Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Type III group B streptococci (GBS) can be subdivided into three subtypes, RDP III-1, III-2, and III-3, on the basis of numerical analysis of HindIII restriction endonuclease digestion patterns (HindIII RDP) with their chromosomal DNAs. In the present study, the effect of C5a on opsonophagocytic killing of a representative strain from each RDP type was investigated by using a novel optical method for determining opsonophagocytic killing, and the effect of C5a-ase treatment of C5a on opsonophagocytic killing was also investigated. Pre-stimulation of polymorphonuclear leukocytes (PMNs) with C5a significantly increased opsonophagocytic killing of all three strains. The increase in killing was abolished by pretreating the C5a with GBS that express C5a-ase, a treatment that also destroyed the chemoattractant activity of the C5a. The kinetics of killing of the RDP III-2 strain differed from those of the other two strains. The survival of the RDP III-2 bacteria continued to decline over the entire 60-min incubation of the opsonophagocytic assay when PMNs were prestimulated with C5a or with C5a that had been inactivated with GBS C5a-ase (dC5a). In contrast, killing of the RDP III-1 and III-3 strains almost ceased after 20 or 60 min when PMNs were prestimulated with dC5a or C5a, respectively. A difference in bacterial killing between the III-2 strain and the III-1 and III-3 strains therefore became increasingly apparent with prolonged incubation time. The percentage of bacteria surviving in the extracellular fluid was approximately the same as the percentages of bacteria surviving in both intracellular and extracellular locations when PMNs were prestimulated with either C5a or dC5a. These data imply that the majority of bacterial killing occurred following phagocytosis and suggest that the enhanced killing of GBS following prestimulation of PMNs with C5a resulted from increased ingestion of the bacteria.
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PMID:Role of C5a-ase in group B streptococcal resistance to opsonophagocytic killing. 759 Nov 33

Isolates of group B streptococci (GBS) from neonates with early-onset septicaemia are associated with particular restriction endonuclease digestion patterns (RDP types Ia-3 and III-3) of chromosomal DNA. Opsonophagocytosis of serotype Ia and serotype III GBS isolates was studied by the luminol-enhanced phagocytic chemiluminescence (CL) assay. Pools of serum containing GBS type-specific antibody levels equivalent to or just above levels typically found in sera from mothers of infected infants were used. CL intensities induced by GBS isolates of RDP types Ia-2, Ia-3 and III-3 were lower than those of the other RDP types of the same serotype. Opsonophagocytosis was more efficient with serum containing higher concentrations of type-specific antibodies but for RDP type III-3 strains these differences were much less marked than for other RDP types. CL intensity did not correlate with cell surface charge, hydrophobicity or sialic acid content of GBS. Results demonstrate that certain GBS RDP types are more resistant to opsonophagocytosis and suggest that potentially virulent strains with genetic homogeneity may exist.
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PMID:Opsonisation of group B streptococci and restriction endonuclease digestion patterns of their chromosomal DNA. 845 88

Rapid analysis of microbial communities has proven to be a difficult task. This is due, in part, to both the tremendous diversity of the microbial world and the high complexity of many microbial communities. Several techniques for community analysis have emerged over the past decade, and most take advantage of the molecular phylogeny derived from 16S rRNA comparative sequence analysis. We describe a web-based research tool located at the Ribosomal Database Project web site (http://www.cme.msu.edu/RDP/html/analyses. html) that facilitates microbial community analysis using terminal restriction fragment length polymorphism of 16S ribosomal DNA. The analysis function (designated TAP T-RFLP) permits the user to perform in silico restriction digestions of the entire 16S sequence database and derive terminal restriction fragment sizes, measured in base pairs, from the 5' terminus of the user-specified primer to the 3' terminus of the restriction endonuclease target site. The output can be sorted and viewed either phylogenetically or by size. It is anticipated that the site will guide experimental design as well as provide insight into interpreting results of community analysis with terminal restriction fragment length polymorphisms.
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PMID:Terminal restriction fragment length polymorphism analysis program, a web-based research tool for microbial community analysis. 1091 28