Analysis of the prtP gene encoding porphypain, a cysteine proteinase of Porphyromonas gingivalis.

The cloning and sequencing of the gene encoding porphypain, a cysteine proteinase previously isolated from detergent extracts of the Porphyromonas gingivalis W12 cell surface, are described. The prtP gene encoded a unique protein of 1,732 amino acids, including a putative signal sequence for protein secretion. The predicted molecular mass for the mature protein was 186 kDa, which was close to the observed molecular mass of 180 kDa. There was one copy of prtP in the genomes of seven P. gingivalis strains examined. The gene was located 5' to a region with a high degree of homology to the insertion element IS1126 in P. gingivalis W12. The PrtP protein had regions of high homology to HagA, a hemagglutinin of P. gingivalis, and to several purported proteinases of P. gingivalis that have Arg-X specificity. A detailed comparison of genes encoding the latter and cpgR suggested that rgp-1, prpR1, prtR, agp, cpgR, and possibly prtH were derived from identical genetic loci. Although an rgp-1-like locus was detected in seven P. gingivalis strains by Southern blot analyses, agp and cpgR were not detected, not even in the strains from which they were originally isolated. In addition, at least 20 copies of a repeat region common to PrtP, the Rgp-1-like proteins, and HagA were observed in each of the seven genomes examined. The repeat region hybridization patterns for strains W83 and W50 were very similar, and they were identical for strains 381 and ATCC 33277, providing further evidence that these strains are closely related genetically

Sequence analysis of the cloned streptococcal cell surface antigen I/II

AbstractThe gene spa P (formerly designated as spa P1) encoding the Mr 185,000 surface antigen (I/II) of Streptococcus mutons, serotype c (NG5), has been sequenced. The gene (4683 bp) encodes a protein of 1561 amino acid residues including putative signal peptide (residues 1–38) and transmembrane (residues 1537–1556) sequences. The N-terminal region (60–550) has alanine-rich repeats and is predicted to be α-helical. However, the C-ternunal region (800–1540) is proline-rich and favours an extended structure. Except for a short central variable region the sequences appear to be highly conserved for S. mutans serotype c. N-Tenninal sequencing of separated antigen I and antigen II polypeptides suggests that the former represents the N-terminal and the latter the C-terminal portions of the intact antigen

Cellular localization of a Hsp90 homologue in Porphyromonas gingivalis

We previously reported an association between elevated serum antibody titers to the 90-kDa human heat shock protein (Hsp90), periodontal health and colonization by Porphyromonas gingivalis . In this study, we examined the cellular localization of the Hsp90 homologue of P. gingivalis . Cultures of P. gingivalis were heat-stressed (45°C) and examined for localization of the Hsp90 homologue. Heat stress induced a 4–5-fold increase in anti-Hsp90 antibody reactivity over that of the unstressed controls. Western blot analysis revealed two bands (44 and 68 kDa) that reacted with anti-Hsp90 antibodies. The 68-kDa band was heat-inducible, while the 44-kDa band was not. Immunogold staining revealed that the Hsp90 homologue localized principally to the membrane and extracellular vesicles. Subcellular fractionation confirmed that the Hsp90 homologue was primarily membrane-associated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72856/1/j.1574-6968.1999.tb08820.x.pd

Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012

Identification and sequence analysis of a methylase gene in Porphyromonas gingivalis.

A gene from the periodontal organism Porphyromonas gingivalis has been identified as encoding a DNA methylase. The gene, referred to as pgiIM, has been sequenced and found to contain a reading frame of 864 basepairs. The putative amino acid sequence of the encoded methylase was 288 amino acids, and shared 47% and 31% homology with the Streptococcus pneumoniae DpnII and E. coli Dam methylases, respectively. The activity and specificity of the pgi methylase (M.PgiI) was confirmed by cloning the gene into a dam- strain of E. coli (JM110) and performing a restriction analysis on the isolated DNA with enzymes whose activities depended upon the methylation state of the DNA. The data indicated that M.PgiI, like DpnII and Dam, methylated the adenine residue within the sequence 5'-GATC-3'