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1.
Crude extracts or supernatants of broken cells of Clostridium formicoaceticum reduce unbranched, branched, saturated and unsaturated carboxylates at the expense of carbon monoxide to the corresponding alcohols. The presence of viologens with redox potentials varying from E
0=-295 to-650 mV decreased the rate of propionate reduction. The more the propionate reduction was diminished the more formate was formed from carbon monoxide. The lowest propionate reduction and highest formate formation was observed with methylviologen. The carbon-carbon double bond of E-2-methyl-butenoate was only hydrogenated when a viologen was present. Formate as electron donor led only in the presence of viologens to the formation of propanol from propionate. The reduction of propionate at the expense of a reduced viologen can be followed in cuvettes. With respect to propionate Michaelis Menten behavior was observed. Experiments are described which lead to the assumption that the carboxylates are reduced in a non-activated form. That would be new type of biological reduction.Non-standard abbreviations glc
Gas liquid chromatography
- HPLC
high performance liquid chromatography
- RP
reverse phase; Mediators (the figures in parenthesis of the mediators are redox potentials E
0 in mV)
- CAV2+
carbamoylmethylviologen, 1,1-carbamoyl-4,4-dipyridinium dication (E
0=-296 mV)
- BV2+
benzylviologen, 1,1-dibenzyl-4,4-dipyridinium dication (E
0=-360 mV)
- MV
methylviologen, 1,1-dimethyl-4,4-dipyridinium-dication (E
0=-444 mV)
- DMDQ2+
dimethyldiquat, 4,4-dimethyl-2,2-dipyridino-1,1-ethylendication (E
0=-514 mV)
- TMV2+
tetramethylviologen, 1,1,4,4-tetramethyl-4,4-dipyridinium dication (E
0=-550 mV)
- PDQ2+
propyldiquat, 2,2-dipyridino-1,1-propenyl dication (E
0=-550 mV)
- DMPDQ2+
dimethylpropyldiquat, 4,4-dimethyl-2,2-dipyridino-1,1-propenyl dication (E
0=-656 mV)
- PN
productivity number=mmol product (obtained by the uptake of one pair of electrons) x (biocatalyst (dry weight) kg)-1×h-1 相似文献
2.
Summary Data has been obtained concerning the reduction of tetrazolium salts by mitochondria isolated from Jerusalem artichoke tubers with succinate as the substrate using a direct recording spectrophotometric method of assay. ATP was found to increase the rate of reduction of the tetrazolium salts, this being independent of the effect ATP had on the rate of oxygen uptake. The magnitude of the stimulation by ATP depended on the concentration of tetrazolium salts present and under certain circumstances was suppressed by the addition of azide and cyanide. The sites at which the tetrazolium salts were reduced along the electron transport chain were investigated. The role of ATP has been discussed in relation to the mechanism of tetrazolium reduction.Abbreviations TTC
2,3,5-triphenyl-2,1,3,4-tetrazolium chloride
- BT
5,5-diphenyl-3,3-(3,3-dimethoxy-4,4-diphenylene)-ditetrazolium chloride
- NT
2,2,5,5-tetraphenyl-3,3-(p-diphenylene)-ditetrazolium chloride
- MTT
3-(4,5-dimethyl thiozolyl-2)-2,5-diphenyl tetrazolium bromide
- INT
2-(p-iodophenyl)-3-p-dinitrophenyl-3-p-nitrophenyl-5-phenyl tetrazolium chloride
- NBT
2,2-dinitrophenyl-5,5-diphenyl-3,3-dimethoxy-4,4-diphenylene)-ditetrazolium chloride
- TNBT
2,2-5,5-tetra-p-nitrophenyl-3,3-dimethoxy-4,4-diphenylene) ditetrazolium chloride 相似文献
3.
Four radiolabled congeners of biphenyls with increasing chlorine content (biphenyl; 1-monochlorobiphenyl; 2,2,4,4-tetrachlorobiphenyl; and 2,2,4,4,5,5-hexachlorobiphenyl) were provided to suspension cultures of rose (Rosa sp. cv. Paul's Scarlet) for 4 days. Both the kinetics of 14C exchange between the cells and medium, and the metabolism of the parent compounds depended on the chlorine content of the congeners. Analysis of both the cells and their medium showed that of the recovered radioactivity 88%, 86%, and 3% of the biphenyl, 1-PCB, and 2,2,4,4-PCB were metabolized respectively to polar and insoluble residue products. The 2,2,4,4,5,5-PCB did not appear to be metabolized. 相似文献
4.
Brian A. McGaw Roger Horgan Jim K. Heald George J. Wullems Rob A. Schilperoort 《Planta》1988,176(2):230-234
The levels of the major cytokinins, zeatin, zeatin riboside, zeatin riboside-5-monophosphate and zeatin-7-glucoside were measured in tobacco (Nicotiana tabacum L.) crown-gall tissues carrying insertion and deletion mutations in the T-DNA. Measurements were made by combined gas chromatography-mass spectrometry using selected ion monitoring with 15N- and 2H-labelled internal standards. The results demonstrate that, relative to wild-type tumour tissue, cytokinin levels are considerably elevated in tissues lacking functional T-DNA auxin-biosynthetic genes. From a detailed analysis of the major cytokinin metabolites it is concluded that a reduction in the extent of cytokinin degradation via N6-side-chain cleavage is an important factor leading to increased cytokinin levels in these tissues.Abbreviations IAA
indole-3-acetic acid
- SIM
selected ion monitoring
- Z
zeatin
- [7G]Z
zeatin-7-glucoside
- [9R]Z
zeatin-9-riboside
- [9R-5P]Z
zeatin riboside-5-monophosphate 相似文献
5.
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
6.
The carotenoid pigments of a Rhizobium strain isolated from Lotononis bainesii were found to be diglucosyl-4,4-diapocarotene-4,4-dioate and glucosyl-4,4-diapocarotene-4-oate-4-oic acid.5th publication in the series Carotenoids of Rhizobia [4th publication: Helv. chim. Acta 62: 2551–2557 (1979)] 相似文献
7.
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
8.
the cytokinins of tobacco crown-gall tissue have been analysed by quantitative mass spectrometry using 2H2-labelled cytokinin riboside 5-monophosphates and 15N4-labelled cytokinin glycosides as internal standards. The principal endogenous cytokinin of this tissue is zeatin riboside 5-monophosphate. The biologically inactive 7-glucoside of zeatin is the most abundant basic cytokinin in the tissue. These findings expose the limitations of previously reported analyses of similar tissues, which were restricted to biologically active basic cytokinins. The present study demonstrates that the endogenous cytokinins of tobacco crowngall tissue show a clear correspondence to the range of metabolites formed when exogenous cytokinins are supplied to nontumorous tobacco cells.Abbreviations DHZ
dihydrozeatin
- DHZ7G
dihydrozeatin 7-glucoside
- DHZMP
dihydrozeatin 9-riboside 5-monophosphate
- DHZR
dihydrozeatin 9-riboside
- GC-MS
coupled gas chromatography-mass spectrometry
- HPLC
high-performance liquid chromatography
- Z7G
zeatin 7-glucoside
- Z9G
zeatin 9-glucoside
- ZOG
zeatin O-glucoside
- ZMP
zeatin 9-riboside 5-monophosphate
- ZR
zeatin 9-riboside
- ZROG
zeatin 9-riboside O-glucoside 相似文献
9.
Alan Shaver Jesse B. Ng David A. Hall Barry I. Posner 《Molecular and cellular biochemistry》1995,153(1-2):5-15
The inorganic coordination chemistry of peroxovanadium compounds relevant to insulin mimesis is reviewed. The structure and kinetic reactivity of solutions of vanadate anion, vanadyl complexes and peroxovanadate complexes are briefly compared. Peroxovanadium compounds contain an oxo group, one or two peroxo ligands (O2
2–) and an ancillary ligand which is usually bidentate. These compounds approximate a trigonal bipyramidal structure which can be divided conceptually into a polar oxo half and a relatively non-polar organic half. This presents a number of interesting design variations which are discussed with respect to the development of a rudimentary structure-activity correlation of insulin mimetic ability.Abbreviations phen
1,10-phenanthroline
- 4,7-Me2phen
4,7-dimethyl-1,10-phenanthroline
- 3,4,7,8-Me4phen
3,4,7,8-tetramethyl-1,10-phenanthroline
- 5-CH3phen
5-methyl-1,10-phenanthroline
- 5-NO2phen
5-nitro-1,10-phenanthroline
- 5-NH2phen
5-amino-1,10-phenanthroline
- bipy
2,2-bipyridine
- bipyH
2,2-bipyridinium
- 4,4-Me2bipy
4,4-dimethyl-2,2-bipyridine
- bipy-4,4-(COO)2
2,2-bipyridine-4,4-dicarboxylato
- pic
pyridine-2-carboxylato
- 3-OHpic
3-hydroxypyridine-2-carboxylato
- 3-acetpic
3-acetatoxypyridine-2-carboxylato
- m,n-pdc
pyridine-m,n-dicarboxylato
- ox
oxalato
- pzc
pyrazine-2-carboxylato
- 3-NH2pzc
3-aminopyrazine-2-carboxylato
- 4OH-2,6pdc
4-hydroxy-2,6-pyridinedicarboxylato
- IDA
iminodiacetato
- cit
citrato
- EDTA
ethylenediaminetetraacetato
- HEDTA
ethylene-diaminetetraacetic acid
- isoquin
isoquinoline-2-carboxylato
- quin
quinolato
- NTA
nitrilotriacetato
- glyH
glycine
- cystH
cysteine
- nicH
nicotinic acid
- Hheida
N-(2-hydroxyethyl)iminodiacetato 相似文献
10.
The respiratory quinone composition of the obligate methane-utilizing bacterium Methylomonas rubra was examined. A single lipoquinone was isolated which on examination by thin-layer chromatography cochromatographed with coenzyme Q. Reverse-phase partition and argentation high performance liquid chromatography demonstrated the lipoquinone did not correspond to any known coenzyme Q prenologue. On the basis of mass spectrometry and proton nuclear magnetic resonance spectrometry the novel lipoquinone was shown to correspond to 2,3-dimethoxy-5-methyl-6-(11-methylene-3,7,15, 18, 18, 19, 23-heptamethyltetracosa-2, 6, 14, 19, 22-pentaenyl-)-1,4-benzoquinone. 相似文献
11.
During chloroplast development in the primary leaves of Phaseolus vulgaris, the extractable activity of adenosine 5-phosphosulfate sulfotransferase increased ten-fold. When chloroplast development took place in air enriched with 3.5 l H2S·l-1 there was a decrease in adenosine 5-phosphosulfate sulfotransferase activity. Cyst(e)ine in concentrations up to 1 mM (in the external medium) did not affect the increase in adenosine 5-phosphosulfate sulfotransferase activity in intact plants. In plants with excised roots, 0.75 mM cyst(e)ine inhibited this increase. In green primary leaves, H2S or cyst(e)ine treatment resulted in a decrease of extractable adenosine 5-phosphosulfate sulfotransferase activity. In intact plants, this effect of cyst(e)ine was observed at a concentration of 1 mM, and in plants with excised roots, 0.25 mM had a comparable effect.In developing plants, the extractable activities of O-acetyl-L-serine sulfhydrylase (EC 4.2.99.9) and ribulosebisphosphate carboxylase (EC 4.1.1.39.) were not affected by H2S or cyst(e)ine.Abbreviations APS
adenosine 5-phosphosulfate
- APSSTase
adenosine 5phosphosulfate sulfotransferase
- BSA
bovine serum albumin
- DTE
dithioerythritol
- EDTA
ethylenediaminetetra-acetic acid
- OASSase
O-acetyl-L-serine sulfhydrylase
- PAPS
adenosine 3-phosphate 5-phosphosulfate
- POPOP
1,4 Di 2-(5-phenyloxazolyl)-benzene
- PPO
2,5-diphenyloxazol
- RubP
ribulose-bisphosphate
- RubPCase
ribulosebiphosphate carboxylase
This is no. 8 in the series Regulation of Sulfate Assimilation in Plants. The term cysteine is used when it is clear that cystine is not involved; cyst(e)ine is used for an undefined mixture of cysteine and cystine. The concentrations are expressed in all cases relative to cysteine 相似文献
12.
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
13.
Direct evidence has been obtained for the presence of adenosine-3:5-cyclic monophosphate (cAMP) in tobacco (Nicotiana tabacum L.) callus tissue cultures, bean (Phaseolus vulgaris L.) seedlings and immature kernels of sweet corn (Zea mays L.) through the use of a highly specific and sensitive gas chromatography-mass spectrometric assay. Levels of endogenous cAMP ranged from 70 to 126 pmol/g fresh weight. Corresponding levels of cAMP determined for the same samples using radioimmunoassay were consistently three to four times higher. Contrary to previous reports for citrus plants, measurable levels of cAMP could not be detected in young lemon leaves within the limits of detection of the mass-spectrometric assay method. In the case of tobacco callus tissue, the coumarin glucoside, scopolin, which was present in large amounts and showed similar chromatographic behaviour to cAMP, interferred strongly with the mass-spectrometric measurements of cAMP in inadequately purified extracts. The use of high-performance liquid chromatography, in addition to standard chromatographic purification methods, produced highly purified plant extracts for quantitation of cAMP and also provided a method for the separation of cAMP from its 2:3-isomer.Abbreviations cAMP
adenosine-3:5-cyclic monophosphate
- 2:3-cAMP
adenosine-2:3-cyclic monophosphate
- GC-MS-MID
combined gas chromatography-mass spectrometry with selected multiple-ion-detection
- HPLC
high-performance liquid chromatography
- RIA
radioimmunoassay
- TLC
thin-layer chromatography 相似文献
14.
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
15.
Potential importance of protozoan grazing on the accumulation of polychlorinated biphenyls (PCBs) in the pelagic food web 总被引:2,自引:0,他引:2
Experiments were conducted to study the distribution of three selectedpolychlorinated biphenyl (PCB) congeners within the microbial food web attwo different nutrient levels; control and nutrient enriched. The objectivewas to quantify the uptake of PCBs through grazing by protozoa. The14C-PCBs tested were 4-chlorobiphenyl (IUPAC # 3),2,2,5,5-tetrachlorobiphenyl (IUPAC # 52), and2,2,4,4,5,5-hexachlorobiphenyl (IUPAC # 153). EachPCB was incubated in triplicate seawater samples at 20 idref;Cover one week. Daily, samples were separated into four fractions; <0.2µm (dissolved), 0.2-2 µm (bacteria), 2-10 µm(flagellate), and > 10 µm (microplankton; phytoplankton andprotozoa) by selective filtration. Of the PCB fraction that initiallyadsorbed to particles, 60–100% was associated to the bacterialfraction and 0–5% to the microplankton fraction. The totaluptake was highest in the nutrient enriched samples, but when normalized tothe carbon biomass the concentration was lower or equal to the control inall particle fractions. The recovery of the PCBs in the particulatefractions depended on the degree of chlorination, as the highest values wereobserved for the 2,2,4,4,5,5-hexachlorobiphenyl and thelowest for the 4-chlorobiphenyl. The concentrations in the bacterial andflagellate fractions decreased over the first 48–96 hours whilst theconcentration increased in the highest trophic level (>10 µmfraction). Approximately 75% of the increase in concentration of the2,2,4,4,5,5-hexachlorobiphenyl in the > 10 µmfraction was estimated to be the result of bacterivory. Our results indicatethe microbial food web can contribute to a rapid uptake of higherchlorinated PCBs, particularly in oligotrophic ecosystems where thebacterial biomass dominates. 相似文献
16.
Studies were conducted to assess the effects of inducers of hepatic mixed function oxidases on DNA repair responses to 13 different genotoxic agents in hepatocytes from adult male mice. Phenobarbital pretreatment increased DNA repair elicited by diethylnitrosamine but had no effect on responses to the other compounds. Pretreatment with p,p-dichlorodiphenyltrichloroethane, 3-methylcholanthrene or -naphthoflavone induced the DNA repair responses to a variety of activation-dependent carcinogens. DNA repair responses to the direct-acting alkylating agents methyl methanesulfonate and N-methyl-N-nitro-N-nitrosoguanidine were not increased by any of the pretreatments, which indicated that the pretreatment-related enhancement of responses to the other compounds was due to induction of their metabolic activation. Taken together, the findings suggest that Aroclor, or other pretreatments, may increase the sensitivity of the hepatocyte DNA repair assay for detecting the genotoxicity of certain compounds; however, the potential benefit may be limited due to specific features of the assay. In contrast, Aroclor pretreatment did not produce any enhancement of in vivo DNA repair elicited by dimethylnitrosamine, diethylnitrosamine, o-aminoazotoluene, 2-acetylaminofluorene, 3-methylcholanthrene or aflatoxin B1, and thus does not appear to be useful for improving the sensitivity of the in vivo/in vitro assay.Whereas the amount of DNA repair produced by dimethylnitrosamine was not increased by classical inducers of liver microsomal enzymes, pretreatment with pyrazole greatly augmented in vitro and in vivo DNA repair responses to dimethylnitrosamine; responses to diethylnitrosamine were increased to a lesser degree by pyrazole pretreatment. The effects of lactational exposure to enzyme inducing agents on DNA repair in neonatal hepatocytes was also investigated.Abbreviations 2-AAF
2-acetylaminofluorene
- 4-AB
4-aminobiphenyl
- 6-AC
6-aminochrysene
- AFB
aflatoxin B1
- ARO
Aroclor 1254
- o-AT
o-aminoazotoluene
- B(a)P
benzo[a]pyrene
- B-NF
beta-naphthoflavone
- BZ
benzidine
- DDT
p,p-dichlorodiphenyltrichloroethane
- DDE
p,p-dichlorodiphenyldichloroethylene
- DEN
diethylnitrosamine
- DMBA
7,12-dimethylbenzanthracene
- DMN
dimethylnitrosamine
- 3-MC
3-methylcholanthrene
- MMS
methyl methanesulfonate
- MNNG
N-methyl-N-nitro-N-nitrosoguanidine
- 2-NA
2-naphthylamine
- NNG
net nuclear grains
- PB
phenobarbital
- PYR
pyrazole 相似文献
17.
Robert Langenbach Kenneth Rudo Scott Ellis Cathy Hix Stephen Nesnow 《Cell biology and toxicology》1987,3(3):303-319
The metabolism and mutagenicity of 2-acetylaminofluorene were measured using freshly prepared intact bladder and liver cells from the cow, dog and rat. High pressure liquid chromatography was used to separate 2-acetylaminofluorene metabolites, andSalmonella typhimurium, strain TA98, was used to detect mutagenic intermediates. Species differences as well as animal-to-animal variation within a species were observed. Mutagenic activity with 2-acetylaminofuorene was greater with cow bladder cells than with dog or rat bladder cells. However, dog bladder cells were most active in metabolizing 2-acetylaminofluorene, and rat bladder cells were least active. Liver cells from all three species metabolized 2-acetylaminofluorene to mutagens forSalmonella, with dog and cow cells being more active than rat liver cells. However, cow liver cells were the most active in metabolizing 2-acetylaminofuorene, followed by rat and dog cells. With all cell types studied, except rat bladder cells, aminofluorene was the major metabolite detected. Carbon and N-hydroxylated products were produced by liver and bladder cells of the three species and glucuronide and sulfate conjugates of the metabolites were detected from both cell types. Correlations between mutagenic activity and the level of metabolism or any individual metabolite were not apparent. The data suggest that the relative contribution of bladder cell metabolism in aromatic amine induced bladder cancer may vary with the species.Abbreviations AAF
2-acetylaminofluorene
- 4-ABP
4-aminobiphenyl
- AF
aminofluorene
- BZ
benzidine
- cytochrome P-450
a collective term for all forms of the cytochrome P-450 polysubstrate mono-oxygenases
- FMO
flavin mono-oxygenases
- HPLC
high pressure liquid chromatography
- MNNG
N-methyl-N-nitro-N-nitrosoguani-dine
- 2-NA
2-naphthylamine
- N-OH-AAF
N-hydroxy-2-acetylaminofluorene
- 1-OH-AAF
1-hydroxy-2-acetylaminofluorene
- 5-OH-AAF
5-hydroxy-2-acetylaminofluorene
- 7-OH-AAF
7-hydroxy-2-acetylaminofluorene
- 8OH-AAF
8-hydroxy-2-acetylaminofluorene
- 9-OH-AAF
9-hydroxy-2-acetylaminofluorene
- UDS
unscheduled DNA synthesis 相似文献
18.
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
19.
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
20.
We demonstrate in this work that HCO
inf3
sup–
uptake in the marine macroalga Ulva sp. features functional resemblances to anion transport mediated by anion exchangers of mammalian cell membranes. The evidence is based on (i) competitive inhibition of photosynthesis by the classical red-blood-cell anion-exchange blockers 4,4-dinitrostilbene-2,2-disulfonate and 4-nitro-4-isothiocyanostilbene-2,2-disulfonate under conditions where HCO
inf3
sup–
, but not CO2, was the inorganic carbon form taken up; (ii) inhibition of HCO
inf3
–
uptake by pyridoxal phospate, indicating the involvement of lysine residues in the binding/translocation of HCO
inf3
sup–
; and (iii) inhibition of HCO
inf3
sup–
(but not of CO2) uptake by exofacial trypsin treatments, indicating the functional involvement of a plasmalemma protein. It is suggested that HCO
inf3
sup–
uptake mediated by such a putative anion transporter can be a fundamental step in providing inorganic carbon for the CO2-concentrating system of marine marcoalgae in an environment where the HCO
inf3
sup–
concentration is high, but the CO2 concentration and rates of uncatalyzed HCO
inf3
sup–
dehydration are low.Abbreviations CI
ionorganic carbon
- DIDS
4,4-diisothiocyanostilbene-2,2-disulfonate
- DNDS
4,4-dinitrostilbene-2,2-disulfonate
- NIDS
4-nitro-4-isothiocyanostilbene-2,2-disulfonate
- PLP
pyridoxal phosphate
- Rubisco
ribulose-1,5-bisphosphate carboxylase-oxygenase 相似文献