Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0031099 (periodontitis)
 12,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Our recent work has developed specific assays for bacterial dipeptidyl peptidase (DPP) and trypsin-like proteases and we have found them in gingival crevicular fluid (GCF). The purpose of this study was to determine whether their levels reduce following periodontal treatment of chronic periodontitis patients. The probing depth, probing attachment level, gingival index, gingival bleeding index and plaque index were measured at mesio-buccal sites of molars and premolars in 25 untreated patients. At a second visit GCF was collected on filter paper strips for 30 seconds. GCF volumes were determined with a Periotron and the samples eluted into buffer. The patients than received oral hygiene instruction, supra- and subgingival scaling and other appropriate non-surgical treatment. Four weeks later GCF was collected from the same 16 sites and the clinical parameters were measured again. DPP-like activity was determined fluorometrically with Ala-Pro-AFC at pH 8.0 with and without heating to 60 degrees C for 30 minutes. The heat sensitive portion was taken as bacterial DPP activity. Bacterial trypsin-like protease activity was assayed with Z-Val-Lys-Lys-Arg-AFC at pH 7.0 with 2 mM dithiothreitol and 10 microM Z-Phe-Ala-CH2. Following treatment there were marked reductions in clinical parameters, enzyme total activities and concentrations. All reductions were statistically significant at patient and site level using either individual patient or pooled patient data. Bacterial proteases appear to reflect the clinical status and may be of value in monitoring chronic inflammatory periodontal disease.
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PMID:Bacterial proteases in gingival crevicular fluid before and after periodontal treatment. 789 45

To elucidate the mechanism of production of an inflammatory exudate, gingival crevicular fluid (GCF), from periodontal pockets in periodontitis, we examined the vascular permeability enhancement (VPE) activity induced by an arginine-specific cysteine proteinase, Arg-gingipain-1 (RGP-1), produced by a major periopathogenic bacterium, Porphyromonas gingivalis. Intradermal injections into guinea pigs of RGP-1 (> 10(-8) M), or human plasma incubated with RGP-1 (> 10(-9) M), induced VPE in a dose- and activity-dependent manner but with different time courses for the two routes of production. VPE activity induced by RGP-1 was augmented by kininase inhibitors, inhibited by a kallikrein inhibitor and unaffected by an antihistamine drug. The VPE activity in human plasma incubated with RGP-1 also correlated closely with generation of bradykinin (BK). RGP-1 induced 30-40% less VPE activity in Hageman factor-deficient plasma and no VPE in plasma deficient in either prekallikrein (PK) or high molecular weight kininogen (HMWK). After incubation with RGP-1, plasma deficient in PK or HMWK, reconstituted with each missing protein, caused VPE, as did a mixture of purified PK and HMWK, but RGP-1 induced no VPE from HMWK. The VPE of extracts of clinically isolated P. gingivalis were reduced to about 10% by anti-RGP-1-IgG, leupeptin, or tosyl-L-lysine chloromethyl ketone, which paralleled effects observed with RGP-1. These results indicate that RGP-1 is the major VPE factor of P. gingivalis, inducing this activity through PK activation and subsequent BK release, resulting in GCF production at sites of periodontitis caused by infection with this organism.
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PMID:Pathogenesis of periodontitis: a major arginine-specific cysteine proteinase from Porphyromonas gingivalis induces vascular permeability enhancement through activation of the kallikrein/kinin pathway. 804 Feb 77

In the face of an apparently competent immune response to Porphyromonas gingivalis, it is unclear how P. gingivalis evades the immune response and persists in human periodontitis. Particularly germane may be its ability to resist phagocytosis by degrading and not binding serum opsonins. In our study, the resistance by invasive (W83 and A7436) and noninvasive (ATCC 33277) P. gingivalis strains to phagocytosis by human neutrophils was compared with their C3- and IgG-proteolytic activity. The ability of opsonic human serum antibody to inhibit C3 proteolysis was also evaluated. Our results indicate that the more phagocytosis-resistant invasive strains accumulate less 125I-C3 than the noninvasive strain; moreover, invasive strains degrade complement C3 in a dose-dependent manner, inhibitable by rabbit antiserum or adult periodontitis serum. Opsonization and C3 accumulation on strain A7436 were both facilitated by pretreatment with rabbit antiserum, certain adult periodontitis sera, protease inhibitors (p-chloromercuriphenylsulfonic acid, N alpha-p-tosyl-L-lysine chloromethyl ketone, diisopropylfluorophosphate), heat (60 degrees C, 15 min), and were Mg2+ dependent. The sera from 13 human subjects with or without periodontitis were assayed for antibody titers to P. gingivalis (ELISA units), opsonic activity (% of PMN engaged in phagocytosis) and enhancement of C3 accumulation. Statistically significant associations were observed between % of PMN engaged in phagocytosis and % C3 accumulation, between % of PMN engaged in phagocytosis and ELISA units and between % C3 accumulation and ELISA units. Degradation of purified rabbit IgG, but not specific antibody-containing rabbit IgG by P. gingivalis A7436 was observed, and was inhibited by diisopropyl fluorophosphate (DFP) or cold (2 degrees C). Our data suggest that C3 and IgG cleavage by P. gingivalis proteases are inhibitable by antibody and are contributory factors in, but are not the sole determinants of, phagocytosis resistance.
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PMID:Inhibition of C3 and IgG proteolysis enhances phagocytosis of Porphyromonas gingivalis. 825 6

We isolated an enzyme from a major periodontal pathogen, Porphyromonas gingivalis (also called Bacteroides gingivalis), that is capable of initially increasing the coagulant activity of high molecular weight kininogen (HK), releasing bradykinin from HK and low molecular weight kininogen (LK), and destroying the light chain (coagulant portion) of HK. This enzyme, a membrane-bound thiol proteinase that preferentially cleaves the P1-Lys position of tripeptide substrates, is also able to rapidly render fibrinogen nonclottable. We will refer to this enzyme as lys-gingivain because of its origin from P. gingivalis, its classification as a thiol proteinase, and its action as a lysyl-amidase. The activity of lys-gingivain is enhanced by beta-mercaptoethanol, and the enzyme has a molecular mass of 68-70 kDa, a pH optimum of 7.4, and is not inactivated by plasma protease inhibitors. The second-order rate constant for the destruction of the coagulant activity of the HK light chain (surface-binding domain) at 23 degrees C is 2.3 x 10(7) M-1 s-1, and, for cleavages that render fibrinogen unclottable, is 2.05 x 10(6) M-1 s-1. These data suggest that lys-gingivain is a very potent proteinase that would be fully functional in anaerobic periodontal crevices and might participate in the pathogenesis of periodontitis. Lys-gingivain appears to be the most potent kininogenase and fibrase to be described to date.
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PMID:Purification and characterization of a potent 70-kDa thiol lysyl-proteinase (Lys-gingivain) from Porphyromonas gingivalis that cleaves kininogens and fibrinogen. 838 28

The anaerobic bacterium Porphyromonas gingivalis has been implicated as a primary causative agent in adult periodontitis. Several proteinases are produced by this bacterium, and it is suggested that they contribute to virulence and to local tissue injury resulting from infection by P. gingivalis. Cysteine proteinases with specificities to cleave either Arg-X or Lys-X peptide bonds (i.e., gingipains) have been characterized as predominant enzymes associated with vesicles shed from the surface of this bacterium. It has recently been demonstrated that these proteinases are capable of degrading the blood complement component C5, resulting in the generation of biologically active C5a. By using an affinity-purified rabbit antibody raised against residues 9 to 29 of the C5a receptor (C5aR; CD88), we demonstrate that noncysteinyl proteinases associated with vesicles obtained from P. gingivalis cleave the C5aR on human neutrophils. Proteolytic attack of the C5aR by enzymes from the P. gingivalis vesicles was inhibited by TPCK (tolylsullonyl phenylalanyl chloromethyl ketone), PMSF (phenylmethylsulfonyl fluoride), and dichloroisocoumarin, suggesting that serine proteinases are primarily responsible for this degradative activity. The purified vesicle proteinase Lys-gingipain but not Arg-gingipain also cleaved the N-terminal region of the C5aR on the human neutrophils. Lys-gingipain activity was essentially resistant to these inhibitors but was inhibited by TLCK (Nalpha-p-tosyl-L-lysine chloromethyl ketone) and iodoacetamide. A synthetic peptide that mimics the N-terminal region of C5aR (residues 9 to 29; PDYGHY DDKDTLDLNTPVDKT) was readily cleaved by chymotrypsin but not by trypsin, despite the presence of two potential trypsin (i.e., lysyl-X) cleavage sites. The specific sites of cleavage in the C5aR 9-29 peptide were determined by mass spectroscopy for both chymotrypsin and Lys-gingipain digests. This analysis demonstrated that the C5aR peptide is susceptible to cleavage at both potential Lys-gingipain sites (i.e., between residues 17 and 18 [K-D] and 28 and 29 [K-T]) and at two chymotrypsin sites (between residues 14 and 15 [Y-D] and 20 and 21 [L-D]), respectively. These studies suggest that P. gingivalis contains at least two enzymes capable of cleaving the C5aR, Lys-gingipain and a second nontryptic serine proteinase that is distinct from either Arg- or Lys-gingipain.
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PMID:Proteolytic inactivation of the leukocyte C5a receptor by proteinases derived from Porphyromonas gingivalis. 867 97

Gingival crevicular fluid (GCF) contains several different proteinase activities and the study sought to clarify their sources. Gingival tissue and GCF were collected from chronic periodontitis patients. Gel-filtration chromatography of crude tissue extracts yielded cathepsin B and tryptase fractions sensitive to cysteine and serine proteinase inhibitors, respectively. Cell sonicates of suspected periodontal pathogens were prepared from broth cultures of reference strains. Of these, Porphyromonas gingivalis showed much the strongest activity and this had an effector response consistent with the metal-dependent cysteine proteinase described by others. Banding patterns in GCF, tissue and bacterial samples were compared on substrate-impregnated overlay membranes applied to isoelectric focusing gels. On Z-Val-Lys-Lys-Arg-AFC overlays, GCF had bands corresponding to tissue cathepsin B and the enzyme from P. gingivalis, though a contribution from Treponema denticola could not be ruled out. Use of D-Val-Leu-Arg-AFC overlays showed GCF activity similar to tissue tryptase. In GCF there were additional bands that did not correspond to any tissue or bacterial samples and on Z-Ala-Ala-Lys-AFC overlays these closely resembled activity in parotid saliva. The results confirmed that GCF contains tissue cathepsin B and tryptase, while the apparent presence of enzymes from P. gingivalis and possibly T. denticola is consistent with previous reports linking activity to these organisms. The saliva bands demonstrated that contamination of GCF may occur despite rigorous collection procedures.
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PMID:A comparison of cysteine and serine proteinases in human gingival crevicular fluid with tissue, saliva and bacterial enzymes by analytical isoelectric focusing. 880 1

Dipeptidyl peptidase (DPP) II and IV activities were demonstrated in unfixed cryostat sections of gingival tissue from chronic periodontitis patients using histochemistry with 2-methoxy-4-naphthylamine (MNA) substrates. In the case of DPP IV, enzyme localization was confirmed by immunocytochemistry with mouse monoclonal antihuman DPP IV (CD26) antibody. Inflammatory cells containing enzyme were identified in adjacent sections with mouse monoclonal antibodies directed against leukocyte differentiation antigens. Lys-Ala-MNA and Ala-Pro-MNA staining in acid buffer for DPP II was only found in a few fibroblasts in superficial tissue. Staining with Gly-Pro-MNA and Ala-Pro-MNA in alkaline buffer for DPP IV was localized in some CD4 and CD8 positive T lymphocytes, CD68 positive macrophages, and fibroblasts and these cells also reacted with the enzyme antibody. DPP IV-containing macrophages and T lymphocytes were seen in the epithelium. In deeper granulomatous tissue Gram positive and negative bacteria stained with the histochemical substrates, but not the DPP IV antibody. Fibroblast DPP II and IV might participate in cellular interactions with collagen, while T lymphocyte DPP IV may be involved in cell signalling.
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PMID:Histochemical and immunocytochemical localization of dipeptidyl peptidases II and IV in human gingiva. 888 40

Porphyromonas gingivalis contains exceedingly high concentrations of cysteine proteinases with trypsin-like activity which have been implicated as virulence factors in adult-onset periodontitis. These enzymes, referred to as gingipains, cleave protein and peptide substrates after arginine (gingipain R) and lysine residues (gingipain K), and it has been found that neither is easily inhibited by host proteinase inhibitors. Examination of the properties of each proteinase clearly indicates a role(s) for both in the dysregulation of a number of normally tightly controlled pathways. The effects of such uncontrolled proteolysis are the development of edema (kallikrein/kinin pathway activation by gingipain R), neutrophil infiltration (complement pathway activation by gingipain R), and bleeding (degradation of fibrinogen by gingipain K). Since three of the major hallmarks of periodontitis involve increased crevicular flow, neutrophil accumulation at infected sites and bleeding on probing, it seems likely that both P. gingivalis-derived proteinases are important virulence factors in the development of periodontal disease.
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PMID:Porphyromonas gingivalis proteinases as virulence factors in the development of periodontitis. 908 21

Porphyromonas gingivalis is closely associated with the development of some forms of periodontitis. The major cysteine proteinases released by this bacterium hydrolyze peptide bonds only after arginyl (gingipain R) or lysyl residues (gingipain K). No target protein inhibitors have been identified for either enzyme, leading us to investigate their inhibition by human plasma alpha 2-macroglobulin (alpha 2M). Both 50- and 95 kDa gingipain R were efficiently inhibited by alpha 2M, whereas the catalytic activity of gingipain K could not be eliminated. All 3 enzymes were, however, inhibited by a homologous macroglobulin from rat plasma, alpha 1-inhibitor-3 (alpha 1I3). alpha-Macroglobulins must be cleaved in the so-called "bait region" in order to inhibit proteinases by a mechanism involving physical entrapment of the enzyme. A comparison of the amino acid sequences of the 2 macroglobulins indicates that the lack of lysyl residues within the bait region of alpha 2M protects Lys-specific proteinases from being trapped. On this basis, other highly specific proteinases might also not be inhibited by alpha 2M, possibly explaining the inability of the inhibitor to control proteolytic activity in some bacterially induced inflammatory states, despite its abundance (2-5 mg/ml) in vascular fluids.
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PMID:The potential role of alpha 2-macroglobulin in the control of cysteine proteinases (gingipains) from Porphyromonas gingivalis. 908 44

Porphyromonas gingivalis has been associated with the development of adult periodontitis and cysteine proteinases with trypsin-like specificity have been implicated as major virulence factors. We have extracted the major cell-associated trypsin-like proteolytic activity of P. gingivalis W50 using mild sonication. Anion-exchange and gel-filtration FPLC of the sonicate revealed that Arg- and Lys-specific proteinase activity was associated with a 300 kDa complex which could be dissociated into seven bands (48, 45, 44, 39, 27, 17 and 15 kDa) by SDS-PAGE with the 44 kDa band containing two different proteins as shown by N-terminal sequence analysis. On further chromatography of the 300 kDa complex on Arg-Sepharose the majority of the complex eluted from the affinity column as an undissociated complex. However, a small amount dissociated such that the Lys- and Arg-specific activities could be separated by eluting first with lysine then arginine, respectively. The 45 kDa protein of the complex was purified by further anion-exchange FPLC in the presence of octyl-beta-D-glucopyranoside and was shown to be an Arg-specific, thiol-activated, calcium-stabilized cysteine proteinase. The 48 kDa protein was also further purified in a similar fashion and shown to be a Lys-specific cysteine proteinase that was not inhibited by EDTA. The two 44 kDa and the 39, 27, 17 and 15 kDa proteins of the complex exhibit amino acid sequence homology and are proposed to be haemagglutinins/adhesins. The 45 kDa Arg-specific proteinase and one of the 44 kDa adhesins as well as the 15, 17 and 27 kDa adhesins are processed from the single polyprotein encoded by the gene designated prtR, with all proteins preceded by an Arg or Lys residue within the polyprotein. Similarly, the 48 kDa Lys-specific proteinase, the 39 and 15 kDa adhesins as well as the other 44 kDa adhesin of the 300 kDa complex are encoded by a single gene designated prtK, with all proteins preceded by an Arg or Lys residue within the polyprotein. The 39, 15 and 44 kDa adhesins of PrtK all exhibit high homology with the 44, 15, 17 and 27 kDa adhesins encoded by prtR, particularly the 15 kDa proteins which are identical. The cell-associated proteinase-adhesin complex, designated PrtR-PrtK, is therefore composed of the two gene products, the mature PrtR (160 kDa) and mature PrtK (163 kDa) that are further proteolytically processed (most likely autolytically) to release proteinase and adhesin domains that remain non-covalently associated. The fully processed PrtR-PrtK complex comprises the cysteine proteinases-PrtR45 and PrtK48 and seven sequence-related adhesin molecules, PrtR44, PrtR15, PrtR17, PrtR27 and PrtK39, PrtK15 and PrtK44. We propose that this proteinase-adhesin complex is a major virulence factor for P. gingivalis involved in the evasion of host defence and in the assimilation of haem and peptides.
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PMID:A cell-associated protein complex of Porphyromonas gingivalis W50 composed of Arg- and Lys-specific cysteine proteinases and adhesins. 924 29


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