Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.27.5 (RNase)
 17,967 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A rare case of mixed connective tissue disease (MCTD) with subacute transverse myelopathy and various neurological signs was reported. The patient, a 53 year-old woman, was admitted to our hospital with subacute progressive muscle weakness of left lower limb and sensory disturbance of bilateral lower extremities. At the age of 40, she suffered from sensory disturbance of her face, which improved in about three years. She had a high fever, Raynaud phenomenon, dyshydrosis on right side of her face at the age of 43. On the admission, physical examination revealed swollen fingers and telangiectasia of her face. Neurologically, she had transverse myelopathy at the level of Th6, bilateral trigeminal neuropathy, tonic, pupils, polyneuropathy and dyshydrosis. Laboratory examination showed positive antinuclear antibody, a high titer of antibody to RNase-sensitive components of extractable nuclear antigen, positive antinuclear RNP antibody and negative anti-Sm antibody. Her myelopathy improved with corticosteroid therapy, and ESR and the level of immunoglobulin were normalized. But, other neurological signs showed no improvement.
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PMID:[A case of mixed connective tissue disease with subacute transverse myelopathy]. 180 65

Characterization of OH-induced free radicals using 3'-UMP and poly(U) was performed by a method combining spin-trapping and radical chromatography. A N2O-saturated aqueous solution containing 3'-UMP and 2-methyl-2-nitrosopropane as a spin-trap was X-irradiated. The spin adducts generated by the reactions of OH radicals with 3'-UMP were separated by paired-ion HPLC and the separated spin adducts were identified by ESR spectroscopy. In the case of poly(U), the spin adducts were digested to oligonucleotides with RNase A and then separated and identified in the same manner as 3'-UMP. The free radicals observed for poly(U) were identical to those for 3'-UMP. The 5-yl radical and the 6-yl radical were identified as precursors of various oxidized products of the base moiety, and the 4'-yl radical and 5'-yl radical, formed by H-abstraction at the C-4' and C-5' positions of the sugar moieties, respectively, were identified as precursors of strand breaks. The 1'-yl radical, produced by H-abstraction at the C-1' position of the sugar moiety, was also identified. From the similarity of the free radicals of 3'-UMP and poly(U), it is suggested that the reactivities of OH radicals with nucleotides are identical to those in polynucleotides.
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PMID:OH-induced free radicals in 3'-UMP and poly(U): spin-trapping and radical chromatography. 282 71

ESR studies on spin-labeled amorphous RNase A as a function of varying concentrations of sorbed H2O and D2O will be presented. A relaxation analysis of saturation transfer (ST-)ESR spectra of 14N(1H) nitroxide spin-label molecules essentially fixed at amino acid residue His-105 will be given. A characteristic correlation has been observed between the microdynamic behavior--expressed by the rotational correlation times of the paramagnetic label--and the macroscopic thermodynamic entropy for the sorption process of H2O and D2O at RNase. This correlation is particularly pronounced at low water concentrations, vis., nH2O/nprotein less than or equal to 100. A significant difference in this concentration range exists between the two systems "RNase-H2O" and "RNase-D2O", which is manifested not only by the thermodynamic data but also by the microdynamic behavior extracted from the corresponding non-linear ESR absorption line shapes.
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PMID:Thermodynamic and magnetic resonance studies on the hydration of polymers: II. Protein-water interactions in powered ribonuclease. 283 82

A method is described for the measurement of dynamic property of RNase A by ESR under xeric conditions. The relationship between relative humidity and hydration degree of RNase A was determined by hydration isotherm. A solution of RNase A was allowed to react with a solution containing maleimide nitroxide label at 25 degrees, then was dialysed and lyophilized. The stable powder of RNase A - maleimide nitroxide label compound was put into the tubules, then was hydrated under different relative humidity for 11 days. After hydration, the tubules were closed and measured by ESR. The relationship between hydration value and A(max) was detected. The results showed that the lowest water content that could induce motion of RNase A by water is about 0.20 g of water per g of RNase A. That means the motion of RNase A molecule becomes detectable when there are 152 water molecules around one RNase A molecule.
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PMID:An ESR Study on the Effect of Hydration on the Dynamic Property of RNase A. 1211 Sep 11

Binding to cell membrane, followed by translocation into the cytosol and RNA degradation, is a necessary requirement to convert a ribonuclease into a cytotoxin for malignant tumor cells. In this paper, we investigate the membrane binding attitude of bovine seminal ribonuclease (BS-RNase) and its variant G38K-BS-RNase, bearing an enforced cluster of positive charges at the N-termini surface. By using a combination of biophysical techniques, including CD, SPR and ESR, we find for the two proteins a common, two-step mechanism of interaction with synthetic liposomes, an initial binding to the bilayer surface, driven by electrostatic interactions, followed by a shallow penetration in the lipid core. Protein binding effectively perturbs lipid packing and dynamics. Remarkably, the higher G38K-BS-RNase membrane interacting capability well correlates with its increased cytotoxicity for tumor cells. Overall, these studies shed light on the mechanism of membrane binding and perturbation, proving definitely the importance of electrostatic interactions in the cytotoxic activity of BS-RNase, and provide a rational basis to design proteins with anticancer potential.
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PMID:Enforcing the positive charge of N-termini enhances membrane interaction and antitumor activity of bovine seminal ribonuclease. 2185 56