Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.64 (proteinase K)
 4,071 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have investigated the in vitro responsiveness of T cells from mistletoe-treated cancer patients and untreated donors to various preparations of mistletoe extracts. Proliferation of peripheral blood mononuclear cells from treated but not from untreated patients was observed in response to therapeutically used mistletoe extracts prepared from apple (mali) or pine (pini) host trees. The strongest proliferation was induced by vesicle preparation of mali extract. Using a newly developed flow cytometry assay (standard cell dilution assay), we determined that cell growth was restricted to CD4+ T cells. Analysis with a panel of monoclonal antibodies against variable regions of the T cell receptor beta chain (V beta) revealed an oligoclonal pattern of CD4+ T cell activation. These results indicate that therapeutic administration of mistletoe extracts sensitized a restricted set of CD4+ T lymphocytes in mistletoe-treated patients. Lymphocytes from untreated donors are only stimulated with heat-treated mistletoe extracts. The responding T cells are gamma delta T cells and express variable T cell receptor elements V gamma 9 and V delta 2. The gamma delta-stimulating activity of heat-treated mistletoe extracts is sensitive to treatment with alkaline phosphatase but not with proteinase K, indicating that the ligands are non-proteinaceous phosphate-containing compounds.
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PMID:Stimulation of the specific immune system by mistletoe extracts. 917 65

A highly purified hydrogenosomal fraction was obtained from Tritrichomonas foetus by differential and Percoll gradient centrifugations. Transmission electron microscopy and assay of the malic enzyme activity were used to evaluate the isolation method and the integrity of the organelle. The isolated hydrogenosomes showed the same morphology as observed in intact cells, including the presence of a peripheral vesicle with an electron-dense content. SDS-PAGE revealed the presence of several protein bands, with those of 120, 66, 60, 59, 48, 45, and 35 kDa as the major ones. The hydrogenosome membrane was solubilized with Triton X-100 leaving a fraction containing its matrix attached to the peripheral vesicle. Further treatment with proteinase K solubilized the matrix components, leaving a pure peripheral vesicle fraction. Enzymatic assay during all procedures suggested that malate dehydrogenase was localized in the hydrogenosomal membrane. SDS-PAGE showed that proteins of 66, 45 and 32 kDa were localized in the peripheral vesicle. Western blot analysis of all fractions using alkaline phosphatase-conjugated wheat germ agglutinin revealed the presence of glycoproteins, with a major one of 45 kDa, in the peripheral vesicle of the hydrogenosome.
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PMID:Purification and biochemical characterization of the hydrogenosomes of the flagellate protozoan Tritrichomonas foetus. 930 94

In situ hybridization techniques have rapidly become widely used by the molecular biologist for the localization of specific nucleic acid sequences in individual cells or tissues. We describe the demonstration of Sox gene mRNA in chick tissue that has been embedded in the plastic methyl methacrylate to permit the preparation of sections for high-resolution light microscopy. Polymerization of the plastic was induced by using either N,N-dimethylaniline or N,N-3,5-tetramethylaniline. The in situ hybridization technique used was non-isotopic and used a digoxigenin-labelled probe detected with an antibody bound to alkaline phosphatase, which was then localized using X-phosphate-Nitro BT as a substrate-chromogen mix. Various pretreatments of the tissue sections were investigated, including the use of proteinase K, and heat-mediated techniques using a microwave oven and a pressure cooker. The best results were produced using pressure cooking on tissue in which the plastic had been chemically polymerized with N,N-3,5-tetramethylaniline. For the demonstration of Sox 11, this combination had a critical influence on the staining results, but for Sox 21 all protocols used produced good staining.
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PMID:Non-isotopic in situ hybridization to detect chick Sox gene mRNA in plastic-embedded tissue. 934 59

A rapid and simplified protocol for in situ hybridization (ISH) with polymerase chain reaction (PCR)-derived single-stranded DNA probes and S1 nuclease revealed transcripts of bone matrix proteins on decalcified skeletal bone specimens. Mouse bone tissue was fixed with 4% paraformaldehyde, decalcified with 20% EDTA, and embedded in paraffin. Each pair of primers for reverse transcriptase -PCR was designed to amplify a 280-bp DNA fragment from the coding region of the mature protein of mouse osteonectin (ON) and a 320-bp fragment from the coding region of mouse osteopontin (OP). Initial PCR products were eluted, purified, and reamplified by unidirectional PCR in the presence of the digoxigenin (DIG)-labeled dUTP. ISH was carried out by proteinase K treatment, hybridization, and washing. The unhybridized single-stranded DNA probe was selectively removed by S1 nuclease treatment. Hybridized probes were visualized with the alkaline phosphatase-conjugated anti-DIG antibody. The transcripts of ON and OP were clearly detected on the thin sections of the decalcified bone. Because this protocol does not require cloning or in vitro transcription, reliable and stable ISH can be done in an ordinary laboratory equipped with a thermal cycler.
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PMID:In situ hybridization with polymerase chain reaction-derived single-stranded DNA probe and S1 nuclease. 993 Aug 78

The attachment of pathogenic microorganisms to host cells and tissues is often mediated through the expression of surface receptors recognizing components of the extracellular matrix (ECM). Here, we investigate the ability of Borrelia spirochaetes to bind the ECM constituent, fibronectin. Borrelia lysates were separated by SDS-PAGE, transferred to nitrocellulose and probed with alkaline phosphatase-labelled fibronectin (fibronectin-AP). Five of six Borrelia species and four of eight B. burgdorferi sensu lato isolates expressed one or more fibronectin-binding proteins. Borrelia burgdorferi isolate B31 expressed a 47 kDa (P47) fibronectin-binding protein that was localized to the outer envelope based on susceptibility to proteinase K. The interaction of P47 with fibronectin was specific, and the region of fibronectin bound by P47 mapped to the gelatin/collagen binding domain. P47 was purified by affinity chromatography, digested with endoproteinase Lys-C, and the peptide fragments analysed by liquid chromatography/tandem mass spectroscopy. A search of protein databases disclosed that the P47 peptide mass profile matched that predicted for the bbk32 gene product of B. burgdorferi isolate B31. The bbk32 gene was cloned into Escherichia coli, and the ability of recombinant BBK32 to bind fibronectin and inhibit the attachment of B. burgdorferi was demonstrated. The identification of BBK32 as a receptor for fibronectin binding may enhance our understanding of the pathogenesis and chronic nature of Lyme disease.
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PMID:Identification of a 47 kDa fibronectin-binding protein expressed by Borrelia burgdorferi isolate B31. 998 77

Recent reports that isolated Treponema pallidum outer membranes contain an ortholog for glycerophosphodiester phosphodiesterase (GlpQ) (D. V. Shevchenko, D. R. Akins, E. J. Robinson, M. Li, O. V. Shevchenko, and J. D. Radolf, Infect. Immun. 65:4179-4189, 1997) and that this protein is a potential opsonic target for T. pallidum (C. E. Stebeck, J. M. Shaffer, T. W. Arroll, S. A. Lukehart, and W. C. Van Voorhis, FEMS Microbiol. Lett. 154:303-310, 1997) prompted a more detailed investigation of its physicochemical properties and cellular location. [14C]palmitate radiolabeling studies of a GlpQ-alkaline phosphatase fusion expressed in Escherichia coli confirmed the prediction from DNA sequencing that the protein is lipid modified. Studies using Triton X-114 phase partitioning revealed that the protein's amphiphilicity is due to lipid modification and that a substantial portion of the polypeptide is associated with the T. pallidum peptidoglycan sacculus. Three different approaches, i.e., (i) proteinase K treatment of intact treponemes, (ii) indirect immunofluorescence analysis of treponemes encapsulated in agarose beads, and (iii) opsonophagocytosis of treponemes incubated with antiserum against recombinant GlpQ by rabbit peritoneal macrophages, confirmed that GlpQ is entirely subsurface in T. pallidum. Moreover, rabbits hyperimmunized with GlpQ were not protected against intradermal challenge with virulent treponemes. Circular dichroism spectroscopy confirmed that the recombinant form of the polypeptide lacked discernible evidence of denaturation. Finally, GlpQ was not radiolabeled when T. pallidum outer membranes were incubated with 3-(trifluoromethyl)-3-(m-[125I]iodophenyl)-diazarene, a photoactivatable, lipophilic probe which promiscuously labels both proteins and lipids within phospholipid bilayers. Taken as a whole, these studies indicate that the T. pallidum GlpQ ortholog is a periplasmic protein associated predominantly with the spirochete's peptidoglycan-cytoplasmic membrane complex.
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PMID:Membrane topology and cellular location of the Treponema pallidum glycerophosphodiester phosphodiesterase (GlpQ) ortholog. 1022 83

Subtilin is an antimicrobial peptide of the lantibiotic family that is produced by Gram-positive Bacillus subtilis, and its biosynthesis involves expression of presubtilin which consists of a leader segment and a mature segment. The leader segment is unlike a typical sec-type general secretion signal, and its ability to mediate translocation through a non-sec pathway has been previously studied by fusing the subtilin leader to an alkaline phosphatase reporter and expressing it in B. subtilis 168 [Izaguirre, G. and Hansen, J. N. (1997) Appl. Environ. Microbiol. 63, 3965-3971]. In this work, we have expressed the same subtilin leader-AP fusion in Gram-negative Escherichia coli, and found that the AP polypeptide is translocated into the periplasmic compartment and assembles into an enzymatically active form. The subtilin leader segment was not cleaved from this enzymatically active AP, which remained associated with the membrane. Conversion of the cells to spheroplasts followed by treatment with proteinase K showed that about 50% of the bound AP was sufficiently exposed on the surface of the spheroplasts to be inactivated by proteolytic cleavage.
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PMID:Studies of the subtilin leader peptide as a translocation signal in Escherichia coli K12. 1041 30

We investigated the ability of a virulent strain of Leptospira interrogans serovar icterohaemorrhagiae, its isogenic avirulent variant and a saprophytic strain to bind fibronectin using alkaline phosphatase-labelled fibronectin. A single 36-kDa fibronectin-binding protein was expressed only by the virulent strain and was located in the outer sheath according to proteinase K treatment results. The interaction of this protein with fibronectin was specific and the region of fibronectin bound to this potential adhesin overlapped the gelatin-binding domain. The inability of a RGDS synthetic peptide to inhibit the binding of fibronectin indicated that the cell-binding domain was not involved in this interaction. Considering the wide distribution of fibronectin within a host and the diversity of mammals involved in the epidemiology of leptospirosis, its implication in the cell attachment process of virulent leptospires is coherent with the multiplicity of target cells.
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PMID:Identification of a 36-kDa fibronectin-binding protein expressed by a virulent variant of Leptospira interrogans serovar icterohaemorrhagiae. 1073 1

The finding that Treponema pallidum, the syphilis spirochete, contains 12 orthologs of the Treponema denticola outer membrane major sheath protein has engendered speculation that members of this T. pallidum repeat (Tpr) family may be similarly surface exposed. In this regard, the TprK protein was reported to be a target of opsonic antibody and protective immunity and subject to immunologically driven sequence variation. Despite these findings, results from our previous analyses of treponemal outer membranes in concert with computer-based predictions for TprK prompted us to examine the cellular location of this protein. TprK-alkaline phosphatase fusions expressed in Escherichia coli demonstrate that TprK contains a signal peptide. However, opsonophagocytosis assays failed to indicate surface exposure of TprK. Moreover, results from three independent methodologies, i.e., (a) indirect immunofluorescence analysis of agarose-encapsulated organisms, (b) proteinase K treatment of intact spirochetes, and (c) Triton X-114 phase partitioning of T. pallidum conclusively demonstrated that native TprK is entirely periplasmic. Consistent with this location, immunization with the recombinant protein failed to induce either protective immunity or select for TprK variants in the rabbit model of experimental syphilis. These findings challenge the notion that TprK will be a component of an efficacious syphilis vaccine.
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PMID:The TprK protein of Treponema pallidum is periplasmic and is not a target of opsonic antibody or protective immunity. 1134 86

Aim-To develop methods of messenger RNA (mRNA) in situ hybridisation (ISH) for use with routinely processed bone marrow trephine biopsy specimens, decalcified using formic acid, and long term cultures in order to demonstrate sites of synthesis of mRNA encoding monocyte colony stimulating factor (M-CSF).Methods-Biotinylated oligonucleotide probes, directed against target sequences within M-CSF mRNA, were hybridised with sections from bone marrow trephine biopsy specimens and detected using Streptavidin-biotin alkaline phosphatase complex formation. Validation of results included demonstration of total mRNA and unrelated mRNA species in adjacent sections, with appropriate negative controls. Minor technical modifications were required to perform ISH with long term bone marrow cultures.Results-M-CSF mRNA was demonstrated successfully in trephine biopsy specimens and long term cultures. Biopsy specimens varied in their requirement for predigestion with proteinase K and in the strength of the final reaction product, presumably due to variation in fixation. M-CSF mRNA was present in myelocytes and promonocytes. No stromal production of M-CSF mRNA was detected in biopsy specimens. ISH using long term bone marrow cultures confirmed production of M-CSF mRNA by developing monocytes and macrophages. Weak M-CSF mRNA expression was also seen in stromal fibroblasts.Conclusions-ISH can be performed successfully with formic acid decalcified bone marrow trephine biopsy specimens and long term cultures. The presence of M-CSF mRNA in myelomonocytic cells suggests that an autocrine mechanism contributes to monocyte differentiation. The absence of detectable M-CSF mRNA in biopsy stroma and its presence in stromal fibroblasts within bone marrow cultures probably reflects reduced sensitivity of ISH following tissue fixation and processing.
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PMID:Sites of M-CSF messenger RNA production in bone marrow trephine biopsy specimens and long term cultures demonstrated by nonisotopic in situ hybridisation. 1669 73


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