Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.4 (trypsin)
 42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Neutral protease, collagenase and elastase activities were high in synovial fluids from inflammatory arthritic diseases such as gout, active rheumatoid arthritis and ankylosing spondylitis. The activities correlated well with biochemical parameters such as CRP, ESR and total protein. Values were much lower in a non-inflammatory fluid from a patient with osteoarthrosis. Treatment of fluids with trypsin released both collagenase and elastase. The fluids possessed reserve inhibitory action against these enzymes presumably due to plasma antiproteases being present. The collagenase present was found to possess a MW of 32,700 daltons.
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PMID:Neutral protease, collagenase and elastase activities in synovial fluids from arthritic patients. 609 75

Chemical modification and electron spin resonance techniques were used to study the topography of carboxyl residues in purple membranes. The results showed that buried carboxyl groups are located in hydrophobic protein domains at least 16 A from the membrane surface, and that the carboxyl-terminal tail is partially immobilized. Carboxyl groups on bacteriorhodopsin in purple membranes were covalently spin-labeled with 4-amino-2,2,6,6-tetramethylpiperidine-N-oxyl using N-(ethoxycarbonyl)-2-ethoxy-1,2-dihydroquinoline as a highly specific coupling agent. Spin-labeled bacteriorhodopsin preparations containing an average of 2.1 +/- 0.5 spins/molecule retained photocycling and proton-pumping functions. Accessibility to the paramagnetic broadening agents, Fe(CN)3-6 and Ni2+, revealed a highly mobile surface group quenched at low concentrations of these agents, and a buried, immobilized group whose ESR signal remained at high quencher concentration. Treatment with denaturing agents greatly increased the mobility and quenching of these buried residues. A series of stearic acid spin labels bound to purple membranes was used to define the depth of paramagnetic interactions. Fe(CN)3-6 interactions were limited to surfaces whereas Ni2+ and Cu2+ effects extended into hydrophobic domains. A double modification procedure, which first blocked surface groups, selectively spin-labeled only buried carboxyl group(s) having a strongly immobilized signal. ESR analysis of the isolated carboxyl-terminal tail after trypsin treatment showed it had increased mobility, indicating that it is moderately immobilized in the native structure. These data provide evidence consistent with several models of bacteriorhodopsin tertiary structure which place carboxyls within hydrophobic domains of the protein.
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PMID:Topographic studies of spin-labeled bacteriorhodopsin. Evidence for buried carboxyl residues and immobilization of the COOH-terminal tail. 630 88

The uptake of ganglioside analogues by a permanent mouse fibroblast cell line has been studied by radio-tracer techniques and ESR spectroscopy with 3H- and nitroxide-labeled compounds. Analogues of GM1, GM2, and GM3 monosialogangliosides and of GD1a and GD3 disialogangliosides were synthesized. The spin-label group was situated on the 5-, 9-, or 13-carbon atom of the C18 fatty acid chain, and the 3H label was in the carbohydrate moiety. Part of the ganglioside associated with the cells could be removed by trypsin treatment and was shown to consist of ganglioside micelles attached to the cell surface. The trypsin-resistant component displayed characteristic anisotropic ESR spectra which closely resembled those of the same spin-labeled analogues at low dilution in liposomes prepared from the extracted cell lipids. The flexibility gradient, polarity profile, and temperature dependence displayed by the spectra were similar to those found for fluid phospholipid bilayer model membranes, and the high effective order parameters suggested a location in the cell plasma membrane. Similar results were obtained for all the different ganglioside analogues, indicating a common anchoring region in the hydrophobic interior of the membrane. Under the incubation conditions used the amount of trypsin-resistant ganglioside analogue taken up by the cells was about 15 nmol/mg of cellular protein, irrespective of the nature of the oligosaccharide moiety. By use of the natural ganglioside [3H]GM3, the trypsin-resistant uptake was about 19 nmol/mg of cellular protein. Although these amounts are quite similar, the uptake kinetics differed between the true ganglioside GM3 and the ganglioside analogues.
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PMID:Incorporation of ganglioside analogues into fibroblast cell membranes. A spin-label study. 631 58

In the present study we examined the structural integrity of the myelin sheath in the peripheral nerves from short-term streptozotocin (STZ)-treated diabetic rats, using ESR spectroscopy as a tool in determining the dynamic state and the structure of the myelin lipid phase. Experiments were performed on spin-labeled sciatic and sural nerves from STZ-treated Hannover-Wistar rats and age-matched controls. The spectrum analysis employed a numerical simulation model with the set of fitting parameters that in the same time relate the ESR line shape and structure and dynamics of the probed environment. The simulation considered three spectral components weighted and summed in the composite spectrum. The comparative analysis of results showed the fraction of the spectral component II to be significantly increased in the spectra of diabetic rats, indicating the significant increase in overall fluidity of the myelin structure. The origin of fluidity changes was further investigated using an experimental model for demyelination (local injection of ethidium bromide in vivo), proteolytic action of trypsin in vitro, and osmotic myelin swelling in vitro. Analysis and comparison of the results suggested a conclusion in terms of changed biophysical properties of the myelin lipid phase in peripheral nerves in the pathology of diabetes.
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PMID:Fluidity of the myelin sheath in the peripheral nerves of diabetic rats. 1156 54

A prolyl endopeptidase inhibitor was isolated from the ethyl acetate soluble fraction of Phyllanthus ussurensis. The active compound was identified as an ellagitannin, corilagin. It was shown to non-competitively inhibit prolyl endopeptidase (PEP) with the IC50 value of 1.17x10(-6) microM. The Ki value was 6.70x10(-7) M. Corilagin was less inhibitory to other serine proteases such as chymotrypsin, trypsin, and elastase, indicating that it was relatively a specific inhibitor of PEP. Corilagin also effectively inhibited reactive oxygen species such as hydroxide and superoxide anion radical, hydrogen peroxide, and DPPH. Especially, corilagin showed potent scavenging activity on the superoxide anion radical in the ESR method (IC50 = 3.79x10(-6) M) as well as xanthine oxidase system.
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PMID:A prolyl endopeptidase-inhibiting antioxidant from Phyllanthus ussurensis. 1472 35


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