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41.
42.
Formation of protoplasts and their reversion were followed in 7 strains of brevibacteria. The formation of protoplasts and
their reversion differed both between various species of brevibacteria and between various mutant strains of the same species. 相似文献
43.
Myosin content and phosphorus (P) concentration of myosin preparations were measured in non-pregnant and pregnant human myometrial tissue specimens. It was found that the amount of myosin gained from 1 g of minced myometrial tissue is 0.5 mg in the early follicular phase of the menstrual cycle, 0.6-0.7 mg in the late luteal phase, and 6-7 mg during pregnancy. Considering the different functional stages of the myosin sources and the performance characteristics of the methods, the estimated myosin content of non-pregnant myometrium is 1.0-1.5 mg, while 10-15 mg in pregnant myometrial tissue. A considerable amount of P is bound to the preparations. It is the smallest in the post-menstrual period and increases towards the end of the cycle. The largest amount of P is gained from fresh pregnant uterine samples. Analysis of the alkaline hydrolysate showed that the phosphate group was bound to amino acids, in the largest amount to arginine, less to histidine and the smallest amount to lysine and serine. As a function of the duration of storage, especially the P-Arg concentration was decreasing. The prolonged hydrolysis time decreases again the concentration of P-Arg with a consecutive increase of No. 1 and 2 P-containing peaks in the chromatographic profile of alkaline hydrolysate. 相似文献
44.
The aerobic adaptation of anaerobically grownP. denitrificans carried out under conditions of limited growth is characterized by an exponential decrease of nitrite reductase activity and a sharp increase of cytochrome oxidase and a slow increase of NADH:cytochromec oxidase reductase and succinate dehydrogenase activities. The adaptation in a minimal adaptation medium under conditions of active or blocked protein synthesis showed that in addition to the degradation component of turnover during the aerobic adaptation other degradation enzyme(s), whose synthesis is induced by oxygen, are involved. This degradation system plays an essential role in the rapid disappearance of nitrite reductase and a pronounced decrease of the membranebound cytochromec oxidase activities during aerobic adaptation in the minimal adaptation medium. 相似文献
45.
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47.
Ultrathin sections were prepared from the tissues of lettuce leaves with mosaic-like symptoms and thickened nervature which were studied by means of electron microscopy. Intracellular inclusions surrounded by a membrane were found in the cytoplasm of parenchym cells of the investigated lettuce leaves(Lactuca saliva L. provar.capitata L. nid.jaggeri Helm., cv. Pra?an). Crystals with a distinctly apparent hexagonal lattice could be observed in the inclusions. No crystal containing inclusions were found in the tissues from the leaves without mosaic-like symptoms and in those from thickened nervature. 相似文献
48.
In the pea test a highly positive response to the treatment with IAA reversed to a negative one or became 5 to 6 times weaker when CCC was applied together with IAA. In cultivating pea seedlings, following their decapitation, for two days in a 0.25 per cent CCC solution and then in water, growth of their cotyledonous axillaries (cotylaries) were inhibited. This inhibitive action of CCC could be made ineffective when the seedlings, following two-days’ cultivation in the CCC solution, were grown further in kinetin solutions (0.37–3 mg per 1). Cotylaries of decapitated pea seedlings, when grown in kinetin solutions were inhibited. With kinetin solutions of 6–12 mg/l a strong inhibition also occured in the growth of roots at the apical parts of which spherical swellings were developing. The CCC supplied to the roots of intact etiolated pea seedlings is translocated acropetally into the stem at a rate of about 5 cm per hour. Decapitation of the plant causes retardation of this transport, yet a coat of 0.00001–1% IAA or kinetin paste produces acceleration of the stream. Existence of an antagonism between CCC and IAA, demonstrated earlier, was found holding true also for B-9 (N, N-dimethyl-aminesuccinamic acid) and IAA, as the inhibitive action of B-9, 0.06% solution on the growth of lettuce hypocotyls was reduced to a highly significant degree when the plants were supplied with B-9 together with IAA at a concentration of 10 mg/l. 相似文献
49.
We compared the occurrence of peroxidase isozymes in protein extract from roots, hypocotyls and cotyledons of 10 dayCucurbita pepo plants and of adult leaves of older plants by means of starch gel and polyacryl amide gel electrophoresis. We reached maximum discrimination by means of starch gel electrophoresis: 11 zones were ascertained on the cathode side and about 2 on the anode side at pH 3.1. Two zones occurred regularly:A and (the latter having a more complicated structure). ZoneD is characteristic for roots, but is it suppressed and seldom found with leaves. On the other hand zonesC 1 andC 2 are clearly discernible with leaves but are substantially less evident with roots. The character of anodic zoneZ is discussed later in this paper. 相似文献