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21.
22.
以谷胱甘肽为电子供体的细胞膜氧化还原系统 总被引:1,自引:0,他引:1
内载谷胱甘肽(GSH)的大豆(Glycine max L.)下胚轴正向型质膜囊泡具有以GSH为电子供体的跨膜电子传递活性,能还原膜外电子受体FeCN和细胞色素(Cyt)C,其还原速率分别为(21.6±0.6)nmolFeCN·min~(-1)·mg~(-1)蛋白和(6.6±1.0)nmol Cyt C·min~(-1)·mg~(-1)蛋白。这种跨膜电子传递能引起膜上Cyt P-450吸收光谱标志带(Soret带)的变化,表明Cyt P-450参与了这一氧化还原过程。在跨质膜电子传递的同时伴随着H~ 运输和膜电位的改变。 相似文献
23.
Microculture of single protoplasts of Brassica napus 总被引:1,自引:0,他引:1
Protoplasts of Brassica napus L. were cultured individually in a microdroplet system using a synthetic medium with survival rates of more than 70% and division frequencies of up to 65%. Microcallus formation occurred at frequencies of up to 50%. Factors affecting the survival and division of individually cultured protoplasts, such as composition and volume of culture medium, pH, buffering system, osmolarity and genotype, were analyzed. 相似文献
24.
邱全胜 《Acta Botanica Sinica》1999,41(9):962-966
以大豆( Glycine max L.) 下胚轴为材料, 采用二相法制得高纯度质膜微囊。实验发现,K+ 对质膜H+_ATPase水解活力和转运活力刺激差别显著,对转运活力刺激850% , 对水解活力仅刺激28 .2% 。动力学结果表明,有K+时ATP水解的Km 值为0.70 mmol/L,Vmax 为344 .8 nmol Pi·mg-1 protein·min-1 ; 无K+ 时ATP水解的Km 值为1 .14mmol/L, Vmax为285.7 nmol Pi·mg-1 protein·min-1 。K+ 对ATP水解的最适pH 值也有影响,有K+ 时为6 .5 ,无K+ 时降低到6.0 。进一步实验发现,K+ 对羟胺和钒酸钠的抑制作用影响较大,K+ 可以提高质膜H+_ATPase 对羟胺和钒酸钠的敏感性。结果表明,K+ 可以调节大豆下胚轴质膜H+_ATPase 水解与转运活力之间的偶联程度 相似文献
25.
Elmar Hartmann 《Phytochemistry》1979,18(10):1643-1646
The labelling of acetylcholine was investigated in bean seedlings (Phaseolus vulgaris) and hypocotyl hooks. Labelling could only be found after red light irradiation but not in the dark. Acetate was a much better precursor than choline. Glucose gave no detectable amounts of acetylcholine labelling during 24 hr of incubation. The rate of acetylcholine labelling was higher in whole seedlings than in hypocotyl hook preparations. 相似文献
26.
Baumgartner, N. and Fondeville, J. C. 1989. Photocontrol of the hypocotyl hook opening of Sinapis alba seedlings. Involvement of phytochrome and a high irradiance response.
A statistical evaluation of the hypocotyl hook opening (hook opening index) was used for measurement of the hook angle in lots of etiolated Sinapis alba L. cv. Albatros seedlings. Studies of the kinetics for hook opening were carried out in continuous fluorescent white, blue and red light (6, 15 and 40 μmol m-2 s-1 ) with 2-day-old dark-grown seedlings. At the beginning of the irradiation period the photoresponse in red light was the opposite to that in blue (low photon fluences). Blue rapidly induced the hook opening (in less than 20 min), while red produced hook tightening (photon fluences up to 70 mmol m-2 ), which precedes the normal progressive hook opening. For low fluences, the data were consistent with the involvement of phytochrome and a specific blue light photoreceptor. A phytochrome effect was observed in the hook opening, dependent upon a high irradiance response (HIR). This HIR (like that for the inhibition of the hypocotyl elongation) was characterized by a wavelength response curve with maxima in the blue and far-red regions of the spectrum. 相似文献
A statistical evaluation of the hypocotyl hook opening (hook opening index) was used for measurement of the hook angle in lots of etiolated Sinapis alba L. cv. Albatros seedlings. Studies of the kinetics for hook opening were carried out in continuous fluorescent white, blue and red light (6, 15 and 40 μmol m
27.
Using a physicochemical method, the distribution of endogenous indole-3-acetic acid (IAA) was measured in the peripheral and central cell layers, as well as in the illuminated and shaded sides of phototropically stimulated radish hypocotyls (Raphanus sativus var. hortensis f. gigantissimus Makino). The IAA was evenly distributed over the illuminated and shaded sides in the first and second positive phototropic curvatures induced by a pulse or a continuous unilateral illumination with blue light. Also, no net exchange of the IAA between the peripheral and central cell layers was observed during these curvatures. These results suggest that phototropism of radish hypocotyls cannot be described by the Cholodny-Went theory. 相似文献
28.
结球甘蓝离体下胚轴愈伤组织的维管组织及管状分子 总被引:4,自引:0,他引:4
结球甘蓝离体下胚轴培养初期,在切口较深层发现的维管组织结节,是由外植体维管组织衍化的。愈伤维管组织既可由愈伤薄壁细胞分化,也可由愈伤形成层分化。愈伤形成层向内分化导管分子,向外没有发现筛分子的分化。愈伤维管组织有不同的形态,起初常各不相连,后和外植体维管组织衔接。芽的再生起初和愈伤维管组织没有直接的联系,后原形成层自上而下分化,逐渐与愈伤维管组织相连接。不定根发生于维管组织结节的单向极性分化,始终 相似文献
29.
A system for somatic embryogenesis and plant regeneration of spinach from hypocotyl segments has been established. Callus
was induced on solid media supplemented with 8.5–15.0 mg.l−1 of indole-3-acetic acid and 3.46–34.64 mg.l−1 gibberellic acid. Callus was then subcultured on different media (solid or liquid) with or without IAA, or continuously maintained
on the initiating media. Somatic embryos were obtained in subcultures on IAA-containing media as well as in long-term cultures
on initiating media. The best results were achieved in liquid subcultures. About 60% of plantlets survived after transplanting
in pots. 相似文献
30.
为了将外源基因导入花椰菜原生质体获得转基因植株,本文研究了PEG介导的外源基因在花椰菜下胚轴原生质体中的瞬间表达。(1)20%PEG将质粒pBI221导入原生质体后GUS表达比13%PEG导入的高,但易造成原生质体损伤。(2)热激处理增强表达,但在随后的培养过程中易造成原生质体降解。(3)原生质体状况对表达有重要影响,5d龄下胚轴原生质体比8d龄的表达强。(4)不同质粒及启动子表达强度不同。质粒pKIWI101比pBI221表达强3倍左右。 相似文献