THE SYNTHESIS AND PROPERTIES OF ADENOSINE-2′ DIPHOSPHATE AND ADENOSINE-3′ DIPHOSPHATE

1967 ◽  
Vol 45 (1) ◽  
pp. 89-99 ◽  
Author(s):  
R. E. J. Mitchel ◽  
D. C. Ward ◽  
G. M. Tener
Keyword(s):  
Trichloroacetic Acid ◽  
Deae Cellulose ◽  
Side Reaction ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Hydroxyl Groups ◽  
Chemical Methods ◽  
Cyclic Phosphate ◽  
Hydrolysis Of ◽  
Direct Hydrolysis

Adenosine-2′ diphosphate (A2'DP) and adenosine-3′ diphosphate (A3′DP) have been prepared by reaction between the corresponding mononucleotides with phosphoramidic acid in formamide. The products were isolated by ion-exchange chromatography on DEAE-cellulose and characterized by enzymic and chemical methods. A major side reaction in the synthesis is the phosphorylation of unprotected hydroxyl groups oil the nucleotides. A2′DP and A3′DP were found to be more labile than adenosine-5′ diphosphate, and to decompose at neutral pH by direct hydrolysis of the pyrophosphate bond as well as by formation of adenosine-2′,3′ cyclic phosphate. They are stable in 10% trichloroacetic acid at 0° for 10 minutes. Phosphomonoesterase degrades both to nucleosides by way of the corresponding nucleoside monophosphates. Ribonuclease T2does not attack A2′DP but degrades A3′DP to adenosine-3′ phosphate. Neither nucleotide is degraded by snake venom or spleen phosphodiesterases under conditions where oligonucleotides are completely hydrolyzed.

scholarly journals Preparation, purification and analyses of thirteen alkali-stable dinucleotides from ribonucleic acid

1970 ◽  
Vol 116 (4) ◽  
pp. 589-598 ◽  
Author(s):  
A. R. Trim ◽  
Janet E. Parker
Keyword(s):  
Nucleotide Sequence ◽  
Ion Exchange ◽  
Ribonucleic Acid ◽  
Deae Cellulose ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Spectroscopic Constants ◽  
Commercial Yeast ◽  
High Degree ◽  
Hydrolysis Of

Of the 16 alkali-stable dinucleotides known to be obtained by hydrolysis of commercial yeast RNA with alkali, 13 were prepared in quantities of the order of 10mg or more. The samples, with only one exception, contain at least 90% of dinucleotide, and spectroscopic constants and nucleotide-sequence determinations, although not conclusive, indicate a high degree of purity of these products. The small dinucleotide fraction in 150g of RNA hydrolysed with alkali (1–2% of the total nucleotides) was separated from the mononucleotides by stepwise ion-exchange chromatography on DEAE-cellulose columns and resolved into seven fractions containing from one to four different dinucleotides by electrophoresis on paper at pH3.0. These fractions were resolved into their constituent dinucleotides by chromatography in ammonium sulphate. Contamination of the products by impurities from the paper was minimized by washing it before using it for chromatography or electrophoresis and, by using a thick grade of paper (Whatman no. 17), it was possible to handle and purify relatively large quantities of nucleotides.

scholarly journals Adjustment of Hydrophobic Properties of Cellulose Materials

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1241
Author(s):  
Michael Ioelovich
Keyword(s):  
Ester Group ◽  
Hydroxyl Groups ◽  
Chemical Methods ◽  
Hydrophobic Properties ◽  
Cellulose Esters ◽  
Cellulose Modification ◽  
Polar Groups ◽  
Polar Substituents ◽  
Hydrolysis Of ◽  
Cellulose Materials

In this study, physicochemical and chemical methods of cellulose modification were used to increase the hydrophobicity of this natural semicrystalline biopolymer. It has been shown that acid hydrolysis of the initial cellulose increases its crystallinity, which improves hydrophobicity, but only to a small extent. A more significant hydrophobization effect was observed after chemical modification by esterification, when polar hydroxyl groups of cellulose were replaced by non-polar substituents. The esterification process was accompanied by the disruption of the crystalline structure of cellulose and its transformation into the mesomorphous structure of cellulose esters. It was found that the replacement of cellulose hydroxyls with ester groups leads to a significant increase in the hydrophobicity of the resulting polymer. Moreover, the increase of the number of non-polar groups in the ester substituent contributes to rise in hydrophobicity of cellulose derivative. Depending on the type of ester group, the hydrophobicity increased in the following order: acetate < propionate < butyrate. Therefore, tributyrate cellulose (TBC) demonstrated the most hydrophobicity among all studied samples. In addition, the mixed ester, triacetobutyrate cellulose (TAB), also showed a sufficiently high hydrophobicity. The promising performance properties of hydrophobic cellulose esters, TBC and TAB, were also demonstrated.

scholarly journals The isocitrate dehydrogenases of Acinetobacter lwoffi. Separation and properties of two nicotinamide–adenine dinucleotide phosphate-linked isoenzymes

1972 ◽  
Vol 130 (1) ◽  
pp. 211-219 ◽  
Author(s):  
Colin H. Self ◽  
P. David J. Weitzman
Keyword(s):  
Molecular Weight ◽  
Ph Dependence ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Molecular Size ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Low Concentrations ◽  
Stimulation Of

Two isoenzymes of NADP-linked isocitrate dehydrogenase have been identified in Acinetobacter lwoffi and have been termed isoenzyme-I and isoenzyme-II. The isoenzymes may be separated by ion-exchange chromatography on DEAE-cellulose, by gel filtration on Sephadex G-200, or by zonal ultracentrifugation in a sucrose gradient. Low concentrations of glyoxylate or pyruvate effect considerable stimulation of the activity of isoenzyme-II. The isoenzymes also differ in pH-dependence of activity, kinetic parameters, stability to heat or urea and molecular size. Whereas isoenzyme-I resembles the NADP-linked isocitrate dehydrogenases from other organisms in having a molecular weight under 100000, isoenzyme-II is a much larger enzyme (molecular weight around 300000) resembling the NAD-linked isocitrate dehydrogenases of higher organisms.

THE SEPARATION AND PURIFICATION OF HUMAN LUTEINIZING AND THYROTROPHIC HORMONES

1964 ◽  
Vol 29 (1) ◽  
pp. 61-69 ◽  
Author(s):  
ANNE STOCKELL HARTREE ◽  
W. R. BUTT ◽  
K. E. KIRKHAM
Keyword(s):  
Luteinizing Hormone ◽  
Ion Exchange ◽  
Deae Cellulose ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Separation And Purification ◽  
Hormone Activity ◽  
Human Pituitary ◽  
Thyrotrophic Hormone

SUMMARY Ion-exchange chromatography was used to further purify a human pituitary fraction rich in thyrotrophic and luteinizing hormone activities. Approximately twofold concentration of both activities was obtained by chromatography on IRC-50 at pH 7·5, but the hormones were not separated. Subsequent chromatography on DEAE-cellulose at pH 9·5 led to a tenfold concentration of the luteinizing hormone in a fraction practically free of thyrotrophic activity and to a fourfold concentration of the thyrotrophic hormone in a fraction still exhibiting substantial luteinizing hormone activity.

scholarly journals Persistence of methylated bases in ribonucleic acid of syrian golden hamster liver after administration of dimethylnitrosamine

1979 ◽  
Vol 177 (3) ◽  
pp. 967-973 ◽  
Author(s):  
G P Margison ◽  
J M Margison ◽  
R Montesano
Keyword(s):  
Ribosomal Rna ◽  
Golden Hamster ◽  
Excision Repair ◽  
Experimental System ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Syrian Golden Hamster ◽  
Low Doses ◽  
Enzymic Hydrolysis ◽  
Hydrolysis Of

1. Syrian golden hamster liver ribosomal RNA was isolated up to 96 h after administration of [14C]dimethylnitrosamine at 25 mg/kg or 2.5 mg/kg body weight. 2. The chemical alkyation products, 7-methylguanine, 3-methylcytosine, O6-methylguanosine and 1-methyladenosine, were measured after acidic or enzymic hydrolysis of the RNA to bases or mononucleosides followed by ion-exchange chromatography. 3. Between 7 and 96 h, the relative amounts of alkylation products did not change with time even though the absolute amounts fell by approx. 80% and 51% after the high and low doses respectively. 4. The results suggest that base specific excision repair does not exist for RNA alkylation products in this experimental system.

Analysis of O2′-Methylnucleoside 5′-Phosphates in Snake Venom Hydrolysates of RNA: Identification of O2′-Methyl-5-Carboxymethyluridine as a Constituent of Yeast Transfer RNA

1975 ◽  
Vol 53 (7) ◽  
pp. 735-746 ◽  
Author(s):  
M. W. Gray
Keyword(s):  
Snake Venom ◽  
Deae Cellulose ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Assay Method ◽  
Blocking Group ◽  
Wheat Embryo ◽  
Yeast Trna ◽  
Snake Venom Phosphodiesterase ◽  
Hydrolysis Of

Snake venom phosphodiesterase liberates the O2′-methylnucleoside (Nm) constituents of RNA as the corresponding 5′-nucleotides (pNm), which, in contrast to normal 5′-nucleotides (pN), are resistant to dephosphorylation by venom 5′-nucleotidase. This property provides the basis of a convenient and highly reproducible quantitative assay for Nm residues in RNA. The assay method involves: (1) hydrolysis of RNA with whole or partially-purified snake venom; (2) isolation of the pNm derivatives, as a group, by anion-exchange chromatography on DEAE-cellulose; (3) resolution of the individual pNm compounds by two-dimensional paper chromatography; (4) identification and quantitative measurement of pNm derivatives by ultraviolet absorption spectrophotometry. Using this procedure, the molar proportions of the Nm constituents of wheat embryo, yeast, and Escherichia coli tRNA have been determined. The close correspondence between the values measured by venom hydrolysis and those obtained by analysis of alkali-stable dinucleotide (Nm-Np) sequences attests to the validity of the venom assay, and further indicates that alkali-stable sequences larger than dinucleotides are not present in significant amounts in the tRNA of the above three organisms.During the present investigation, several ultraviolet-absorbing components, not immediately identifiable as ribose-methylated nucleotides, were isolated along with the expected O2′-methylnucleoside 5′-phosphates. Preliminary characterization of one of these compounds suggests that it is a derivative of a novel nucleoside, O2′-methyl-5-carboxymethyluridine (cm5Um). Venom hydrolysis of yeast tRNA liberates the 5′-nucleotide of cm5Um in the form of a carboxyl-blocked derivative (pU-2). During alkaline hydrolysis of yeast tRNA, the blocking group in U-2 is labilized and cm5Um is released as part of an alkali-stable dinucleotide, cm5Um-Ap. The proportion of pU-2 in venom hydrolysates of yeast tRNA (0.02 mol%, the same as the content of cm5Um-Ap in alkaline hydrolysates) suggests that O2′-methyl-5-carboxymethyluridine may be confined to a single isoaccepting species of tRNA in yeast.In an allied study, reinvestigation of the alkali-stable dinucleotide sequences of baker's yeast tRNA has confirmed previous results concerning the sequence distribution of O2′-methylribose in yeast tRNA (Gray, M. W. &Lane, B. G. (1967) Biochim. Biophys. Acta 134, 243–257).

Darstellung und Schwingungsspektren der 35Cl/37Cl-markierten Fluoro-Chloro-Platinate(IV) / Preparation and Vibrational Spectra of 35Cl/37Cl Labelled Fluoro-Chloro-Platinates(IV)

1989 ◽  
Vol 44 (6) ◽  
pp. 619-626 ◽  
Author(s):  
P. Erlhöfer ◽  
W. Preetz
Keyword(s):  
Low Temperature ◽  
Mutual Exclusion ◽  
Deae Cellulose ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Vibrational Modes ◽  
Geometric Isomers ◽  
Deformation Bands ◽  
Isotopic Shifts ◽  
Ir And Raman

All components of the two series Cs2[PtF„35Cl6-n] and Cs2[PtFn37Cl6-n], including the pairs of geometric isomers for n = 2,3, 4, have been prepared and isolated by ion exchange chromatography on DEAE cellulose. The highly resolved low temperature (80 K) IR and Raman spectra of the pure isotopomers show distinctive isotopic shifts for different vibrational modes up to 10 cm-1. The excellent agreement of the observed values with Teller-Redlich calculations verifies the assignment of all stretching and especially of the narrow deformation bands. For transcomplexes containing 35Cl-Pt-37Cl axes, the lowered symmetry affects the restriction of the rule of mutual exclusion

scholarly journals Aspergillus oryzae acid proteinase. Purification and properties, and formation of π-chymotrypsin

1975 ◽  
Vol 147 (1) ◽  
pp. 45-53 ◽  
Author(s):  
R Davidson ◽  
A Gertler ◽  
T Hofmann
Keyword(s):  
Aspergillus Oryzae ◽  
Deae Cellulose ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Molecular Forms ◽  
Acid Proteinase ◽  
Sedimentation Analysis ◽  
Simple Tool ◽  
Purification And Properties ◽  
Yield And Purity

An acid proteinase from Aspergillus oryzae was isolated from a commercial powder by successive (NH4)2SO4 fractionation, acetone precipitation, and ion-exchange chromatography on phosphate- and DEAE-cellulose columns. The purified enzyme was found to be homogeneous by ultracentrifuge-sedimentation analysis (S20, W equal 3.63S), but electrofocusing in polyacrylamide gels and electrophoresis at pH 3.2 revealed that it consists of two very closely migrating bands. No difference in the amino acid composition and enzymic activities of the two partially separated bands could be detected, and it was concluded that the acid proteinase exists in two molecular forms. The enzyme activates bovine trypsinogen and chymotrypsinogen at pH 3.5 (the kappacat. and Km values at 35degrees C are 11.3S- minus 1, 0.10mM and 1.14S- minus 1, 0.18mM respectively). It hydrolyses the Phe-Phe bond of the synthetic pepsin substrates Z-His-Phe-Phe-OEt (kappacat. equal 1.65S- minus 1, Km equal 0.640mM at pH 3.5, 30degrees C) and Z-Ala-Ala-Phe-Phe-OPy4Pr (kappacat. equal 0.37S- minus 1, Km equal 0.037 mM at pH2.9, 39degrees C), where Z represents benzyloxycarbonyl and OPy4Pr represents 3-(4-pyridyl)-propyl 1-ester. Activation of bovine chymotrypsinogen results from the cleavage of the Arg(15)-Ile(16) bond in the zymogen. No other cleavages were observed. The use of A. oryzae proteinase provides a simple tool for the production of pi-chymotrypsin in good yield and purity.

Kristallstruktur von Cs2[B6H5(SCN)]/ Crystal Structure of Cs2[B6H5(SCN)]

1998 ◽  
Vol 53 (8) ◽  
pp. 816-818 ◽  
Author(s):  
W. Preetz ◽  
S. Zander ◽  
C. Bruhn
Keyword(s):  
Crystal Structure ◽  
Ion Exchange ◽  
Structure Determination ◽  
Deae Cellulose ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray

Abstract By reaction of [B6H6]2-with (SCN)2 in dichloromethane at -80 C° the thiocyanatohexaborate anion is formed and can be isolated by ion exchange chromatography on diethylaminoethyl (DEAE) cellulose. The X-ray structure determination of Cs2[B6H5(SCN)] (orthorhombic, space group Pbca with a = 9.506(5), b = 10.644(5), c = 21.857(5) Å, Z = 8) reveals that the SCN substituent is bonded via the S atom with the B-S distance of 1.885(9) Å and the B-S-C angle of 99.8(5)°. The SCN group is nearly linear (179.9(9)°).

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