14 results on '"Dekker, C. A."'
Search Results
2. Ribonucleases of human cerebrospinal fluid: detection of altered glycosylation relative to their serum counterparts.
- Author
-
Schieven GL, Blank A, and Dekker CA
- Subjects
- Animals, Cattle, Chromatography, Gel, Electrophoresis, Polyacrylamide Gel, Humans, Leukocytes enzymology, Molecular Weight, Pancreas enzymology, Ribonucleases blood, Carbohydrates analysis, Ribonucleases cerebrospinal fluid
- Published
- 1982
- Full Text
- View/download PDF
3. Differences in glycosylation pattern of human secretory ribonucleases.
- Author
-
Beintema JJ, Blank A, Schieven GL, Dekker CA, Sorrentino S, and Libonati M
- Subjects
- Amino Acid Sequence, Carbohydrates analysis, Glycopeptides analysis, Glycosylation, Humans, Male, Molecular Sequence Data, Pancreas enzymology, Ribonucleases analysis, Ribonucleases urine, Semen enzymology, Ribonucleases metabolism
- Abstract
The major secretory ribonuclease (RNase) of human urine (RNase HUA) was isolated and sequenced by automatic Edman degradation and analysis of peptides and glycopeptides. The isolated enzyme was shown to be free of other urine RNase activities by SDS/polyacrylamide-gel electrophoresis and activity staining. It is a glycoprotein 128 amino acids long, differing from human pancreatic RNase in the presence of an additional threonine residue at the C-terminus. It differs from the pancreatic enzyme in its glycosylation pattern as well, and contains about 45 sugar residues. Each of the three Asn-Xaa-Ser/Thr sequences (Asn-34, Asn-76, Asn-88) is glycosylated with a complex-type oligosaccharide chain. Glycosylation at Asn-88 has not been observed previously in mammalian secretory RNases. Preliminary sequence data on the major RNase of human seminal plasma have revealed no difference between it and the major urinary enzyme; their similarities include the presence of threonine at the C-terminus. The glycosylation pattern of human seminal RNase is very similar to that of the pancreatic enzyme. The structural differences between the secretory RNases from human pancreas, urine and seminal plasma must originate from organ-specific post-translational modifications of the one primary gene product. Detailed characterization of peptides and the results of gel filtration of tryptic and tryptic/chymotryptic digests of performic acid-oxidized RNase have been deposited as Supplementary Publication SUP 50146 (4 pages) at the British Library Lending Division, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1988) 249, 5.
- Published
- 1988
4. Synthesis of nucleoside 3'-(S-alkyl phosphorothioates) and their use as substrates for nucleases.
- Author
-
Saba D and Dekker CA
- Subjects
- Animals, Cattle, Endonucleases metabolism, Indicators and Reagents, Kinetics, Pancreas enzymology, Ribonuclease T1 metabolism, Ribonuclease, Pancreatic, Structure-Activity Relationship, Substrate Specificity, Endoribonucleases, Organothiophosphates chemical synthesis, Organothiophosphorus Compounds chemical synthesis, Ribonucleases metabolism, Thionucleotides chemical synthesis
- Abstract
The synthesis of cytidine, uridine, guanosine, and adenosine 3'-(S-methyl phosphorothioates) by treatment of the 2',5'-di-O-(4-methoxytetrahydropyran-4-yl)ribonucleosides with 2-(methylthio 4H-1,3,2-benzodioxaphosphorin 2-oxide is described. These nucleotide analogues are stable compounds both in the solid state and the neutral aqueous solution. All four of these compounds are degraded by RNase T2 to the parent nucleotides and methanethiol. In addition, cytidine and uridine 3'-(S-methyl phosphorothioates) are substrates for bovine pancreatic ribonuclease and guanosine 3'-(S-methyl phosphorothioate) is a substrate for RNase T1 and RNase U1. When used in conjunction with a chromophore-producing reagent, nucleoside 3'-(S-methyl phosphorothioates) provide a means for direct kinetic measurement of ribonuclease activity over a wide pH range (pH 2-9). The reactivities of these substrates with ribonucleases are compared to the reactivities of other synthetic substrates as well as a number of natural substrates. The utility of ribonucleoside 3'-(S-methyl phosphorothioates) as substrates for the assay of ribonucleases is discussed.
- Published
- 1981
- Full Text
- View/download PDF
5. Ribonucleases of human serum, urine, cerebrospinal fluid, and leukocytes. Activity staining following electrophoresis in sodium dodecyl sulfate-polyacrylamide gels.
- Author
-
Blank A and Dekker CA
- Subjects
- Electrophoresis, Polyacrylamide Gel, Humans, Indicators and Reagents, Kinetics, Ribonucleases urine, Sodium Dodecyl Sulfate, Leukocytes enzymology, Ribonucleases blood
- Abstract
The ribonucleases (RNases) of human blood serum, urine, cerebrospinal fluid (CSF), and leukocytes were visualized by activity staining after electrophoresis in RNA-case sodium dodecyl sulfate-polyacrylamide gels. Samples were prepared for electrophoresis by heating for 2 min at 100 degrees C in 2% sodium dodecyl sulfate (NaDodSO4) and 5% mercaptoethanol, conditions which dissociate proteins into their constituent polypeptide chains and permit estimation of molecular weight. It was found that each of the five peaks of serum alkaline RNase activity separable on phosphocellulose columns, i.e., RNases 1-5 of Akagi et al. [Akagi, K., Murai, K., Hirao, N., & Yamanaka, M. (1976) Biochim. Biophys. Acta 442, 368-378], is associated with electrophoretically distinct enzymes. The molecular weights exhibited by these enzymes in NaDodSO4 gels are 31 000 and 28 000 (major species of RNase 1), 25 000 (RNase 2), 20 000 (RNase 3), 16 000 (RNase 4), and 14 000 (RNase 5). The RNase activity of leukocytes displays a molecular weight of 17 000 and exhibits a characteristic dependence of its Rf on the temperature at which samples (in 2% NaDodSO4 without mercaptoethanol) are prepared for electrophoresis. An RNase activity like that of leukocytes, distinct from RNases 1-5, is found in serum. Urine RNase activity is less heterogeneous than that of serum, consisting mainly of species like serum RNase 1 and an enzyme similar to leukocyte RNase. Conversely, CSF RNase activity is more complex and includes enzymes resembling serum RNases 1-5 as well as additional species either not observed in serum or detected in serum as minor components following chromatography. The analytical methods described herein are particularly useful for assessment of heterogeneity of RNase preparations and for direct comparison of the RNases of crude and purified samples.
- Published
- 1981
- Full Text
- View/download PDF
6. Differential activity staining: its use in characterization of guanylyl-specific ribonuclease in the genus Ustilago.
- Author
-
Blank A and Dekker CA
- Subjects
- Electrophoresis, Polyacrylamide Gel, Indicators and Reagents, Oligoribonucleotides, Species Specificity, Basidiomycota enzymology, Ribonuclease T1 metabolism, Ribonucleases metabolism, Ustilago enzymology
- Abstract
Guanylyl-specific ribonuclease can be identified by a novel technique employing electrophoresis in polyacrylamide slabs followed by differential activity staining. The technique requires as little as 7 ng of enzyme which may be grossly admixed with contaminants, including other ribonucleases. Upon electrophoresis and activity staining, a variety of ribonucleases can be visualized as light or clear bands in a colored background formed by toluidine blue complexed with oligonucleotide substrate. Guanylyl-specific ribonuclease, which is detectable when using an oligonucleotide substrate of random base sequence, does not yield a band when using oligonucleotides bearing guanylyl residues at the 3'-termini only and containing, therefore, no susceptible internucleotide bonds; in contrast, a ribonuclease with a different base specificity or no base specificity yields a band with either substrate. This differential activity staining method for establishing guanylyl specificity permits estimation of the extent of nonspecific cleavage of internucleotide linkages by a putatively guanylyl-specific enzyme and is at least as sensitive as conventional procedures for determination of base specificity. With this new technique guanyloribonuclease has been identified in the unfractionated culture medium of 10 organisms belonging to the phytopathogenic fungal genus Ustilago. It is suggested that guanylyl-specific ribonuclease is widely distributed among Ustilago species; its electrophoretic properties may be revealing of phylogenetic relationships among these plant parasites and among their hosts. The general technique of differential activity staining, developed for determination of the base specificity of ribonucleases, may be widely applicable to analysis of enzymes catalyzing depolymerization reactions.
- Published
- 1975
- Full Text
- View/download PDF
7. Multiple ribonucleases of human urine.
- Author
-
Sugiyama RH, Blank A, and Dekker CA
- Subjects
- Electrophoresis, Polyacrylamide Gel, Humans, Indicators and Reagents, Leukocytes enzymology, Molecular Weight, Reference Values, Ribonucleases blood, Isoenzymes urine, Ribonucleases urine
- Abstract
Four major urine ribonuclease (RNase) activities, designated bands A-D, were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and activity staining. Bands A, B, and C have alkaline pH optima and display molecular weights of 31 000, 23 000, and 20 000, respectively, upon sodium dodecyl sulfate (NaDodSO4) gel electrophoresis and weights of 44 000, 28 000, 22 000 upon gel filtration. Band D, with a pH optimum slightly below neutrality, has a molecular weight of 16 000 or 15 000, respectively, determined by the above methods. Band A, the most abundant activity in urine, is heterogeneous and resembles serum RNase 1 on electrophoresis and on phosphocellulose and Sephadex chromatography. Band B is similar to a minor, unnamed component of serum RNase activity while band C resembles serum RNase 3. Band D is similar to the leukocyte RNase-like activity of serum [Blank, A., & Dekker, C.A. (1981) Biochemistry (preceding paper in this issue)]. Band A is present in urine at a concentration high than that of RNase 1 in serum. In contrast, urine counterparts of serum RNases 2, 4, and 5 are not apparent upon either phosphocellulose chromatography [see also Yamanaka, M., Akagi, K., Murai, K., Hirao, N., Fujimi, S., & Omae, T. (1977) Clin. Chim. Acta 78, 191-201] or NaDodSO4 get electrophoresis; a urine counterpart of serum RNase 3 can be detected only by the more sensitive electrophoretic method. These results indicate that RNase 2-5 are processed differently by the kidney than RNase 1. After reconciliation of reported differences in their pH optima and molecular weights, five apparently diverse RNase preparations described in the literature can be related to band A activity and three preparations to band D. However, we are unable to confirm a previous report of a human urine enzyme indistinguishable from bovine pancreatic RNase A.
- Published
- 1981
- Full Text
- View/download PDF
8. Ribonuclease U 1 . Physical and chemical characterization of the purified enzyme.
- Author
-
Kenney WC and Dekker CA
- Subjects
- Acetone, Amino Acids analysis, Ammonium Sulfate, Aspergillus enzymology, Basidiomycota drug effects, Basidiomycota growth & development, Chemical Precipitation, Chromatography, DEAE-Cellulose, Drug Stability, Electrophoresis, Disc, Enzyme Induction, Hot Temperature, Hydrogen-Ion Concentration, Iodoacetates, Molecular Weight, RNA pharmacology, Spectrophotometry, Ultracentrifugation, Ultraviolet Rays, Basidiomycota enzymology, Ribonucleases analysis, Ribonucleases antagonists & inhibitors, Ribonucleases biosynthesis, Ribonucleases isolation & purification
- Published
- 1971
- Full Text
- View/download PDF
9. Control by cesium and intermediates of the citric acid cycle of extracellular ribonuclease and other enzymes involved in the assimilation of nitrogen.
- Author
-
Holloman WK and Dekker CA
- Subjects
- Ammonia pharmacology, Chlorides pharmacology, Citrates pharmacology, Cycloheximide pharmacology, Dactinomycin pharmacology, Enzyme Induction, Fumarates pharmacology, Galactosidases biosynthesis, Glutarates pharmacology, Histidine, Lyases biosynthesis, Malates pharmacology, Mercaptopurine pharmacology, Methylamines pharmacology, Nitrates, Oxaloacetates pharmacology, Oxidoreductases biosynthesis, Phenylalanine pharmacology, Succinates pharmacology, Sucrase biosynthesis, Xanthine Oxidase biosynthesis, Cesium pharmacology, Citric Acid Cycle, Fungi enzymology, Nitrogen metabolism, Ribonucleases biosynthesis
- Abstract
Synthesis of extracellular ribonuclease is induced in cell cultures of Ustilago sphaerogena that are starved for nitrogen and exposed to the gratuitous inducer, 6-mercaptopurine. Cesium, ammonium, or alkylammonium ion represses ribonuclease induction. Addition of citric-acid cycle intermediates to cesium ionrepressed cultures partially restores the rate of ribonuclease synthesis to the induced level. Enzymes involved in assimilation of nitrogen from different sources are also repressed by cesium ion and derepressed by intermediates from the citric acid cycle.
- Published
- 1971
- Full Text
- View/download PDF
10. STUDIES ON A RIBONUCLEASE FROMUSTILAGO SPHAEROGENNA. II. SPECIFICITY OF THE ENZYME.
- Author
-
GLITZ DG and DEKKER CA
- Subjects
- Adenine Nucleotides, Chromatography, Cytosine Nucleotides, DNA, Fungi, Guanine Nucleotides, Metabolism, RNA, Research, Ribonucleases
- Published
- 1964
- Full Text
- View/download PDF
11. Ribonuclease U 4 from Ustilago sphaerogena. Purification and physical properties.
- Author
-
Blank A and Dekker CA
- Subjects
- Carbohydrates analysis, Chromatography, DEAE-Cellulose, Chromatography, Gel, Chromatography, Ion Exchange, Electrophoresis, Disc, Molecular Weight, Spectrophotometry, Ultraviolet, Ultracentrifugation, Basidiomycota enzymology, Ribonucleases analysis, Ribonucleases isolation & purification
- Published
- 1972
- Full Text
- View/download PDF
12. STUDIES ON A RIBONUCLEASE FROM USTILAGO SPHAEROGENA. I. PURIFICATION AND PROPERTIES OF THE ENZYME.
- Author
-
GLITZ DG and DEKKER CA
- Subjects
- Benzoates, Chlorides, Culture Media, Electrophoresis, Fungi, Magnesium, Pharmacology, Polyvinyls, Research, Ribonucleases, Sodium Chloride, Sulfates, Ultracentrifugation, Ustilago
- Published
- 1964
- Full Text
- View/download PDF
13. Ribonuclease U 4 . Novel phosphotransferases catalyzing exonucleolytic degradation of ribonucleic acid.
- Author
-
Blank A and Dekker CA
- Subjects
- Buffers, Catalysis, Chromatography, DEAE-Cellulose, Chromatography, Gel, Chromatography, Ion Exchange, Chromatography, Paper, DNA, Edetic Acid, Hydrogen-Ion Concentration, Nitrophenols, Nucleic Acid Denaturation, Organophosphorus Compounds, Phosphorus Isotopes, Structure-Activity Relationship, Urea, Basidiomycota enzymology, Exonucleases antagonists & inhibitors, Ribonucleases antagonists & inhibitors
- Published
- 1972
- Full Text
- View/download PDF
14. Differences in glycosylation pattern of human secretory ribonucleases
- Author
-
Beintema, J J, Blank, A, Schieven, G L, Dekker, C A, Sorrentino, S, and Libonati, M
- Subjects
Male ,Glycosylation ,Ribonucleases ,Semen ,Molecular Sequence Data ,Carbohydrates ,Glycopeptides ,Humans ,Amino Acid Sequence ,Pancreas ,Research Article - Abstract
The major secretory ribonuclease (RNase) of human urine (RNase HUA) was isolated and sequenced by automatic Edman degradation and analysis of peptides and glycopeptides. The isolated enzyme was shown to be free of other urine RNase activities by SDS/polyacrylamide-gel electrophoresis and activity staining. It is a glycoprotein 128 amino acids long, differing from human pancreatic RNase in the presence of an additional threonine residue at the C-terminus. It differs from the pancreatic enzyme in its glycosylation pattern as well, and contains about 45 sugar residues. Each of the three Asn-Xaa-Ser/Thr sequences (Asn-34, Asn-76, Asn-88) is glycosylated with a complex-type oligosaccharide chain. Glycosylation at Asn-88 has not been observed previously in mammalian secretory RNases. Preliminary sequence data on the major RNase of human seminal plasma have revealed no difference between it and the major urinary enzyme; their similarities include the presence of threonine at the C-terminus. The glycosylation pattern of human seminal RNase is very similar to that of the pancreatic enzyme. The structural differences between the secretory RNases from human pancreas, urine and seminal plasma must originate from organ-specific post-translational modifications of the one primary gene product. Detailed characterization of peptides and the results of gel filtration of tryptic and tryptic/chymotryptic digests of performic acid-oxidized RNase have been deposited as Supplementary Publication SUP 50146 (4 pages) at the British Library Lending Division, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1988) 249, 5.
- Published
- 1988
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