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21.
Oka Kotaro; Ikeshima Hiroko; Ishikawa Hideo; Ohta Eiji; Sakata Makoto 《Plant & cell physiology》1988,29(5):771-775
We showed that the surface charge density of protoplasts canbe estimated by the 9-aminoacridine method. The estimated surfacecharge density of the protoplasts isolated from elongating regionsof Vigna mungo root was 39 ? 8 mC/m2. The negative surfacecharge density increased when protoplasts were treated withglutaraldehyde or when EDTA was added to the protoplast suspensionmedium. These results support the validity of our estimationof the surface charge density of protoplasts by the 9-aminoacridinemethod. The concentration of amino groups at the surface ofthe protoplasts was estimated to be 34 mC/m2. (Received June 19, 1987; Accepted April 11, 1988) 相似文献
22.
The molybdenum-iron component of nitrogenase (Mo-Fe component)was purified from soybean nodule bacteroids and antibody wasraised against it in rabbits. Antibody raised against the 53kDa polypeptide which was the major protein in the Mo-Fe componentfraction of soybean nitrogenase was confirmed to be specificto the nitrogenase by immunodiffusion and immunotitration. Thenitrogenase from root nodules of Elaeagnus pungens cross-reactedwith the antibody and appeared from the results of the immunodiffusionto be partially identical to soybean nitrogenase. Using the antibody, we examined intracellular localization ofnitrogenase in root nodules of Elaeagnus pungens, in which Frankiais present as a symbiont, by immuno-gold labelling. Thin sectionsof nodules of Elaeagnus pungens were first treated with anti-nitrogenasespecific antibody and then with colloidal gold-protein A asa marker. The gold particles were observed to be concentratedin the vesicles of the endophyte Frankia. This provides strongsupport for the existence E of nitrogenase in the vesicles.Furthermore, our results suggested that nitrogenase localizesin the hyphae of the endophyte Frankia in Elaeagnus pungensnodules.
1Present address: Iwata Experiment Station, Japan Tobacco Inc.,Iwata-gun, Shizuoka 438, Japan. (Received March 9, 1988; Accepted July 28, 1988) 相似文献
23.
Shin-Ichi Hayama Rika Akamatsu Mayumi Kishimoto Masatsugu Suzuki Hideo Nigi 《Primates; journal of primatology》1988,29(3):423-426
Diverticular disease of the colon was detected in a female Japanese monkey by X-ray examination. The monkey was 15 years old
and had been kept under captive conditions for nine years. Lack of appetite and activity, and constipation were observed.
The monkey was given fiber-rich vegetables and wild plants, and its appetite and activity then improved. Based on a consideration
of various factors, it is suggested that one possible cause of the diverticulosis in this case was a low dietary fiber intake. 相似文献
24.
Direct detection of circulating free radicals in the rat using electron spin resonance spectrometry.
We developed a new technique for directly observing in vivo free radical formation in the circulating blood of living rats using electron spin resonance (ESR) spectrometry without any labeling or trapping agents. It was found that a doublet peak spectrum was obtained following ferric citrate and ascorbic acid injection. The signals were confirmed in different ways to be due to ascorbic acid radicals. These results provide evidence to support the involvement of free radical intermediates in iron-ascorbic acid reactions, and further confirm the suggested mechanisms of both the adverse and protective effects of ascorbic acid in biological systems. Furthermore, this method of direct observation is a new application of ESR spectrometry to living animals. 相似文献
25.
Effects of microsite light availability on the growth and survival of transplantedQuercus serrata Thunb. seedlings in aMiscanthus sinensis Anderss. grass canopy were investigated by a “plant's eye view” approach. Diffuse site factors, i.e., the fractional transmissions
of diffuse photosynthetic photon flux density, were estimated at 15 cm aboveground in 108 microsites where the seedlings grew.
Microsite diffuse site factors were significantly different between surviving and dead seedlings during the experiment period
from April to October (F[1,14]=10.9, P<0.01). Relative growth rate of dry weight for individual seedlings positively depended on the diffuse site factors
(r2=0.482, P<0.001 in May; r2=0.312, P<0.001 in October). Only 16 seedlings produced their second stem flush within the grass canopy. The ratio of height
to dry weight of the second stem flush was significantly higher for the seedlings grew in shady microsites than for those
in less shady microsites (r2=0,471, P<0.01 in May). This study suggests that the microsite heterogeneity of light availability is one of the important
factors affecting the establishment of tree seedlings in patchy grasslands. 相似文献
26.
27.
Summary The catalytic activities of -chymotrypsin, subtilisin Carlsberg, and subtilisin BPN' for hydrolysis of amino acid esters in acetonitrile-water were unusually dependent on the solvent composition. The products obtained as precipitates in high concentrations of acetonitrile were L-amino acids of high optical purities, and effective optical resolution of amino acids was achieved. 相似文献
28.
Terhi Siimes Mikio Nakajima Hideo Yada Hajime Asama Teruyuki Nagamune Pekka Linko Isao Endo 《Biotechnology Techniques》1992,6(5):385-390
Summary A knowledge based system has been shown to be a powerful tool for diagnosing microbial activities during a fermentation process.
Knowledge about lactic acid fermentation was collected by an experimental study ofLactobacillus casei. The effects of the inoculum properties and sterilization time on the cultivation were expressed in a form of a fuzzy rule-based
knowledge network. The system was able to detect abnormal inoculum or sterilization conditions which caused malfunctions in
the cultivations. 相似文献
29.
Cytogenetic examination of four Japanese hagfish species belonging to the order Myxinida (Eptatretus okinoseanus, E. burgeri. Paramyxine atami, and Myxine garmani) revealed differences in chromosome number between germ cells (spermatocytes and spermatogonia) and somatic cells (liver, blood, gill, and kidney). The differences in chromosome number between spermatogonia (54, 52, 48, and 16) and somatic cells (34, 36, 34, and 14) were 20, 16, 14, and 2 in E. okinoseanus, E. burgeri, P. atami, and M. garmani, respectively. The amount of DNA in a somatic cell (2C) relative to that in a germ cell (2C) averaged 54.6% (E. okinoseanus type A), 44.9% (E. okinoseanus type B), 79.1% (E. burgeri), 60.0% (P. atami), and 70.2% (M. garmani). These results clearly indicate that chromosome elimination takes place during early cleavage in the four hagfish species of Myxinida living in Japanese waters, except in the ancestral germline cells. C-banding of metaphase chromosome preparations of germline and somatic cells from each hagfish species revealed that the C-band-positive chromatin in the ancestral somatic cells had been almost completely eliminated. Three patterns of elimination of this chromatin are discussed. 相似文献
30.
A new class mutation of low density lipoprotein receptor with altered carbohydrate chains 总被引:1,自引:0,他引:1
S Shite T Seguchi T Yoshida K Kohno M Ono M Kuwano 《The Journal of biological chemistry》1988,263(36):19286-19289
In a monensin-resistant mutant (Monr-31) of Chinese hamster ovary cells, the O-linked sugar chains of the low density lipoprotein (LDL) receptor are altered, suggesting a mutation at a Golgi apparatus gene. In a compactin-resistant mutant (MF-2) of Chinese hamster V79 cells, the mature LDL receptor is apparently 5000 daltons smaller; the difference is due to altered glycosylation of O-linked sugar chains. Hybrids between MF-2 and Monr-31 still produced LDL receptor molecules with aberrant sugar chains; thus both mutants are in the same complementation group. Krieger and his colleagues (Krieger, M., Kingsley, D., Sege, R., Hobbie, L., and Kozarsky, K. (1985) Trends. Biochem. Sci. 10, 447-452) have classified Chinese hamster ovary cell mutants with altered LDL receptor structure into four groups: ldlA, ldlB, ldlC, and ldlD. Cell-cell hybrids between their ldl mutants and Monr-31 produced wild type mature LDL receptors with normal molecular sizes, suggesting that these compactin- and monensin-resistant mutants define a new class of LDL receptor mutant. Since both of our mutants are defective in internalization of LDL, we assign them as int mutants. This may imply a further etiology for hypercholesterolemia, and cases can now be examined for such a class. 相似文献