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

It seems from the literature that colloidal iron (C.I.) binding sites on cell surfaces cannot be completely removed by treatment with Vibrio Colerae alpha-neuraminidase. We wondered if C.I. particles bind to negative groups other than the carboxyl groups of sialic acids. Using HeLa cells from suspension cultures and fresh human erythrocytes, we examined, with the transmission electronmicroscope, the influence of the following enzymatic and histochemical treatments on C.I. staining: alpha-neuraminidase; hyaluronidase; ribonuclease; alpha-amylase; mild methylation (MM); MM + saponification (Sap.); MM + Sap +MM; MM + Sap + alpha-neuraminidase; active methylation (AM); AM + Sap; AM + Sap + AM; AM + Sap + alpha-neuraminiadase; CH3OH (80%); Sap. It seemed from these experiments that the carboxyl groups of alpha-neuraminidase sensitive sialic acids constitute the majority of binding sites for C.I. to these particular cells. The most interesting candidates for the residual binding of C.I. are carboxyl groups of alpha-neuraminidase resistant molecules, sulfon, sulfin, and sulfate groups.
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PMID:Cytochemistry of colloidal iron binding to the surface of Hela cells and human erythrocytes. 6 32

A polysaccharide antigen was isolated from Schistosoma mansoni egg homogenates by the phenol procedure. The crude preparation (CPEA) contained at least two antigens. The more purified antigen (PEA) was isolated by sequential enzymatic treatment of CPEA with DNase, RNase, Pronase, and alpha-amylase. PEA was resistant to boiling, freezing and thawing, mild acid and alkali, and chloroform, but was destroyed with periodate. It gave a positive reaction with anthrone reagent. PEA was eluted in the wash fraction from a DEAE cellulose collumn and in the void volume of a Sephacryl 200 column. After immunoelectrophoresis and polyacrylamide electrophoresis there was little or no migration. Amino acid analysis failed to reveal ninhydrin-positive material in the a hydrolyzate of PEA. These resluts suggested that PEA is a neutral polysaccharide with a m.w. of more than 200,000 and contains no amino acids or hexosamine. Antibodies against PEA were detected in sera obtained from mice infected with S. mansoni. PEA is different from previously described antigens derived from schistosome eggs.
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PMID:Isolation of a polysaccharide antigen from Schistosoma mansoni eggs. 10 42

On the basis of morphological and biochemical differences, the exocrine pancreatic tissue has been divided in peri- and teleinsular regions. In the present study the enzymatic profile of these regions has been investigated by the immunofluorescent technique using antibodies against nine pancreatic enzymes (alpha-amylase, lipase, chymotrypsinogen A, trypsinogen, elastase, carboxypeptidase A and B, DNase and RNase A). These antibodies were specific to their antigens without cross reaction. By immunofluorescence, most acinar cells of the normal rat pancreas were positive to the nine enzymes tested. However, an inhomogeneity in the staining pattern was found; specifically, the cells located in the periinsular region of many islets showed a brighter fluorescence than acinar cells in the teleinsular tissue. These data add a new parameter to describe the inhomogeneity of the exocrine pancreas.
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PMID:Immunohistochemical localization of exocrine enzymes in normal rat pancreas. 11 Aug 72

The content of proteins and nucleic acids and activity of acid and alkaline proteases, RNases, phosphatases and alpha-amylase were studied in the gum and alveolar bone or rats at the age of 1, 3, 6, 12, 18 and 24 months. It is found that a degree of periodontal atrophy strongly and directly correlates with the age of rats. The concentration of DNA and RNA in alveolar bone and of RNA in gum decreases with the age. The hydroxyproline content of periodontal tissues continuously increases till the age of 18th month and then considerably decreases. The activity of trypsin-like proteases, cathepsins and alkaline RNase in periodontal tissues increases reaching the maximum at the age of 6-18 months, and the activity of alkaline phosphatase decreases in the process of aging.
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PMID:[Biochemical properties of aging of rat periodontium]. 20 87

Suspensions of rat pancreatic microsomal fraction release alpha-amylase and ribonuclease on incubation at 37 degrees C, but not at 2 degrees C. The release is abolished by proteolytic enzymes. Ribonuclease associated with the microsomal fraction is protected from subtilisin BPN' attack, but is sensitive after release.
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PMID:Proteinase-sensitive release of enzymes from pancreatic microsomal fraction. 31 Nov 98

Intact ribonucleic acid (RNA) has been prepared from tissues rich in ribonuclease such as the rat pancreas by efficient homogenization in a 4 M solution of the potent protein denaturant guanidinium thiocyanate plus 0.1 M 2-mercaptoethanol to break protein disulfide bonds. The RNA was isolated free of protein by ethanol precipitation or by sedimentation through cesium chloride. Rat pancreas RNA obtained by these means has been used as a source for the purification of alpha-amylase messenger ribonucleic acid.
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PMID:Isolation of biologically active ribonucleic acid from sources enriched in ribonuclease. 51 35

A heterobifunctional reagent, N-succinimidyl 3-(2-pyridyldithio)propionate, was synthesized. Its N-hydroxysuccinimide ester group reacts with amino groups and the 2-pyridyl disulphide structure reacts with aliphatic thiols. A new thiolation procedure for proteins is based on this reagent. The procedure involves two steps. First, 2-pyridyl disulphide structures are introduced into the protein by the reaction of some of its amino groups with the N-hydroxysuccinimide ester sie of the reagent. The protein-bound 2-pyridyl disulphide structures are then reduced with dithiothreitol. This reaction can be carried out without concomitant reduction of native disulphide bonds. The technique has been used for the introduction of thiol groups de novo into ribonuclease, gamma-globulin, alpha-amylase and horseradish peroxidase. N-Succinimidyl 3-(2-pyridyldithio)propionate can also be used for the preparation of protein-protein conjugates. This application is based on the fact that protein-2-pyridyl disulphide derivatives (formed from the reaction of non-thiol proteins with the reagent) react with thiol-containing proteins (with native thiols or thiolated by, for example, the method described above) via thiol-disulphide exchange to form disulphide-linked protein-protein conjugates. This conjugation technique has been used for the preparation of an alpha-amylase-urease, a ribonuclease-albumin and a peroxidase-rabbit anti-(human transferrin) antibody conjugate. The disulphide bridges between the protein molecules can easily be split by reduction or by thiol-disulphide exchange. Thus conjugation is reversible. This has been demonstrated by scission of the ribonuclease-albumin and the alpha-amylase-urease conjugate into their components with dithiothreitol. N-Succinimidyl 3-(2-pyridyldithio)propionate has been prepared in crystalline form, in which state (if protected against humidity) it is stable on storage at room temperature (23 degrees C).
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PMID:Protein thiolation and reversible protein-protein conjugation. N-Succinimidyl 3-(2-pyridyldithio)propionate, a new heterobifunctional reagent. 70 70

Two criteria are suggested for assessing the relevance of biochemical events occurring early in sporulation. The first is thymidine starvation, a condition known to inhibit sporulation. This also inhibits the production of metalloprotease, serine protease, and ribonuclease; alpha-amylase production, however, is unaffected. The second is the effect of a regulator mutation which increases the production of the proteases. In the mutant, ribonuclease is produced in correspondingly large quantities whereas alpha-amylase production is unaffected. We conclude that, whereas the serine protease is part of the main sequence of events leading to formation of the spore, the metalloprotease is a side effect, i.e., connected with the main sequence but not part of it. Ribonuclease could, on present evidence, be either in the main sequence or a side effect associated with it. Amylase, however, seems to be separately regulated and neither directly nor indirectly connected with the sporulation sequence.
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PMID:Criteria for categorizing early biochemical events occurring during sporulation of Bacillus subtilis. 80 78

The diet and feeding patterns of developing rats were determined from feed bin weight losses and analysis of stomach contents (details in a previous report). Parotid gland development in the same rats was assessed from the specific activities of the secretory enzymes alpha-amylase, RNase and DNase, with particular attention to the occurrence of circadian variations. The results indicate that during the first week post partum, rats suckle much more by day than by night but have no circadian cycles in their parotid glands. Between 10 and 20 days, there were no consistent cycles either in feeding activity or in parotid enzymes. The progressive change from milk to stock diet between 14 and 30 days appears to promote the maturation of the parotid gland. The halfway point in the dietary change at 21 days coincides with the onset of inversely related circadian cycles in feeding and the parotid enzymes. Premature weaning at 21 days accentuates both cycles and accelerates parotid maturation. The findings indicate that the physical consistency of the diet has an imporant regulatory role in the developmental patterns of feeding activity and parotid glands of rats, but they also hint that other dietary qualities may be involved. Chronologic fluctuations in plasma corticosterone suggest an intricate relationship among this hormone, feeding behavior, and parotid glands in developing rats.
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PMID:Changes in patterns of feeding activity, parotid secretory enzymes and plasma corticosterone in developing rats. 95 13

Using isopycnic density gradient centrifugation, lysosomes were concentrated in a single region of a sucrose-Ficoll gradient (p = 1-10 g cm-3), well separated from most other cell organelles. Gibberellic acid-induced lysosomes were found to be rich in alpha-amylase and protease but not ribonuclease. The lysosomal band also contained a majority of the NADH2-cytochrome c reductase, a marker enzyme for endoplasmic reticulum, found in the gradient. Examination of electron micrographs revealed that a purified band of lyosomes contained at least 3 vesicle types, ranging in size from 0-1 to 0-5 mum. The significance of these findings to proposed mechanisms of action of gibberellic acid is discussed.
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PMID:Purification of gibberellic acid-induced lysosomes from wheat aleurone cells. 100 75


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