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81.
Pyrroline-5-carboxylate reductase, which required reduced pyridine nucleotide and Δ′-pyrroline-5-carboxylate for proline synthesis, was isolated from pumpkin cotyledons. The enzyme was found in the soluble fraction and had a 4.5-fold greater activity with NADH than NADPH. The enzyme was inhibited by NH2OH, NADP, ATP and slightly by proline. Glutathione or pyridoxal-5-phosphate had little effect on enzyme activity. The enzyme had a pH optimum between 7·0 and 7·6 and was not inhibited by high concentrations of NADH or Δ′-pyrroline-5-carboxylate. 相似文献
82.
The estrogen of the doum palm kernel and pollen grains has been isolated as the p,p′-nitrophenylazo benzoyl derivative and identified as estrone. 相似文献
83.
A new nematode genus, Nothacrobeles, is proposed in the subfamily Acrobelinae. Four new species are described and one new combination made. The five species exhibit a progression from short-to-long, bifurcate, elaborately fringed labial probolae, the longest probolae resembling those of species of Acrobeles. 相似文献
84.
Hepatic alcohol dehydrogenase activity and mass content change coordinately during development in male rats. Enzyme activity and mass content increase continuously after birth to 100 and 80% of maximal values within 6 weeks (2.6 ± 0.4 μmole/min/g liver and 92 ± 20 μg/g liver), respectively. When expressed per milligram of soluble proteins, both parameters peak at 3 weeks (0.052 ± 0.002 μmole/min/mg protein and 2.0 ± 0.4 μg/mg protein) and then decrease gradually to plateau levels. These decreases probably arise from a “surge” in soluble liver protein levels that occurs after weaning. Similar developmental patterns also occur in female rats. These findings are the first quantitative measurements of this enzyme in developing animals. 相似文献
85.
Two new propagule-farming red algae from southern Australia, Deucalion levringii (Lindauer) gen. et comb. nov. and Anisoschizus propaguli gen. et sp. nov., are described and defined largely on their development in laboratory culture. Deucalion is included in the tribe Compsothamnieae on the basis of its subapical procarp and alternate distichous branching. It differs from the other genera included in that tribe in that it produces 3-celled propagules, polysporangia, a subapical cell of the fertile axis which bears 3 pericentral cells, and an apparently post-fertilization involucre which develops from the hypogenous and sub-hypogenous cells of the fertile axis. Its gametophyte morphology has been elucidated in culture, as only sporophytes are known from the field. Gametophytes do not appear to produce propagules. Anisoschizus is provisionally included in the tribe Spermothamnieae on the basis of its subdichotomous branching, possession of a prostrate system and the production of polysporangia. It differs from the other genera of the tribe in the production of 2-celled propagules. Observations on the germination of the “monosporangia” of Mazoyerella arachnoidea and Monosporus spp. indicate that they are analagous to the propagules of Deucalion and Anisoschizus. The nature of these propagules and their role in recycling the parent plant are discussed and contrasted with true monosporangia. It is recommended that Monosporus be maintained as a form genus containing representatives from more than one tribe, as exemplified by plants from Lord Howe I. provisionally identified as M. indicus Boergesen which have both prostrate and erect, as opposed to only erect, axes. 相似文献
86.
The extractability of α-galactosidase activity from mature Vicia faba seeds and the conversion of the low molecular weight form II to the larger oligomer I, was examined over a range of salt concentrations. Specific and total activities of the preparations were high when strong salt solutions were used. Extraction of α-galactosidase I, in comparison with II, requires solutions with a high ionic strength (e.g. 0.5 M NaCl). Interpretation of gel filtration patterns are, however, complicated by conversion of II to I which occurs under these conditions. This conversion is also enhanced by routine procedures used for enzyme purification, such as citric acid precipitation. 相似文献
87.
Henry W. Kircher 《Phytochemistry》1982,21(7):1816-1818
GC of juniper leaf non-saponifiables gave three peaks of sterol-triterpenes which were identified as 10-nonacosanol, sitosterol and a mixture of nonacosanediols. 相似文献
88.
Comparative genetic differences for the phosphoglucomutase and trehalase loci were surveyed in larval and adult blackfly populations of the onchocerciasis vectors Simulium yahense Vajime and Dunbar, and S.sanctipauli Vajime and Dunbar. Genotype frequencies for each stage and all populations were at Hardy-Weinberg equilibrium, indicating that S.yahense and S.sanctipauli remain genetically distinct. S.yahense populations from three different locations were found to be genotypically comparable. The larval population of S.yahense found in closest proximity to a S.sanctipauli population was found to express the phosphoglucomutase allele 1.33, characteristic of S.sanctipauli, with significantly greater frequency than other larval populations of S.yahense. This may constitute evidence of limited genetic introgression of S.sanctipauli with the S.yahense population. 相似文献
89.
Focal contacts of spreading platelets with the substratum 总被引:1,自引:0,他引:1
Contacts with glass substratum formed by the spreading rabbit platelets were examined by an antibody-exclusion method; monoclonal antibodies against 80 kD bovine serum protein were used. It was found that platelets form focal contacts in the course of spreading. The size of the largest focal contacts formed by platelets is smaller than that of the contacts formed by fibroblasts. The antibody-exclusion method revealed focal contacts of platelets much more clearly than interference reflection microscopy (IRM). The similarity of reactions involved in spreading platelets and of large nucleus-containing tissue cells is discussed. 相似文献
90.