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1.
Takemitsu Mizunaga 《Bioscience, biotechnology, and biochemistry》2013,77(9):2021-2027
The regulation of acid phosphatase synthesis by various phosphate compounds was examined in Baker’s yeast protoplasts. Synthesis was repressed by inorganic phosphate and phosphomonoesters. Phosphomonoesters were hydrolysed by a small amount of non-specific acid phosphatase present in the protoplast membrane. The inorganic phosphate that was liberated and incorporated into protoplasts probably repressed acid phosphatase synthesis. Phosphodiesters, such as 3′, 5′-cyclic AMP, 3′, 5′-cyclic CMP and 3′, 5′-cyclic GMP, promoted acid phosphatase synthesis. The effect of 3′, 5′-cyclic AMP was not to overcome hexose repression, because high hexose did not repress acid phosphatase synthesis. 3′, 5′-cyclic AMP did not overcome repression of the enzyme synthesis by inorganic phosphate. From these observations 3′, 5′-cyclic nucleotides probably had some effect on the yeast acid phosphatase-synthesizing system but the exact role of the nucleotides is obscure. 相似文献
2.
Penny E. Diffley Alan Geisbrecht Russell P. Newton Michael Oliver Christopher J. Smith Judith Vaughan 《Plant biosystems》2013,147(2):143-156
ABSTRACT Fast-atom bombardment mass spectrometry (FABMS), and collisionally-induced dissociation and mass-analyzed ion kinetic energy spectrum scanning (CID/MIKES) have been used to examine cation effects on a Phaseolus chloroplast complex phosphodiesterase activity. The kinetic parameters of the activity, and the effects of Li+, Na+, K+, Mg2+, Mn2+ and Fe3+ upon them, were determined with 3′,5′-cyclic AMP, -GMP and -CMP, and 2′,3′-cyclic AMP, -GMP and -CMP as substrates. Irrespective of the presence of cations and of the complex nucleotidase, the preferred substrate is a 3′,5′-cyclic nucleotide, not a 2′,3′-cyclic nucleotide. In the presence of the nucleotidase 3′,5′-cyclic AMP and 3′,5′-cyclic GMP are the best substrates, unless Fe3+ ions are present. Mg2+ and Mn2+ stimulate hydrolysis of 3′,5′-cyclic AMP and 3′,5′-cyclic GMP by the complex. However, Fe3+ inhibits these activities but stimulates the hydrolysis of 3′,5′-cyclic CMP. Kinetic data indicate that each of these six substrates is hydrolyzed at a single, common, catalytic site. Differentiation of the phosphodiesterase isomeric mononucleotide products by FABMS CID/MIKES analysis indicates that in the absence of ions and after removal of the nucleotidase, the 3′-ester linkage of the 3′,5′-cyclic substrates was hydrolyzed exclusively. Addition of monovalent and divalent ions results in hydrolysis of both the 5′- and 3′-ester linkages. 相似文献
3.
《Experimental mycology》1984,8(4):334-341
The ascomyceteSaccobolus platensis Gamundi´& Ranalli requires light to produce apothecia. It has now been found that this light requirement can be satisfied by a 24-h pulse of white light at certain stages of the sexual cycle. The addition of exogenousN6,O2′-dibutyryl adenosine 3′,5′-cyclic monophosphate (db-cyclic AMP) to the dark growing mycelia could replace rather efficiently the inductory effect of light; cyclic AMP,N6-monobutyryl cyclic AMP, andO2′-monobutyryl cyclic AMP were less effective, while guanosine 3′,5′-cyclic monophosphate (cyclic GMP) was a very weak inducer. An inducing effect similar to that of db-cyclic AMP was obtained by the addition of 3-isobutyl-1-methylxanthine (MIX) or theophylline to cultures developing in darkness. In the presence of theophylline, endogenous cyclic AMP levels of dark-grown mycelia were several fold higher than those of control cultures. The cyclic AMP content of mycelia growing under different light regimes was measured and no significant differences were observed. However, cultures submitted to white light showed an increase in adenylate cyclase (ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1) and a decrease in cyclic AMP phosphodiesterase (3′,5′-cyclic AMP 5′-nucleotidohydrolase, EC 3.1.4.17) specific activities compared with the activities of dark-grown mycelia. The cyclic AMP phosphodiesterase activity was strongly inhibited by theophylline and by MIX. The possible role of cyclic AMP in the induction of apothecia in this species is discussed. 相似文献
4.
《Bioscience, biotechnology, and biochemistry》2013,77(7):1276-1280
An enzyme that catalyzed the deamination of adenosine 3′-phenylphosphonate was purified from squid liver to homogeneity as judged by SDS-PAGE. The molecular weight of the enzyme was estimated to be 60,000 by SDS-PAGE and 140,000 by Sephadex G-150 gel filtration. The enzyme deaminated adenosine, 2′-deoxyadenosine, 3′-AMP, and 2′,3′-cyclic AMP, but not adenine, 5′-AMP, 3′,5′-cyclic AMP, ADP, or ATP. The apparent Km and Vmax at pH 4.0 for these substrates were comparable (0.11-0.34mM and 179-295 μmol min?1 mg?1, respectively). The enzyme had maximum activity at pH 3.5-4.0 for adenosine 3′-phenylphosphonate, at pH 5.5 for adenosine and 2′-deoxyadenosine, and at pH 4.0 for 2′,3′-cyclic AMP and 3′-AMP when the compounds were at concentration of 0.1 mM. The Km at 4.0 and 5.5 for each substrate varied, but the Vmax were invariant. These results indicated that the squid enzyme was a novel adenosine (phosphate) deaminase with a unique substrate specificity. 相似文献
5.
Glucagon was found to activate the low Km form of 3′,5′-cyclic AMP phosphodiesterase in intact isolated rat hepatocytes while the high Km phosphodiesterase was unaltered. Activation was concentration dependent and occurred at the same concentration required to observe an increase in 3′,5′-cyclic AMP levels in the cell. The maximal increase in activity occurred within 5 minutes of incubation with glucagon and was sustained for the 35 minutes assayed. 相似文献
6.
A new continuous spectrophotometric method for determining 2′,3′-cyclic nucleotide 3′-phosphohydrolase (EC 3.1.4.37) is described. The assay method involves monitoring the decrease in pH which accompanies the hydrolysis of 2′,3′-cyclic AMP. The reaction is performed in the presence of phenol red and the pH change is followed spectrophotometrically by recording the decrease in absorbance of the basic chromophore at 560 nm. The assay method is sufficiently sensitive to make accurate determinations of CNPase activity in 20-μl samples of CNS homogenates containing less than 5 μg protein. The primary advantage of the phenol red CNPase assay is the ease and speed with which it is performed. 相似文献
7.
Flagellation and β-galactosidase activity were repressed in electron transport-deficient mutants of Escherichia coli K-12. The repressed state was alleviated upon restoring respiration capacity or in the presence of added 3′,5′-cyclic AMP. The repressed/derepressed states observed with varying respiration rates were due to modulation of the intracellular 3′,5′-cyclic AMP content effected by respective changes in the activity of adenylate cyclase as a function of respiration rate. 相似文献
8.
9.
Sei-ichi Tanuma Takehiro Arita Kohtaro Kawashima Hiroyoshi Endo 《Biochemical and biophysical research communications》1982,104(2):483-490
Poly(ADP-ribose) glycohydrolase was found in metaphase chromosomes of HeLa S3 cells. Adenosine diphosphate ribose and 3′, 5′-cyclic AMP inhibited the glycohydrolase activity, whereas ADP, ATP, NAD and 3′,5′-cyclic GMP did not. The hydrolytic product of poly(ADP-ribose) bound to metaphase chromosomes with this enzyme was identified as adenosine diphosphate ribose. 相似文献
10.
C Soler-Argilaga R L Russell M Heimberg 《Biochemical and biophysical research communications》1977,74(4):1340-1347
Livers from fed male rats were perfused with O2′-monobutyryl guanosine 3′,5′-cyclic monophosphate. The output of triglyceride was reduced, while output of ketone bodies and glucose was stimulated by 10?4M monobutyryl guanosine 3′,5′-cyclic monophosphate. No effect was observed with 10?5 M nucleotide. Monobutyryl guanosine 3′,5′-cyclic monophosphate did not affect uptake of free fatty acids. In these respects, monobutyryl guanosine 3′,5′-cyclic monophosphate mimics the effects of dibutyryl adenosine 3′,5′-cyclic monophosphate, although the guanylic nucleotide seems to be less potent than the adenosine 3′,5′-cyclic monophosphate derivative. 相似文献
11.
Cyclic AMP-induced tyrosinase synthesis in Neurospora crassa 总被引:6,自引:0,他引:6
Cyclic AMP induces the synthesis of tyrosinase in . Adenine, adenosine, 3′-AMP, 5′-AMP, and 2′,3′-cyclic AMP have no inductive effect while 8-bromocyclic AMP and dibutyryl cyclic AMP are good inducers. Caffeine and theophylline, inhibitors of cyclic AMP phosphodiesterase, also induce tyrosinase. A possible relationship between cyclic AMP induction and previously reported induction by cycloheximide is suggested. 相似文献
12.
Partially purified nucleotide fraction of moss containing [14C]-labelled putative adenosine 3′, 5′ -cyclic monophosphate (cAMP) and marker authentic [3H] -cAMP was characterized by chemical deamination and also by the enzymatic hydrolysis with beef heart cyclic nucleotide phosphodiesterase. A significant conversion of marker authentic [3H] -cAMP into [3H] -inosine 3′, 5′ -cyclic monophosphate (cIMP) and [3H] -5′ adenosine monophosphate was observed by respective treatments. In contrast, the [14C] -labelled putative cAMP from control and theophylline-treated moss tissue was insensitive to chemical deamination and enzymatic hydrolysis. Apparently, the [14C] -labelled product which comigrates with authentic [3H] -cAMP does not represent true cAMP. Both the methods employed for characterization of the labelled putative cAMP were sensitive enough to detect picomole quantities of authentic [3H] -cAMP. Lack of detectability of prelabelled [14C] -cAMP in our preparations implies that the tissue may contain authentic cyclic AMP below the picomole levels. Thus, the attributed physiological role to adenosine 3′, 5′ -cyclic monophosphate in moss tissue appears somewhat skeptical. 相似文献
13.
A comparison has been made between the capacity to hydrolyse 2′,3′-cyclic adenosine monophosphate and 3′,5′-cyclic adenosine monophosphate in subcellular fractions of normal and neoplastic (lymphosarcoma) spleen of C57BL mice. The effect of X-irradiation on these activities was tested. Subcellular fractionation of normal and lymphosarcoma spleen points to a different overall localization of the enzymes. The 2′,3′-cyclic nucleotide phosphodiesterase (2′,3′-cAMPase) has its highest specific activity in the particulate fractions of the cell, while the data on 3′,5′-cyclic nucleotide phosphodiesterase (3′,5′-cAMPase) show the highest activity in the soluble fraction. The 2′,3′-cAMPase activity is higher in the tumor as compared to the normal tissue, while the opposite holds for 3′,5′-cAMPase. Total body irradiation of normal mice with a dose of 600 rads of X-rays, results in a clear drop in 2′,3′-cAMPase 48 hours after the exposure. The 3′,5′-cAMPase is hardly affected at this time. Neither imidazol nor Mg++ has any influence on the 2′,3′-cAMPase. The pH optimum for 3′,5′-cAMPase and 2′,3′-cAMPase appears to be 7.7 and 6.2 respectively. This report suggests a no-identity of the two enzymes in mouse spleen, a situation different from that found in certain plants. 相似文献
14.
R.H. Symons 《Biochimica et Biophysica Acta (BBA)/General Subjects》1973,320(2):535-539
A general procedure is described for the two-step chemical synthesis from [32P]orthophosphoric acid of the eight common ribo- and deoxyribonucleoside 3′,5′-cyclic monophosphates. The method is simple and reliable and both steps are carried out in the same reaction flask without an intermediate purification step. 32P-labelled cyclic nucleotides are obtained after paper chromatography in yields of 20–60% relative to starting [32P]orthophosphoric acid and with a specific activity of greater than 1 mCi/μmole. Alternative methods for the purification of reaction mixtures and for the preparation of 32P-labelled 3′,5′-cyclic AMP and 3,′,5′-cyclic GMP are described. 相似文献
15.
Comparison between rat and rabbit anticyclic AMP antibodies--specificity toward acyl derivatives of cyclic AMP 总被引:2,自引:0,他引:2
This paper deals with the specificity of the anti 3′,5′-cyclic AMP antibodies which can be obtained with 2′-O-succinyl cyclic AMP-albumin as an immunogen. The binding of the hapten and its analogs was measured by equilibrium dialysis. Rat and rabbit antibodies were compared. In both cases the best ligands for the anti-hapten antibodies are 2′-O-acylated derivatives of cyclic AMP: the dissociation constants are below 10?10m. Cyclic AMP itself and its 6 N, 2′-O-diacylated derivatives are recognized less efficiently; their dissociation constants lie around 10?8m, similar to that of natural cyclic AMP binding proteins. Other nucleotides lacking either adenine or the 3′,5′-phosphate ring are not recognized. Three different populations of antibodies were detected by a more detailed analysis of the equilibrium curves. 相似文献
16.
P. Raymond A. Narayanan A. Pradet 《Biochemical and biophysical research communications》1973,53(4):1115-1121
3′, 5′-cyclic AMP has been highly purified by chromatography from sterile higher plant tissues and assayed by bioluminescence as well as by activation of protein kinase. Both methods give comparable results: the amount of cyclic AMP was found to vary between 30 and 200 pmoles per mg of protein nitrogen. 相似文献
17.
–Adenosine 3′,5′-cyclic monophosphate (cyclic AMP) levels increase about 5-fold in the cerebral cortex and 2-fold in the cerebellum following electroconvulsive shock (ECS). The peak levels of cyclic AMP occur at 45 s after ECS in the cerebral cortex, and at 15 s in the cerebellum. In the cerebral cortex, ECS produces twice the cyclic AMP accumulation as does decapitation in a comparable time period; however, the relative effect of a number of neurotropic agents on the cyclic AMP accumulation is essentially the same, whether stimulated by decapitation or by ECS. In the cerebellum, the levels of guanosine 3′,5′-cyclic monophosphate (cyclic GMP) also increase following ECS. The cyclic GMP levels are greatest at 60 s after ECS during the postictal depression. An association between elevated cerebellar cyclic GMP and depression seems unlikely, since CNS depressants either lowered or had no effect on cyclic GMP levels. From these results, cyclic nucleotide profiles following treatments such as ECS or decapitation may be useful in elucidating the molecular events involved in seizures, brain injury and ischemia. 相似文献
18.
Cartilage cyclic nucleotide phosphodiesterase: inhibition by anti-inflammatory agents 总被引:8,自引:0,他引:8
Soluble 3′,5′-nucleotide phosphodiesterase (PDE) activity is described in chicken epiphyseal and articular cartilage. Kinetic studies of these enzymes demonstrate a high and low Km for the substrates, adenosine 3′,5′-cyclic monophosphate (cyclic AMP) and guanosine 3′,5′-cyclic monophosphate (cyclic GMP). Epiphyseal and articular PDE activities are inhibited by those anti-inflammatory agents which are potent inhibitors of the enzyme, prostaglandin synthetase (PS). Specificity of this inhibition is indicated by the activity of these agents against the low Km enzyme. Other anti-inflammatory agents with significantly less potency as PS inhibitors or with no activity against prostaglandin synthetase are found to be either inactive or relatively less potent as inhibitors of cartilage PDE activity. A variety of other anti-inflammatory or anti-rheumatic agents, which are not known to affect prostaglandin synthetase activity, are poor inhibitors of cartilage PDE activity. These data provide insight into the mechanism of action of certain anti-inflammatory agents and into the relationships between prostaglandins and inflammatory reactions. 相似文献
19.
Infrared spectra of neutral aqueous solutions of nucleoside 3′,5′-cyclic monophosphates indicate an increase in the antisymmetric phosphoryl stretching frequency to 1236 cm?1 from 1215 cm?1 in trimethylene cyclic phosphates. A further increase to 1242 cm?1 accompanies esterification of the 2′-ribose hydroxyl. The O2′-esterified and 2′-deoxy cyclic nucleotides examined display both reduced kinase binding and altered phosphoryl stretching frequencies, suggesting that modification of the phosphate ring represents a common feature in decreased kinase activation. Reversible inhibition of mitosis in thymidine-synchronized human lymphocytes by 2 mmN6,O2′-dibutyryladenosine 3′,5′-cyclic monophosphate and N6-monobutyryladenosine 3′,5′-cyclic monophosphate was observed. However, adenosine 3′,5′-cyclic monophosphate, O2′-monobutyryladenosine 3′,5′-cyclic monophosphate, butyric acid, and ethyl butyrate had no effect on mitosis when present at 2 mm concentrations during S and G2. These results are consistent with hydrolysis of O2′-monobutyryladenosine 3′,5′-cyclic monophosphate and adenosine 3′,5′-cyclic monophosphate by esterase and phosphodiesterase enzymes and suggest that modification of the N6 amino group is necessary for the antimitotic activity of N6,O2′-dibutyryladenosine 3′, 5′-cyclic monophosphate. 相似文献
20.
An enzyme, which hydrolyzes 3′,5′-cyclic AMP to 3′-AMP and 5′-AMP, has been isolated from dormant tubers of Jerusalem artichoke and purified 850 × with a recovery of 15% of total activity. The partially purified enzyme differs greatly from both animal and bacterial phosphodiesterases in terms of pH optimum, substrate specificity, cation dependence and sensitivity to methylxanthines. The plant hormones are without effect, whereas ATP, 5′-AMP, 3′-AMP, inorganic phosphate and pyrophophosphate are inhibitors. The enzyme seems to be greatly inhibited in vivo by inorganic phosphate during dormancy. 相似文献