14 research outputs found
image_2_The Surface-Exposed Protein SntA Contributes to Complement Evasion in Zoonotic Streptococcus suis.jpeg
<p>Streptococcus suis is an emerging zoonotic pathogen causing streptococcal toxic shock like syndrome (STSLS), meningitis, septicemia, and even sudden death in human and pigs. Serious septicemia indicates this bacterium can evade the host complement surveillance. In our previous study, a functionally unknown protein SntA of S. suis has been identified as a heme-binding protein, and contributes to virulence in pigs. SntA can interact with the host antioxidant protein AOP2 and consequently inhibit its antioxidant activity. In the present study, SntA is identified as a cell wall anchored protein that functions as an important player in S. suis complement evasion. The C3 deposition and membrane attack complex (MAC) formation on the surface of sntA-deleted mutant strain ΔsntA are demonstrated to be significantly higher than the parental strain SC-19 and the complementary strain CΔsntA. The abilities of anti-phagocytosis, survival in blood, and in vivo colonization of ΔsntA are obviously reduced. SntA can interact with C1q and inhibit hemolytic activity via the classical pathway. Complement activation assays reveal that SntA can also directly activate classical and lectin pathways, resulting in complement consumption. These two complement evasion strategies may be crucial for the pathogenesis of this zoonotic pathogen. Concerning that SntA is a bifunctional 2′,3′-cyclic nucleotide 2′-phosphodiesterase/3′-nucleotidase in many species of Gram-positive bacteria, these complement evasion strategies may have common biological significance.</p
image_3_The Surface-Exposed Protein SntA Contributes to Complement Evasion in Zoonotic Streptococcus suis.jpeg
<p>Streptococcus suis is an emerging zoonotic pathogen causing streptococcal toxic shock like syndrome (STSLS), meningitis, septicemia, and even sudden death in human and pigs. Serious septicemia indicates this bacterium can evade the host complement surveillance. In our previous study, a functionally unknown protein SntA of S. suis has been identified as a heme-binding protein, and contributes to virulence in pigs. SntA can interact with the host antioxidant protein AOP2 and consequently inhibit its antioxidant activity. In the present study, SntA is identified as a cell wall anchored protein that functions as an important player in S. suis complement evasion. The C3 deposition and membrane attack complex (MAC) formation on the surface of sntA-deleted mutant strain ΔsntA are demonstrated to be significantly higher than the parental strain SC-19 and the complementary strain CΔsntA. The abilities of anti-phagocytosis, survival in blood, and in vivo colonization of ΔsntA are obviously reduced. SntA can interact with C1q and inhibit hemolytic activity via the classical pathway. Complement activation assays reveal that SntA can also directly activate classical and lectin pathways, resulting in complement consumption. These two complement evasion strategies may be crucial for the pathogenesis of this zoonotic pathogen. Concerning that SntA is a bifunctional 2′,3′-cyclic nucleotide 2′-phosphodiesterase/3′-nucleotidase in many species of Gram-positive bacteria, these complement evasion strategies may have common biological significance.</p
image_1_The Surface-Exposed Protein SntA Contributes to Complement Evasion in Zoonotic Streptococcus suis.jpeg
<p>Streptococcus suis is an emerging zoonotic pathogen causing streptococcal toxic shock like syndrome (STSLS), meningitis, septicemia, and even sudden death in human and pigs. Serious septicemia indicates this bacterium can evade the host complement surveillance. In our previous study, a functionally unknown protein SntA of S. suis has been identified as a heme-binding protein, and contributes to virulence in pigs. SntA can interact with the host antioxidant protein AOP2 and consequently inhibit its antioxidant activity. In the present study, SntA is identified as a cell wall anchored protein that functions as an important player in S. suis complement evasion. The C3 deposition and membrane attack complex (MAC) formation on the surface of sntA-deleted mutant strain ΔsntA are demonstrated to be significantly higher than the parental strain SC-19 and the complementary strain CΔsntA. The abilities of anti-phagocytosis, survival in blood, and in vivo colonization of ΔsntA are obviously reduced. SntA can interact with C1q and inhibit hemolytic activity via the classical pathway. Complement activation assays reveal that SntA can also directly activate classical and lectin pathways, resulting in complement consumption. These two complement evasion strategies may be crucial for the pathogenesis of this zoonotic pathogen. Concerning that SntA is a bifunctional 2′,3′-cyclic nucleotide 2′-phosphodiesterase/3′-nucleotidase in many species of Gram-positive bacteria, these complement evasion strategies may have common biological significance.</p
Populations (in millions) and percentage distribution by demographic characteristics in the surveillance sites, compared with two reference populations Zhejiang province and China, 2012.
<p>Populations (in millions) and percentage distribution by demographic characteristics in the surveillance sites, compared with two reference populations Zhejiang province and China, 2012.</p
Geographical distribution of the 30 surveillance sites in Zhejiang province, China.
<p>Geographical distribution of the 30 surveillance sites in Zhejiang province, China.</p
Characteristics of urban and rural residence (in millions) in Zhejiang, China, 2012.
<p>Characteristics of urban and rural residence (in millions) in Zhejiang, China, 2012.</p
Crude and standardized<sup>†</sup> incidence (/100,000/year), mortality (/100,000/year) and case-fatality rates (%) of acute cardiovascular diseases by gender, residence and age groups in Zhejiang, China, 2012.
<p>Crude and standardized<sup><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165647#t003fn003" target="_blank">†</a></sup> incidence (/100,000/year), mortality (/100,000/year) and case-fatality rates (%) of acute cardiovascular diseases by gender, residence and age groups in Zhejiang, China, 2012.</p
Flowchart of the Internet-based Comprehensive Chronic Disease Surveillance System (ICDSS) in Zhejiang, China.
<p>Flowchart of the Internet-based Comprehensive Chronic Disease Surveillance System (ICDSS) in Zhejiang, China.</p
Difference in urban and rural residence in crude incidence (/100,000/year), mortality (/100,000/year) and case-fatality rates (%) by age, gender for acute cardiovascular disease subtypes in Zhejiang, China, 2012.
<p>Difference in urban and rural residence in crude incidence (/100,000/year), mortality (/100,000/year) and case-fatality rates (%) by age, gender for acute cardiovascular disease subtypes in Zhejiang, China, 2012.</p
Phase-mode transformation matrix application for transmission line and electromagnetic transient analyses
<p>Demographic, socioeconomic and disease characteristics of patients recruited in the panel.</p