Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0036690 (
sepsis
)
59,461
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The Staphylococcus aureus cell surface protein clumping factor A (ClfA) and the enzyme
sortase A
(SrtA), which attach surface proteins to the cell wall, have both been shown to be virulence factors in models of septic arthritis and
sepsis
. The mRNA levels of clfA, srtA and the putative housekeeping gene gyrase B (gyrB) in S. aureus were determined using real-time PCR during the course of
sepsis
/septic arthritis. Expression was measured in joints, being a target of localized infection, and in kidneys, representing a systemic compartment. In infected kidneys, the mRNA levels of clfA, srtA and gyrB were all decreasing over time, from day 3 of infection to day 14. The transcript numbers of clfA and srtA decreased faster in septic mice than in mice with a non-septic disease. The mRNA levels of clfA and gyrB in joints, though, were increasing during the course of infection. These differences suggest that the specific tissue environment is decisive for the differentiation of staphylococci. Also, there was a negative relationship between bacterial load in a tissue and the numbers of clfA, srtA and gyrB transcripts per colony-forming unit. Possibly enters the majority of bacteria a metabolically dormant steady state at high bacterial loads.
...
PMID:In vivo sortase A and clumping factor A mRNA expression during Staphylococcus aureus infection. 1789 45
Pili are putative virulence factors and promising vaccine candidates in Streptococcus agalactiae (group B Streptococcus [GBS]) infection, a leading cause of neonatal
sepsis
and meningitis. The genes necessary for pilus synthesis and assembly are clustered in pilus islands (PI). Each gene encodes three structural subunits (a backbone and two ancillary proteins) bearing a C-terminal LPXTG motif and two subfamily C sortases (SrtC) involved in covalent polymerization of the subunits. GBS strains also possess the conserved "housekeeping"
sortase A
(SrtA), but its role in pilus assembly is unclear. To address this issue, pilus expression and cell wall anchoring were analyzed in srtA deletion mutants. Loss of SrtA did not affect pilus polymerization. However, pilus expression on the cell surface was reduced, and pili accumulated in the culture supernatant. Furthermore, cell-associated pili could be readily released by detergent treatment, indicating that SrtA is involved in covalent anchoring of pili to the cell wall. When each of the genes comprising PI-2a was systematically deleted, only the absence of ancillary subunit GBS150 or the SrtC required for incorporation of GBS150 into pili mimicked the srtA mutant phenotype. Thus, from these data a model for GBS pilus assembly can be proposed in which PI sortases are responsible for polymerization of the pilus structure, while SrtA is required to covalently attach it to the cell wall, utilizing ancillary pilus subunit GBS150 as the anchor protein.
...
PMID:Sortase A utilizes an ancillary protein anchor for efficient cell wall anchoring of pili in Streptococcus agalactiae. 1854 57
Streptococcus suis serotype 2 is a zoonotic Gram-positive bacterium responsible for arthritis, meningitis, pneumonia and
septicemia
in swine and humans. Little information about the regulation of iron on its gene expression had been reported. In this study, 63 S. suis genes upregulated under an iron-restricted condition were identified using selective capture of transcribed sequences (SCUTS) technique: 23 genes involved in metabolism, 22 genes responsible for the replication and genetic information proceeding of the bacteria, eight genes relative to the construction of the cell wall, five ATP-binding cassette transporters, four transcriptional regulators and one uncharacterized gene conserved among streptococcal species. To adapt to the stress, S. suis modulated its physiological activities, which were validated by the upregulation of RelA (a crucial enzyme in stringent response), ArcA (a component of the arginine deiminase system catalyzing the conversion of arginine to ornithine) and CpdB (a cell surface protein that is a substrate of
sortase A
). All of them were reported to be virulence factors in S. suis or other bacteria. Besides, together with the results of quantitative reverse transcriptase PCR, we found that several homologous genes (fur, fhuGBDA operons) associated with iron uptake as reported in other bacteria were also upregulated under an iron-restricted condition in S. suis.
...
PMID:Identification of Streptococcus suis genes preferentially expressed under iron starvation by selective capture of transcribed sequences. 1919 74
Protein-based vaccines are considered to be the next-generation of pneumococcal vaccines. Here we evaluated the protection elicited by immunization with recombinant glutamyl tRNA synthetase (Gts), polyamine transport protein D (PotD) and
sortase A
(SrtA) antigens in preclinical mouse models. In mucosal immunization studies, intranasal immunization with either Gts, PotD or SrtA could significantly reduce pneumococcal nasopharyngeal and lung colonization and significantly increase mice survival times following invasive pneumococcal challenge, and combinations of these antigens could enhance this protection. In systemic immunization studies, intraperitoneal immunization with multiple protein antigens also provided better protection against pneumococcal
sepsis
caused by different pneumococcal strains. Finally, passive immunization studies showed an additive effect by using multiple anti-sera when compared to single anti-sera. Therefore, a multicomponent protein-based pneumococcal vaccine composed of Gts, PotD or SrtA could confer protection against pneumococcal colonization as well as invasive infections in terms of efficacy of protection and serotype coverage.
...
PMID:Protection against pneumococcal infection elicited by immunization with glutamyl tRNA synthetase, polyamine transport protein D and sortase A. 2246 66