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J Travis

Publications and source records attributed to J Travis.

At least 145 records · Page 8Linked to original sources
PubMed1994

Lysine- and arginine-specific proteinases from Porphyromonas gingivalis. Isolation, characterization, and evidence for the existence of complexes with hemagglutinins.

Porphyromonas gingivalis contains many virulence factors that have been implicated as participants in the progression of periodontal disease. It has been shown to produce proteinases of "trypsin-like" specificity in a number of molecular forms, but previous work in our laboratory resulted in the purification of a major arginine-specific cysteine proteinase, gingipain, which contradicted this supposed specificity. In this study, separate proteinases with arginine and lysine specificity were isolated from a high molecular mass fraction of the P. gingivalis culture fluid. The arginine-specific enzyme was found, by amino acid sequencing studies, to be a high molecular mass form of gingipain, formed by the 50-kDa gingipain noncovalently complexed with 44-kDa binding proteins, subsequently identified as hemagglutinins. The 60-kDa lysine-specific proteinase, referred to as Lys-gingipain, was also found to have one of these hemagglutinins complexed with it in the same manner. Lys-gingipain was found to be a cysteine proteinase with optimal activity and stability at pH 8.0-8.5 and was extensively characterized in terms of its specificity and activation characteristics. The proteinase-hemagglutinin complexes may be important in the uptake of hemin, a vital metabolite for P. gingivalis, via hemagglutination and subsequent hemolysis of erythrocytes.

Adhesins, Bacterial↗
PubMed1994

The isolation and partial characterization of alpha 1-proteinase inhibitor from the serum of the ostrich (Struthio camelus).

1. Native and cleaved alpha 1-proteinase inhibitor was purified from ostrich serum using Sepharose-blue dextran chromatography, ammonium sulfate precipitation and ion exchange chromatography on DEAE-Toyopearl 650 M at pH 8.8 and 6.5. Ostrich alpha 1-PI displayed M(r) values of 68,100 using gradient PAGE and 66,200 using Ferguson plots. Isoelectric focusing of ostrich alpha 1-PI in the pH range 3-10 revealed pI values of 4.84 and 4.91, and in the pH range 4-6 the characteristic microheterogeneity observed for mammalian alpha 1-PIs was displayed. The presence of sialic acid, hexoses and hexosamines was detected using chemical methods, but were found in much lower quantities as compared to alpha 1-PIs of other species. Western blot analysis demonstrated a positive reaction between the native and cleaved ostrich alpha 1-PIs and the antibodies to the ostrich alpha 1-PIs raised in rabbits. No cross-reactivity was demonstrated by Western blot analysis between human alpha 1-PI and antibodies to ostrich alpha 1-PI. The inhibitory effect of alpha 1-PI on elastase and chymotrypsin was also investigated.

Amino Acid Sequence↗
PubMed1994

The isolation and partial characterization of alpha 2-macroglobulin from the serum of the ostrich (Struthio camelus.

1. alpha 2-Macroglobulin (alpha 2M) activity is present in the serum of the ostrich, Struthio camelus. The chromogenic synthetic peptide substrates BAPNA and ATNA were hydrolysed by trypsin and chymotrypsin, respectively, in the presence of ostrich serum and the alpha 2 M in ostrich serum protected trypsin from being inhibited by soybean trypsin inhibitor. Ostrich alpha 2M proved to be a potent inhibitor of bovine pancreatic trypsin and chymotrypsin. 2. alpha 2M was purified to apparent homogeneity by PEG precipitation, DEAE-Toyopearl 650M, Bio-Gel A-5m and Zn(2+)-affinity chromatography. 3. Ostrich alpha 2M migrated as a single band (M(r) 779,000 during non-denaturing gradient gel electrophoresis and showed increased mobility after reaction with trypsin. Denaturation dissociated ostrich alpha 2M into half-molecules. Denaturation with reduction further dissociated the protein into quarter-subunits. 4. Isoelectric focusing revealed a pI of 5.3. 5. The amino acid composition of ostrich alpha 2M is typical of an alpha 2M, comparing favourably with those of other animal species. The carbohydrate composition of the purified protein, in percentage dry weight of the molecule, was galactose: mannose (1:1), 4.55; N-acetylglucosamine 2.35; N-acetylneuraminic acid, 0.58; and fucose, 0.77. 6. alpha 2M was assessed immunologically by Ouchterlony double-diffusion and Western blot analysis with polyvalent antisera directed against ostrich alpha 2M. 7. Ostrich alpha 2M seems to show many physical, chemical and kinetic properties similar to those of other known alpha 2M(s), but is expected to differ from other alpha Ms when considering the primary structure of the bait region, the area differing among alpha Ms from different species and determining its specificity.

Amino Acid Sequence↗
PubMed1994

The role of proteolytic enzymes in the development of pulmonary emphysema and periodontal disease.

Pulmonary emphysema and periodontal disease are each characterized by the uncontrolled proteolysis of connective tissue proteins by proteinases derived from human neutrophils. Although these diseases would not appear to be related in terms of the initial insult to individual tissues, the ultimate result in each disease is the accumulation and degranulation of neutrophils at inflammatory sites, apparently as a result of frustrated phagocytosis and specific activation of these phagocytic cells. This result is easily recognized in the case of emphysema, where there is clear evidence that the primary cause of the disease is the accumulation of foreign materials in the lung (e.g., smoke condensate), followed by the recruitment of neutrophils to the organ and the release of oxidative and hydrolytic enzymes. In periodontitis, however, the problem begins with the accumulation of plaque at the base of the teeth, followed by the growth of opportunistic anaerobic bacteria below the gum line. These parasitic microbes, which are resistant to killing by both monocytes and granulocytes, secrete proteinases that can activate the kallikrein-kinin pathway, degrade clotting factors, and release the potent neutrophil chemotactic factor, C5a, from complement. It is under such conditions that neutrophils are recruited to infected sites within the periodontium. After the neutrophil-recruitment stage, the two diseases become similar in that degranulation of neutrophils occurs during attempted phagocytosis of either cigarette smoke components (emphysema) or bacteria (periodontitis), followed by inactivation of tissue proteinase inhibitors and degradation of connective tissue proteins, the ultimate result being the destruction of the alveolus or gingiva, respectively.

Animals↗
PubMed1994

Pathogenesis of periodontitis: a major arginine-specific cysteine proteinase from Porphyromonas gingivalis induces vascular permeability enhancement through activation of the kallikrein/kinin pathway.

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.

Adhesins, Bacterial↗
PubMed1994

Comparison of properties of membrane bound versus soluble forms of human leukocytic elastase and cathepsin G.

Stimulation of human neutrophils with micromolar concentrations of N-formyl-methionyl-leucyl-phenyl-alanine (fMLP) or 4 beta-phorbol-12 beta-myristate-13 alpha-acetate (PMA), results in their degranulation and/or lysis with a concomitant release of Human Leucocyte Elastase (HLE; EC 3.4.21.37), Cathepsin G (cat G; EC 3.4.21.20) and Myeloperoxidase (MPO; EC 1.11.1.7) into the surrounding medium, some of which re-bind in an active form to neutrophil plasma membranes or membrane fragments. Histones, when present in the medium, prevent this association indicating that it is largely charge dependent. Bound proteinases have an increased resistance to inhibition by protein proteinase inhibitors, while bound MPO retains its ability to oxidatively inactivate alpha-1-proteinase inhibitor (alpha-1-PI). The attachment of oxidases and proteinases to plasma membrane or its fragments may allow them to remain active in an environment replete with proteinase inhibitors and, therefore, may be responsible for neutrophil or neutrophil-debris mediated tissue damage.

Amino Acid Sequence↗
PubMed1994

Interactions of alpha-1-antichymotrypsin, alpha-1-proteinase inhibitor, and alpha-2-macroglobulin with the fungal enzyme, seaprose.

The Semi-alkaline proteinase (Seaprose) from Aspergillus melleus has been tested for its ability to either inactivate or form complexes with three human plasma proteinase inhibitors, alpha-2-macroglobulin, alpha-1-antichymotrypsin and alpha-1-proteinase inhibitor. alpha-2-Macroglobulin was found to inhibit Seaprose, with two mol of enzyme being complexed per mol of inhibitor. However, alpha-1-proteinase inhibitor was rapidly inactivated by the fungal enzyme as a result of cleavage of the inhibitor, primarily at the P1-P'1 reactive site. Curiously, alpha-1-antichymotrypsin was found to form complexes with Seaprose and also be inactivated by this inhibitor. Apparently, the enzyme can recognize two sites within the reactive site loop of the inhibitor, one at the P4-P'5 position, resulting in inactivation, and one presumably at the P1-P'1 reactive site which results in complex formation. The fact that Seaprose can so rapidly inactivate alpha-1-proteinase inhibitor, the primary regulator of neutrophil elastase, indicates that Seaprose would be a rather poor choice for therapy in individuals with bronchial mucus hypersecretion.

Amino Acid Sequence↗
PubMed1994

Detection of Porphyromonas gingivalis in gingival exudate by a dipeptide-enhanced trypsin-like activity.

Porphyromonas gingivalis in subgingival plaque is an important risk factor for future periodontal attachment loss in susceptible adults. The elimination of P. gingivalis is usually concomitant with a healing process. Therefore, it should be valuable to have an easy chairside method to follow the effect of periodontal treatment on P. gingivalis detection as well as on its eventual reappearance during the maintenance period. We have previously reported the stimulation of amidolytic activity of P. gingivalis by the addition of glycyl-glycine to the assay buffer. In this study we determined the proportions of P. gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Capnocytophaga spp, Campylobacter rectus, and Eikenella corrodens by cultivation technique and the amidolytic activity, using N-benzoyl-L-arginine-p-nitroanilide (BAPNA) as substrate, in gingival exudate before and during a 3-year treatment and maintenance period. P. gingivalis was the only species yielding a high and persistent correlation to stimulated amidolytic activity (P values < or = 0.0001) on both site (r = 0.5) and subject (r = 0.8) level. Testing pure cultures of suggested periodontal pathogens for effect of glycyl-glycine on amidolytic activity, we found that of P. gingivalis to be 5.9-fold increased. The amidolytic activity of Treponema denticola was only slightly stimulated (ratio with/without glycyl-glycine = 1.2) and that of Capnocytophaga slightly inhibited (ratio with/without glycyl-glycine = 0.8). The outcome of this study has the potential to be used for the development of a simple, rapid, and inexpensive assay for a qualitative and quantitative determination of P. gingivalis in gingival crevicular fluid.

Adult↗
PubMed1994

Origin of circulating acute phase cytokines: modified proteins may trigger IL-6 production by macrophages. Preliminary report.

Human peripheral blood monocytes isolated by centrifugation with Mono-Poly resolving medium, and human alveolar macrophages obtained by lung lavage during fiberoscopic bronchoscopy, were cultured in RPMI containing 2% foetal calf serum. The cultures were exposed to modified human proteins: alpha-1-antitrypsin cleaved with papain, fibrinogen degradation products (fraction D) purified from plasmin digest, and non-enzymatically glycosylated (glycated) serum albumin. Conditioned macrophage media were tested for the contents of acute phase cytokines by bioassay with hepatoma cells, and the concentration of interleukin-6 was determined with ELISA. Modified proteins stimulated macrophages to produce acute phase cytokines and the response was not abrogated by polymyxin B in distinction to stimulation of macrophages by endotoxin. Our data indicate that some proteolytically damaged proteins or the end glycosylation products formed in pathological states (acute inflammation, diabetes) may be responsible for the appearance of cytokines in the circulation.

Amino Acid Sequence↗
PubMed1994

Working healthier.

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Adaptation, Psychological↗
PubMed1994

Simultaneous interphase cytogenetic analysis and fluorescence immunophenotyping of dedifferentiated chondrosarcoma. Implications for histopathogenesis.

Cytogenetic analysis of four specimens (biopsy, definitive surgical, and two separately occurring lung metastases) of a dedifferentiated chondrosarcoma with a rhabdomyosarcomatous component revealed clonal karyotypic abnormalities in each. Anomalies seen in all specimens included a structurally aberrant chromosome 17 and extra copies of chromosomes 5, 7, 12, and 20. The derivation of the chromosomally abnormal cells was determined by a combined immunocytochemical/cytogenetic approach that allowed simultaneous assessment of cytogenetic aberrations and immunophenotypic features of individual cells. S-100 protein and desmin antibodies were used to evaluate the chondrosarcomatous and rhabdomyosarcomatous components, respectively. A chromosome 7-specific centromeric probe was used for determination of aneuploidy. In both specimens obtained from the primary lesion, S-100 protein and desmin-positive and -negative aneuploid cells were observed. These findings: 1) suggest that both the chondrocytic and rhabdomyoblastic cells arose from the same abnormal clone, 2) support the theory of a common primitive mesenchymal cell progenitor with the ability to differentiate or express features of more than one line of mesenchymal differentiation, and 3) indicate that the term dedifferentiated may be an inaccurate designation for this neoplasm.

Bone Neoplasms↗