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221.
222.
A rapid procedure for the construction of PCR cDNA libraries from small amounts of plant tissue 总被引:6,自引:0,他引:6
Ian Jepson John Bray Gareth Jenkins Wolfgang Schuch Keith Edwards 《Plant Molecular Biology Reporter》1991,9(2):131-138
We describe a general method for the preparation of λZAP II cDNA libraries from very small amounts (<50 mg) of plant tissue.
We have achieved this by combining an efficient method for RNA extraction with a modified PCR protocol for the synthesis and
amplification of cDNA. Using this protocol we have found it possible to generate cDNA libraries containing more than 106 clones from as little as 1 μg of total RNA. 相似文献
223.
The biodegradation of anthracene-9, 10-diethanol by the ligninolytic fungus Phanerochaete chrysosporium, previously though to involve singlet oxygen, is shown to be catalyzed by lignin peroxidases. Veratryl alcohol stimulated the enzymatic degradation of anthracenediethanol, and anthracenediethanol inhibited enzymatic oxidation of veratryl alcohol. Competition for oxidation by lignin peroxidase is suggested as the mechanism of the inhibition of lignin biodegradation by anthracenediethanol and related anthracene derivatives.Abbreviations ADE
anthracene-9,10-diethanol
- AES
anthracene-9,10-bisethanesulfonic acid
- DHP
dehydrogenative polymerizate
- DMF
N,N-dimethylformamide
- EPX
9,10-endoperoxide of ADE
- PMR
proton magnetic resonance 相似文献
224.
Ian Close Gareth Shackleton Peter S. Goldfarb G. Gordon Gibson Raj Sharma Doug Howes 《Journal of biochemical and molecular toxicology》1992,7(3):193-198
The influence of both single and concurrent administration of phenobarbital and clofibrate on hepatomegaly, cytochrome P450-depen-dent mixed function oxidase activities, and peroxisome proliferation in male rat liver have been studied. Both xenobiotics separately increase the liver :body weight ratio and their combined administration results in greater hepatomegaly than either compound alone. Both compounds induce NADPH-cytochrome c(P450) reductase activity and laurate ω- and ω-1-hydroxylase activities, but only phenobarbital induces pentoxyresorufin-O-de-alkylase. None of the drug treatments induced microsomal cytochrome b5. Phenobarbital did not cause peroxisome proliferation and inhibited the corresponding clofibrate-dependent proliferation. Taken collectively, our studies have demonstrated that concomitant treatment with phenobarbital and clofibrate are largely permissive with respect to the hepatic mixed function oxidase system but have opposing effects on the phenomenon of peroxisome proliferation in the same tissue. 相似文献
225.
226.
Amy L. Dingley Kenneth Kustin Ian G. Macara Guy C. Mcleod Mary F. Roberts 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1982,720(4):384-389
The intracellular pH of intact blood cells of the tunicate Ascidia nigra was measured by transmembrane equilibration of [14C]methylamine. The pH of unfractionated blood cells is 7.39±0.10. The pH of vanadocytes, determined in a fractionation study, is 7.2. Previously used methods, in which pH values less than 3.0 are inferred from cell lysis or vital staining experiments, are shown to be unsuitable for intracellular pH determination due to the chemical composition of these vanadium-containing cells. 相似文献
227.
Summary Tench (Tinca tinca) were acclimated to either aerated (P
O
2 17.6 KPa) or hypoxic (P
O
2 1.5 KPa) water for 6 weeks.Acclimation to hypoxia resulted in a decrease in mitochondrial volume fraction in both slow (22.9 to 15.0 %) and fast glycolytic (4.5 to 1.8 %) myotomal muscles fibres (P<0.01).Intermyofibrillar mitochondrial populations (4.4 to 1.2% slow; 0.6 to 0.04% fast fibres) were affected to a greater extent than those in the subsarcolemmal zone (18.5 to 13.8% slow; 3.9 to 1.8% fast fibres). After acclimation to hypoxia, cytochrome-oxidase activities decreased by 31 and 33 % in slow and fast fibres, respectively, but were maintained in the liver.Fibre size remained unchanged and actively differentiating fibres were observed in muscles from both groups of fish. Hypoxia resulted in a significant increase in myofibrillar volume fraction in both slow (43.1 to 56.1 %) and fast glycolytic fibres (73.1 to 82.7%) (P<0.05).Glycogen concentrations (mg/100g tissue) for liver (6616) slow muscle (1892) and fast muscle (334) were similar for fish acclimated to aerated or hypoxic water. Acclimation to hypoxia increased carnitine palmitoyl transferase activity (moles substrate utilised g·dry wt-1 min-1) in slow (0.42 to 1.1), fast glycolytic muscle (<0.01 to 0.15) and liver (1.1 to 3.7) indicating an enhanced capacity for fatty acid oxidation.Phosphofructokinase activities of fast glycolytic fibres were similar in fish acclimated to either aerated or hypoxic water, consistent with an unaltered capacity for anaerobic glycogenolysis. Hexokinase activities (moles substate utilised, g·dry wt-1 min-1) decreased in fast fibres (1.2 to 0.4) but were maintained in the slow muslce (2.1 to 2.5) and liver (4.5 to 4.8) of hypoxic fish. The activities of phosphofructokinase in slow muscle and phosphofructokinase, pyruvate kinase and lactate dehydrogenase in liver were two times higher in fish acclimated to hypoxia. An enhanced capacity for glycolysis in these tissues may reflect a reduced threshold for anaerobic metabolism during activity and/or an adaptation for acute exposure to anoxia in fish acclimated to hypoxia.Abbreviations/Glossary CO
cytochrome oxidase activity
- CPT
carnitine palmitoyltransferase activity
- HK
hexokinase activity
- LDH
lactate dehydrogenase activity
- PFK
phosphofructokinase activity
- PK
pyruvate kinase activity
- Vv
volume fractions of cell components
- normoxic
fish acclimated to aerated water
- hypoxic
fish acclimated to reduced oxygen tensions
-
P
O
2
partial pressure of oxygen tension
A preliminary account of part of this work was presented at theXth European Meeting on Muscle and Cell Motility held at Galway, Ireland, in September 1981 相似文献
228.
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230.