mutant was severely attenuated in virulence but not in colonization, demonstrating that OFS represents a novel virulence determinant of S. suis.
منابع مشابه
Identification and characterization of the chromosomal yefM-yoeB toxin-antitoxin system of Streptococcus suis
Toxin-antitoxin (TA) systems are widely prevalent in the genomes of bacteria and archaea. These modules have been identified in Escherichia coli and various other bacteria. However, their presence in the genome of Streptococcus suis, an important zoonotic pathogen, has received little attention. In this study, we describe the identification and characterization of a type II TA system, comprisin...
متن کاملIn vitro Transcriptome Analysis of Two Chinese Isolates of Streptococcus suis Serotype 2
The Streptococcus suis serotype 2 (S. suis 2) isolates 05ZYH33 and 98HAH33 have caused severe human infections in China. Using a strand-specific RNA-seq analysis, we compared the in vitro transcriptomes of these two Chinese isolates with that of a reference strain (P1/7). In the 89K genomic island that is specific to these Chinese isolates, a toxin-antitoxin system showed relatively high levels...
متن کاملThe type II histidine triad protein HtpsC is a novel adhesion with the involvement of Streptococcus suis virulence.
Streptococcal histidine triad proteins HTPs are widely distributed within the Streptococcus genus. Based on the phylogenetic relationship and domain composition, HTPs are classified into type I and type II subfamilies. Previous studies revealed that several pathogenic streptococci contain more than one htp gene. We found that the highly virulent strain of Streptococcus suis 2 (S. suis 2), 05ZYH...
متن کاملIdentification of an inducible bacteriophage in a virulent strain of Streptococcus suis serotype 2.
Streptococcus suis infection is considered to be a major problem in the swine industry worldwide. Most virulent Canadian isolates of S. suis serotype 2 do not produce the known virulence markers for this pathogen. PCR-based subtraction hybridization was adapted to isolate unique DNA sequences which were specific to virulent strains of S. suis isolated in Canada. Analysis of some subtracted DNA ...
متن کاملNovel Streptococcus suis Sequence Type 834 among Humans, Madagascar
Two cases of meningitis caused by Streptococcus suis occurred in Madagascar, 1 in 2015 and 1 in 2016. We report the characterization of the novel sequence type, 834, which carried the mrp+/sly+/epf+ virulence marker and a mutation G→T at position 174, leading to a substitution mutS1 to mutS284.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Infection and immunity
دوره 74 11 شماره
صفحات -
تاریخ انتشار 2006