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1.
Summary We have studied the reactions between adenosine 5-phosphorimidazolide and 9-(2-amino-2-deoxyxylofuranosyl) adenine (I) or 3-methylamino-3-deoxyadenosine (II), both with and without a poly (U) template. We find that both amino compounds react much more rapidly than does adenosine, in the absence of a template. The rate of reaction is greatly enhanced by a poly (U) template in the case of I, but the enhancement is slight in the case of II.Abbreviations A
adenosine
- xylo ANH2
9-(2-amino-2-deoxy--D-xylofuranosyl) adenine
- ANHMe
3-methylamino-3-deoxyadenosine
- ImpA
adenosine 5-phosphorimidazolide
- A3 pA
adenylyl-[35]-adenosine
- A2 pA
adenylyl-[25]-adenosine
- UNPA
adenylyl-[52]-2-amino-2-deoxyuridine
- xylo ANPA
9-[adenylyl-(52)-2-amino-2-deoxy--D-xylofuranosyl]adenine
- A(NMe)pA
adenylyl-[53]-3-methylamino-3-deoxyadenosine
- pA
adenosine 5phosphate
- AppA
P1, P2-diadenosine 5pyrophosphate
- (pA)n
n = 2, 3 [2-5]-linked oligomers of pA
- A2 pA2 pA
[2-5]-linked trinucleoside diphosphate of A
- poly (U)
polyuridylic acid 相似文献
2.
Roots of spinach (Spinacia oleracea L.) seedlings contained only a very low activity of adenosine 5-phosphosulfate sulfotransferase compared to the cotyledons. Adenosine 5-phosphosulfate sulfotransferase activity increased about tenfold in cotyledons during greening. Preparation of organelle fractions from spinach leaves by a combination of differential and isopycnic density gradient centrifugation showed that adenosine 5-phosphosulfate sulfotransferase banded with NADP-glyceraldehyde-3-phosphate dehydrogenase, a marker enzyme for intact chloroplasts. In the fractions of peroxisomes, mitochondria and broken chloroplasts virtually no adenosine 5-phosphosulfate sulfotransferase activity was measured. Comparison with the chloroplast enzyme NADP-glyceraldehyde-3-phosphate dehydrogenase indicates that in spinach, adenosine 5-phosphosulfate sulfotransferase is localized almost exclusively in the chloroplasts.Abbreviations APS
Adenosine 5-phosphosulfate
- APSSTase
Adenosine 5-phosphosulfate sulfotransferase
- BSA
Bovine serum albumin
- BRIJ58
Polyethylene glycolmonostearylether
- DTE
Dithioerythritol
- DTT
Dithiothreitol
- EDTA
Ethylenediaminetetraacetic acid
- ME
2-Mercaptoethanol
- NADP-GPD
NADP-linked glyceraldehyde-3-phosphate dehydrogenase
- PAPS
Adenosine 3-phosphate 5-phosphate 5-phosphosulfate
- POPOP
1,4 Di [2-(5-phenyloxazolyl)]-benzene
- PPO
2,5-Diphenyloxazol
The results presented in this paper are taken from the Ph. D. thesis of H.F. 相似文献
3.
Summary Short oligocytidylates can act as templates for the self-condensation of guanosine 5-phosphorimidazolide. In the absence of a catalytic metal ion or in the presence of Pb2+ a noticeable template effect is already observed with the dimer and the yield of long oligomers reaches a plateau with a hexamer template. Short templates give oligomers longers than the template length. The products are predominantly 2-5 linked for the Pb2+-catalyzed reaction while mixed linkages are observed in the uncatalyzed reaction.In the presence of Zn2+, a template effect is first observed with the pentamer and is maximal by the heptamer. The products are predominantly 3-5 linked. Oligomers shorter than or as long as the template are obtained in substantial yield, and longer products in much lower yields.Abbreviations G
Guanosine
- Gp
guanosine 2(3)-phosphate
- pG
guanosine 5-phosphate
- Gp!
guanosine cyclic 2,3-phosphate
- ImpG
guanosine 5-phosphorimidazolide
- ImpG*
[8-14C]-guanosine 5-phosphorimidazolide
- pGp
5-phosphoguanosine 2(3)-phosphate
- G2pG
guanylyl-[2-5]-guanosine
- G3pG
guanylyl-[3-5]-guanosine
- ImpGpG
5-phosphorimidazolide of GpG
- (pG)n (n = 2,3)
oligomers of pG
- GppG
P1, P2-diguanosine 5-diphosphate
- GppGpG
5-[guanosine 5-pyrophosphate] of GpG
- NH2pG
guanosine 5-phosphoramidate
- (pG)4+
tetramer and higher oligoguanylates with 5 terminal phosphate
- oligo(G)
oligoguanylate
- Cp
cytidine 2(3)-phosphate
- Cp!
cytidine cyclic 2,3-phosphate
- (Cp)n–1 Cp! (n= 2,3,4)
oligocytidylates terminated by 5-OH groups and 2,3-cyclic phosphates
- oligo(C)
oligocytidylate
- poly(C)
polycytidylic acid
- poly(U)
polyuridylic acid
- poly(C,G)
random copolymer of C and G
- BAP
bacterial alkaline phosphatase (E. coli)
- EDTA
ethylenediaminetetraacetic acid
- Rf
chromatographic mobility 相似文献
4.
5.
The action of cyclic adenosine-3,5-monophosphate (3,5-AMP) and of substances modifying the rate of its breakdown (inhibitors and activators of phosphodiesterase) on the olfactory epithelium was investigated in frogs. The slow electrical response of the olfactory epithelium to stimulation by solutions of various substances was recorded. Cyclic 3,5-AMP and its dibutyryl derivative were found to excite the olfactory receptors effectively. Responses to these substances developed after an appreciably longer delay than responses to stimulation by solutions of odiferous substances. It is postulated that the depolarizing action of 3,5-AMP and dibutyryl 3,5-AMP is manifested only after they have penetrated inside the receptor cell through its membrane. Both 5-AMP and cyclic 2,3-AMP were ineffective. In the next series of experiments the integral receptor potential was recorded in response to short stimulation by the vapor of an odiferous substance. The duration of this potential was increased after treatment of the olfactory epithelium with phosphodiesterase inhibitors: methylxanthines or papaverine. Conversely, the negative wave of the integral receptor potential was shortened under the influence of the phosphodiesterase activator imidazole. Cyclic 3,5-AMP is considered to play the role of mediator in the mechanism of excitation of the olfactory receptor; during interaction between an odiferous substance and the receptor, adenyl cyclase is activated and the concentration of 3,5-AMP increases; this, in turn, causes depolarization of the receptor cell membrane.Institute of Chemical Physics, Academy of Sciences of the USSR, Moscow. Translated from Neirofiziologiya, Vol. 5, No. 4, pp. 415–422, July–August, 1973. 相似文献
6.
Rachel Galun 《Entomologia Experimentalis et Applicata》1989,50(2):133-139
Females of the medfly, Ceratitis capitata, prefer sucrose solutions containing ribonucleotides to sucrose solutions without them. The order of preference for the nucleotides was: 5GMP>GTP>5CMP>5IMP >dGMP>5UMP>5AMP>5XMP=ATP=2 & 3GMP=RP>3AMP.2AMP, guanosine, inosine, adenine and 5TMP produced no significant stimulation. Females sterilized by irradiation showed reduced attraction to 5GMP as compared to non-irradiated females.Optimal molecular configuration for phagostimulation includes: phosphorylation at the 5 position of the ribose, free hydroxyl groups at 2 and 3 on the ribose, and an NH2 group at the 2 position of the aromatic ring of purine.It is proposed that the 5GMP in yeast hydrolyzate can be used as a measure of the suitability of the hydrolyzate as a bait.
Abbreviations 5AMP Adenosine 5-monophosphate - 3AMP Adenosine 3-monophosphate - 2AMP Adenosine 2-monophosphate - dAMP 2-deoxyadenosine 5-monophosphate - ADP Adenosine 5-diphosphate - ATP Adenosine 5-triphosphate - 5GMP Guanosine 5-monophosphate - 2GMP Guanosine 2-monophosphate - 3GMP Guanosine 3-monophosphate - dGMP 2-deoxyguanosine 5-monophosphate - GDP Guanosine 5-diphosphate - GTP Guanosine 5-triphosphate - 5IMP Inosine 5-monophosphate - IDP Inosine 5-diphosphate - ITP Inosine 5-triphosphate - 5XMP Xanthosine 5-monophosphate - 5CMP Cytidine 5-monophosphate - dCMP 2 deoxycytidine 5-monophosphate - CTP Cytidine 5-triphosphate - 5UMP Uridine 5-monophosphate - 5TMP Thymidine 5-monophosphate - RP Ribose 5 monophosphate 相似文献
Résumé La femelle de la mouche méditerranéenne des fruits, Ceratitis capitata, préfère les solutions de sucrose contenant des ribonucléotides aux simples solutions de sucrose. Lórdre de préférence pour les nucléotides est le suivant: 5GMP>GTP>5CMP>5IMP >dGMP>5UMP>5AMP>5XMP=ATP =2 & 3GMP=RP>3AMP.Le 2AMP, la guanosine, l'inosine, l'adénine et le 5TMP provoquent une stimulation significative. Les femelles montrent aprés stérilisation par irradiation une attirance réduite pour le 5GMP par comparaison avec les femelles non-irradiées.La configuration moléculaire optimale pour la phagostimulation comprend: la phosphorylation en position 5 du ribose; des groupes hydroxyles libres en 2 et 3 sur le ribose; et un groupe NH2 en position 2 sur le noyau aromatique.Nous proposons que le 5GMP dans l'hydrolysat de levure puisse être utilisé pour mesurer la capacité de l'hydrolysat comme appât.
Abbreviations 5AMP Adenosine 5-monophosphate - 3AMP Adenosine 3-monophosphate - 2AMP Adenosine 2-monophosphate - dAMP 2-deoxyadenosine 5-monophosphate - ADP Adenosine 5-diphosphate - ATP Adenosine 5-triphosphate - 5GMP Guanosine 5-monophosphate - 2GMP Guanosine 2-monophosphate - 3GMP Guanosine 3-monophosphate - dGMP 2-deoxyguanosine 5-monophosphate - GDP Guanosine 5-diphosphate - GTP Guanosine 5-triphosphate - 5IMP Inosine 5-monophosphate - IDP Inosine 5-diphosphate - ITP Inosine 5-triphosphate - 5XMP Xanthosine 5-monophosphate - 5CMP Cytidine 5-monophosphate - dCMP 2 deoxycytidine 5-monophosphate - CTP Cytidine 5-triphosphate - 5UMP Uridine 5-monophosphate - 5TMP Thymidine 5-monophosphate - RP Ribose 5 monophosphate 相似文献
7.
Summary 2-Amino-2-deoxyuridine reacts efficiently with nucleoside 5-phosphorimidazolides in aqueous solution. The dinucleoside monophosphate analogues were obtained in yields exceeding 80% under conditions in which little reaction occurs with the natural nucleosides.In a similar way, the 5-phosphorimidazolide of 2-amino-2-deoxyuridine undergoes self-condensation in aqueous solution to give a complex mixture of oligomers.The phosphoramidate bond in the dinucleoside monophosphate analogues is stable for several days at room temperature and pH 7. The mechanisms of their hydrolysis under acidic and alkaline conditions are described.Abbreviations A
adenosine
- C
cytidine
- G
guanosine
- U
uridine
- T
thymidine
- UN
3
2-azido-2-deoxyuridine
- UNH
2
2-amino-2-deoxyuridine
- ImpA
adenosine 5-phosphorimidazolide
- ImpU
uridine 5-phosphorimidazolide
- ImpUN
3
2-azido-2-deoxyuridine 5-phosphorimidazolide
- ImpUNH
2
2-amino-2-deoxyuridine 5-phosphorimidazolide
- pA
adenosine 5-phosphate
- pU
uridine 5-phosphate
- pUN
3
2-azido-2-deoxyuridine 5-phosphate
- pUNH
2
2-amino-2-deoxyuridine 5-phosphate
- UpA
uridylyl-[35]-adenosine
- UpU
uridylyl-[35]-uridine
- UNpA
adenylyl-[52]-2-amino-2-deoxy-uridine
- UNpU
uridylyl-[52]-2-amino-2-deoxyuridine (pUN)n n=2,3,4 [25]-linked oligomers of pUNH
2 poly(A) polyadenylic acid
- Im
imidazole
- MeIm
l-methylimidazole 相似文献
8.
James P. Ferris Gözen Ertem Vipin Agarwal 《Origins of life and evolution of the biosphere》1989,19(2):165-178
The reaction of the 5-AMP with water soluble carbodiimide (EDAC) in the presence of Na+-montmorillonite 22A results in the formation of 2,5-(pA)2 (18.9%), 3,5-(pA)2 (11%), and AppA (4.8%). When poly(U) is used in place of the clay the product yields are 2,5-(pA)2 (15.5%), 3,5-(pA)2 (3.7%) and AppA (14.9%). The 3,5-cyclic dinucleotide, 3,5-c(pA)2, is also formed when poly(U) is used. AppA is the principal reaction product when neither clay nor poly(U) is present in the reaction mixture. Products which contain the phophodiester bond are formed at different ionic strengths, pH and temperatures using Na+-montmorillonite. Phosphodiester bond formation was not observed when Cu2+-montmorillonite was used or when DISN was used in the place of EDAC. The extent catalysis of phophodiester bond formation varied with the particular clay mineral used. Those Na+-clays which bind 5-AMP more strongly are better catalysts. Cu2+-montmorillonite, which binds 5-AMP strongly, exhibits no catalytic activity. 相似文献
9.
Ahlert Schmidt 《Archives of microbiology》1977,112(3):263-270
Crude extracts of Rhodospirillum rubrum catalyzed the formation of acid-volatile radioactivity from (35S) sulfate, (35S) adenosine-5-phosphosulfate, and (35S) 3-phosphoadenosine-5-phosphosulfate. An enzyme fraction similar to APS-sulfotransferases from plant sources was purified 228-fold from Rhodospirillum rubrum. It is suggested here that this enzyme is specific for adenosine-5-phosphosulfate, because the purified enzyme fraction metabolized adenosine-5-phosphosulfate, however, only at a rate of 1/10 of that with adenosine-5-phosphosulfate. Further, the reaction with 3-phosphoadenosine-5-phosphosulfate was inhibited with 3-phosphoadenosine-5-phosphate whereas this nucleotide had no effect on the reaction with adenosine-5-phosphosulfate. For this activity with adenosine-5-phosphosulfate the name APS-sulfotransferase is suggested. This APS-sulfotransferase needs thiols for activity; good rates were obtained with either dithioerythritol or reduced glutathione; other thiols like cysteine, 2-3-dimercaptopropanol or mercaptoethanol are less effective. The electron donor methylviologen did not catalyze this reaction. The pH-optimum was about 9.0; the apparent K
m for adenosine-5-phosphosulfate was determined to be 0.05 mM with this so far purified enzyme fraction. Enzyme activity was increased with K2SO4 and Na2SO4 and was inhibited by 5-AMP. These properties are similar to assimilatory APS-sulfotransferases from spinach and Chlorella.Abbreviations APS
adenosine-5-phosphosulfate
- PAPS
3-phosphoadenosine-5-phosphosulfate
- 5-AMP
adenosine-5-monophosphate
- 3-AMP
adenosine-3-monophosphate
- 3-5-ADP
3-phosphoadenosine-5-phosphate (PAP)
- DTE
dithiorythritol
- GSH
reduced glutathione
- BAL
2-3-dimercaptopropanol 相似文献
10.
Hiroaki Sawai 《Journal of molecular evolution》1981,17(1):48-51
Summary Oligouridylates with more than eight chain units can serve as a template for the template-directed condensation of ImpA catalyzed by Pb2+ ion. The templates and the Pb2+ ion catalyst facilitate the formation of longer oligoadenylates with five or more units. The ratio of 3–5 linked oligomers to the 2–5 isomers increases with increasing chain length of the oligouridylate template. Short oligouridylates up to a hexamer tend to decrease the yield of oligoadenylates, and do not affect the selectivity of internucleotide linkage.Abbreviations EDTA
ethylenediaminetetracetic acid
- Tris
tris(hydroxymethyl)aminomethane
- A
adenosine
- ImpA
adenosine 5-phosphorimidazolide
- pA
adenosine 5-phosphate
- Ap
adenosine 2(3)-phosphate
- poly A
polyadenylic acid
- AppA
P1,P2-diadenosine 5-diphosphate
- pAp
adenosine 2(3),5-diphosphate
- ApA
adenylyl adenosine
- (pA)n (n = 2,3,)
oligomers of pA
- ImpApA
5-phosphorimidazolide of ApA
- U
uridine
- pU
uridine 5-phosphate
- Up
uridine 2(3)-phosphate
- poly U
polyuridylic acid
- pUp
uridine 2(3),5-diphosphate
- (pU)n (n = 2,3,)
oligomers of pU
- (pU)n – (pA)m
cooligomers composed of (pU)n and (pA)m units
- AppUpUpUpUp
pyrophosphate derived from pA and (pU)4
- AppUp
P1-(adenosine 5)-P2-(uridine 2(3)-phosphate 5) -pyrophosphate
- BAP
bacterial alkaline phosphatase
- VPD
venom phosphodiesterase
- N.P1
nuclease P1
- RNase A
pancreatic ribonuclease
- A*
radioactive adenosine 相似文献
11.
Summary Nucleoside-5-triphosphates such as 5-ATP and 5-GTP can be produced efficiently and continuously from 3-mononucleotides such as 3-AMP and 3-GMP by a series of processes consisting of two reaction phases using dried cells of Candida sp. N-25-2 (a hydrocarbon assimilating yeast). Moreover, incidentally to the 5-triphosphates, free uracil is yielded almost stoichiometrically from 3-CMP and 3-UMP which, as is well known, are main concomitant products depolymerized from RNA. Uracil is then also available for many usage. 相似文献
12.
Summary 1. The ribonuclease activity in sections from freeze-dried Carnoy-fixed rat pancreas has been characterized through studies on the products of interaction with synthetic nucleoside derivatives, nucleotide esters, and of the polynucleotide synthetic properties.2. Homogenates of the sections in McIlvaine's buffer atph 7.0 degrade pyrimidine 2:3-phosphates to the corresponding 3-dihydrogen phosphate, and the purine derivatives at a much slower rate.3. Synthetic cytidylyl-cytidine, and benzyl- and ethyl-3-esters of pyrimidine nucleotides are degraded to nucleoside 3-phosphates. All the purine, and the 2-esters of pyrimidine nucleotides are not affected during 24 hours of incubation.4. Under influence of the homogenates, ribopolynucleotides will readily be synthesized from cytidine-2:3-phosphate and cytidine, the 3-P-5dinucleotide links being identified in cytidylyl-cytidine and cyclic dicytidylic acid.5. The conclusion is reached that the activity of the sections coincides with the DEase and CPase activity of crystalline pancreatic RNase. Some aspects of the possibilities for the histochemical localization of the activity are briefly discussed.With 6 Figures in the TextAided by grants from the Royal Physiographic Society of Lund, the Nora Sörensson Foundation, and the J. V. and Charlotta Lundgren Foundation. 相似文献
13.
Summary The self-condensation of 2(3)-O-glycyl esters of adenosine, adenosine-5-(O-methylphosphate) and P1, P2-diadenosine-5-pyrophosphate in 6.2 mM solutions at pH 8.0 and -5°C in the presence of 12.5 mM poly(U) yields approximately 3 times as much diketopiperazine as reactions without poly(U). As the concentration of 2(3)-O-(glycyl)-P1, P2-diadenosine-5-pyrophosphate is decreased from 6.2 mM to 1.5 mM the yield of diketopiperazine in the presence of poly(U) decreases slightly from 6.6% to 5.2%, whereas, in the absence of poly(U) the yield of diketopiperazine decreases substantially from 2.4% to 0.75%. The enhanced yield of diketopiperazine that is attributed to the template action of poly(U) is temperature dependent and is observed only at temperatures below 10°C (5°C to -5°C) for 6.2 mM 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate) and below 23°C (15°C to -5°C) for 6.2 mM 2(3)-O-(glycyl)-P1, P2-diadenosine-5-pyrophosphate. The absence of a template effect at high temperatures is attributed to the melting of the organized helices. The hydrolysis half-lives at pH 8.0 and -5°C of 2(3)-O-(glycyl)-adenosine, 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate), 2(3)-O-(glycyl)-P1, P2-diadenosine-5-pyrophosphate, and 5-O-(glycyl)-adenosine in the presence of poly(U) are substantially larger than their half-lives in the absence of poly(U). The condensation of 2(3)-O-(glycyl)-adenosine yields 5% of 5-O-(glycyl)-adenosine in the presence of poly(U) compared to 0.7% in the absence of poly(U).Abbreviations DKP
diketopiperazine
- (gly)2
glycylglycine
- (gly)3
glycylglycylglycine
- AppA-gly
2(3)-O-(glycyl)-P1, P2-diadenosine-5-pyrophosphate
- MepA-gly
2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate)
- Ado-2(3)-gly
2(3)-O-(glycyl)-adenosine
- Ado-5-gly
5-O-(glycyl)-adenosine
- Boc-gly
N-tert-butyloxycarbonylglycine
- AppA
P1, P2-diadenosine-5-pyrophosphate
- MepA
adenosine-5-(O-methylphosphate)
- AppA-Boc-gly
2(3)-O-(Boc-glycyl)-P1, P2-diadenosine-5-pyrophosphate
- Ado-5-Boc-gly
5-O-(Boc-glycyl)-adenosine
- Ado-2(3)-Boc-gly
2(3)-O-(Boc-glycyl)-adenosine 相似文献
14.
W. O. Abel W. Knebel H. -U. Koop J. R. Marienfeld H. Quader R. Reski E. Schnepf B. Spörlein 《Protoplasma》1989,152(1):1-13
Summary An X-ray induced mutant (PC22) of the moss,Physcomitrella patens was analysed with respect to its morphology, physiology and suitability for microculture techniques. The mutant protonemata are defective in bud formation and in chloroplast division. As a consequence of the latter, giant chloroplasts are formed which disturb the development of the phragmoplast, the formation of regular cross walls, and cell division. Abnormal cross walls are rich in callose. The actin cytoskeleton was found to be less regularly developed in the mutant than in the wild type. Three-dimensional analysis of the microtubular arrangement with confocal laser scan microscopy demonstrates a close association between spindle- or phragmoplast- and interphase-microtubules. The deficiencies in chloroplast division and in bud formation can partly be compensated for by exogeneously applied cytokinin. The suitability of this particular developmental mutant for further studies was shown by regeneration of protoplasts in microculture and microinjection of the fluorochrome Lucifer yellow into the chloroplast.Abbreviations CLSM
confocal laser scan microscope
- DAPI
diamidinophenyl indole
- DiOC
3,3-dihexyloxacarbocyanine iodide
- EGTA
ethylene glycol-bis-(-amino-ethylether-N,N,N,N-tetraacetic acid
- i6Ade
N6-(2-isopentenyladenine)
- PIPES
piperazine-N, N-bis-2-ethanesulfonic acid
- ptDNA
chloroplast DNA
Devoted to the memory of Prof. Dr. O. Kiermayer, our colleague and friend. 相似文献
15.
Summary We have synthesized 2(3)-O-(glycyl)-adenosine-5-(O-methylphos-phate), an analogue of the 3-terminus of aminoacylated tRNA. A 0.4M solution of this compound maintained at pH 8.2, yields 5.5% of diglycine and 11.5% of diketopiperazine, in addition to the hydrolysis products glycine and adenosine-5-(O-methylphosphate). Under the same conditions, glycine ethyl ester reacts much more slowly, but ultimately gives similar yields of diglycine and diketopiperazine.The aminolysis of 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate) by free glycine is relatively inefficient, but serine reacts 20 times more rapidly and yields up to 50% of N-glycylserine. The prebiotic significance of these reactions is discussed.Abbreviations MepA
adenosine-5-(O-methylphosphate)
- MepA-gly
2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate)
- MepA-bis-gly
2,3-O-(bis-glycyl)-adenosine-5-(O-methylphosphate)
- DKP
diketopiperazine
- gly Et
glycine ethyl ester
- gly-ser
N-glycylserine
- O-gly-ser
O-glycylserine
- O-(gly)-gly-ser
O-(glycyl)-glycylserine
- Boc-gly
N-tert-butyloxycarbonylglycine
- MepA-Boc-gly
2(3)-O-(Boc-glycyl)-adenosine-5-(O-methylphosphate)
- MepA-bis-Boc-gly
2,3-O-(bis-Boc-glycyl)-adenosine-5(O-methylphosphate)
- (gly)2
diglycine
- (gly)3
triglycine 相似文献
16.
Summary Evaporation of a solution of thymidine plus either theexo or theendo diastereomer of uridine cyclic 2,3-O, O-phosphorothioate (U > p(S) in 1,2-diaminoethane hydrochloride buffer gave the 2,5 and 3,5 isomers of (P-thio) uridylylthymidine (Up(S)dT) in a ratio of 1:2 with a combined yield of about 20%. These isomers were re-converted to U > p(S) and dT by a reaction that is known to proceed by an in-line mechanism. Both the 2,5 and 3,5 isomers gave as product the same diastereomer of U > p(S) that had been used originally in their formation. These dry-state prebiotic reactions (Verlander, Lohrmann, and Orgel 1973) are thus shown to be stereospecific, and both the 2,5 and 3,5 internucleotide bonds are formed by an in-line mechanism.Abbreviations DAE
1,2-diaminoethane
- HPLC
high pressure liquid chromatography
- RNase
bovine pancreatic ribonuclease A, EC 3.1.4.22
- TEAB
triethylammonium bicarbonate
- tris
tris(hydroxymethyl)aminomethane
- UMP(S)
uridine monophosphorothioate
- U > p
uridine cyclic 2,3-phosphate
- U > p(S)
uridine cyclic 2,3-O, O-phosphorothioate
- Up(S)dT
(P-thio)uridylylthymidine
- U2p(Rp-S)5dT
(P-thio)uridylylthymidine with theR configuration at phosphorous, and a 2,5 internucleotide linkage 相似文献
17.
P. N. Marshall 《The Histochemical journal》1976,8(5):487-499
Synopsis Commercial samples of Erythrosin B (CI 45430), Erythrosin Y (CI 45425), Fluorescein (CI 45350), Phloxine (CI 45410) and Rose Bengal (CI 45440) have been analysed by thin-layer chromatography. The Erythrosins were found to be mixtures consisting in the main of 4-iodofluorescein, 4,5-di-iodofluorescein, 2,4,5-triiodofluorescein and 2,4,5,7-tetraiodofluorescein, in some instances together with 2,4,5-tri-iodo-4,5,6,7-tetrachlorofluorescein and 2,4,5,7-tetraiodo-4,5,6,7-tetrachlorofluorescein. Samples of Fluorescein were mixtures of the nominal dye usually with traces of several unidentified, fluorescent components. Those of Phloxine consisted mainly of mixtures of 4-bromo-4,5,6,7-tetrachlorofluorescein, 4,5-dibromo-4,5,6,7-tetrachlorofluorescein, 2,4,5-tribromo-4,5,6,7-tetrachlorofluorescein and 2,4,5,7-tetrabromo-4,5,6,7-tetrachlorofluorescein, often with 4,5,6,7-tetrachlorofluorescein Samples of Rose Bengal were mixtures of 4-iodo-4,5,6,7-tetrachlorofluorescein, 4,5-di-iodo-4,5,6,7-tetrachlorofluorescein, 2,4,5-tri-iodo-4,5,6,7-tetrachlorofluorescein and 2,4,5,7-tetraiodo-4,5,6,7-tetrachlorofluorescein together with some unidentified components.Most of the commercial dye samples gave an insoluble residue when extracted with methanol. This residue was usually inorganic carbonate or halide. Some possible practical consequences of the various impurities are discussed. 相似文献
18.
Kojima C Kawashima E Sekine T Ishido Y Ono A Kainosho M Kyogoku Y 《Journal of biomolecular NMR》2001,19(1):19-31
The sugar conformation of a DNA decamer was studied with proton-proton 3J coupling constants. Two samples, one comprising stereospecifically labeled 2-R-2H for all residues and the other 2-S-2H, were prepared by the method of Kawashima et al. [J. Org. Chem. (1995) 60, 6980–6986; Nucleosides Nucleotides (1995) 14, 333–336], the deuterium labeling being highly stereospecific 99% for all 2-2H, 98% for 2-2H of A, C, and T, and 93% for 2-2H of G). The 3J values of all H1-H2 and H1-H2 pairs, and several H2-H3 and H2-H3 pairs were determined by line fitting of 1D spectra with 0.1–0.2 Hz precision. The observed J coupling constants were explained by the rigid sugar conformation model, and the sugar conformations were found to be between C3-exo and C2-endo with m values of 26° to 44°, except for the second and 3 terminal residues C2 and C10. For the C2 and C10 residues, the lower fraction of S-type conformation was estimated from JH1H2 and JH1H2 values. For C10, the N–S two-site jump model or Gaussian distribution of the torsion angle model could explain the observed J values, and 68% S-type conformation or C1-exo conformation with 27° distribution was obtained, respectively. The differences between these two motional models are discussed based on a simple simulation of J-coupling constants. 相似文献
19.
S. V. Vasil'eva T. V. Abramova T. M. Ivanova G. V. Shishkin V. N. Sil'nikov 《Russian Journal of Bioorganic Chemistry》2004,30(3):234-242
A convenient preparative synthesis of 2-amino-2-deoxyuridine was developed. Starting from 2-amino-2-deoxyuridine and 2-amino-2-deoxycytidine, monomers for the phosphoamidite oligonucleotide synthesis were obtained that carry a linker with methoxyoxalamide groups in position 2. 相似文献
20.
To evaluate the effects of midazolam on the angiokinesis of segments of rabbits' thoracic aorta stripped of endothelium and stimulated by adrenaline.Two groups of aortic rings removed from albinic rabbits anesthetized with thiopental were used (Group I – 6 animals; Group II – 12 animals), stripped of endothelium, studied in an organ chamber, perfused by Krebs-Henseleit solution. The groups were stimulated by adrenaline, recording the maximum contraction and dT/dt at 12, 36, 60 and 120. When the plateau phase was reached, the vessel was washed with perfusion solution, recording relaxation at 2, 4 and 6. When the base values were reached, Group I underwent a new adrenergic stimulus; and Group II was stimulated with midazolam and then with adrenaline, and the same values were recorded. T test was applied as a statistical analysis when two variables were studied. When studying more than two variables the Anova test was used, supplemented by the Tuckey test.Group I did not show any significant difference between the two stimuli. Group II – the midazolam significantly reduced the maximum contraction induced by adrenaline (83.01 ± 4.11%) (p < 0.01). The dT/dt was reduced at 12 (57.06 ± 8.47%), and also at 36 (70.59 ± 5.26%). There was no significance at 60 and 120 (p < 0.01).The relaxation increased significantly at all measurements – at 2-adrenaline 39.31 ± 9.60%; adrenaline/midazolam: 44.06 ± 9.62% (p < 0.05). At 4-adrenaline: 53.08 ± 8.3%; adrenaline/midazolam: 61.68 ± 8.50% (p < 0.01). At 6-adrenaline: 76.26 ± 5.45%; adrenaline/midazolam: 84.20 ± 7.96% (p < 0.01).Midazolam significantly reduced the maximum contraction obtained by the adrenergic stimulus as well as the dT/dt in the initial phases of contraction. The relaxation speed also increased. 相似文献