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1.
Helga Drumm  Hans Mohr 《Planta》1966,72(3):232-246
Zusammenfassung In einer früheren Arbeit wurde gezeigt (Ohlenroth und Mohr, 1963), daß sich die Vorkeime von Dryopteris filix-mas im Blaulicht zu normalen zweidimensionalen Prothallien mit einem relativ hohen Proteingehalt entwickeln. Im Hellrot hingegen bilden sich Zellfäden (= Protonemen) aus, deren Proteingehalt bei gleicher Photosyntheseleistung wesentlich geringer ist.In der vorliegenden Arbeit wird gezeigt, daß auch der RNS-Gehalt im Blaulicht stets größer als im Hellrot ist. Die blaulichtabhängige RNS-Zunahme setzt zeitlich früher ein als die Proteinzunahme.In Umsetzexperimenten von Hellrot nach Blau manifestiert sich die morphogenetische Umsteuerung der Protonemen zeitlich eher als die blaulichtabhängige Steigerung des Proteingehalts. Kasemir und Mohr (1965) konnten zeigen, daß es sich bei dem Blaulichtprotein in erster Linie um eine Vermehrung des Strukturproteins der Chloroplasten hanhandelt. Die blaulichtabhängige RNS-Zunahme dagegen ist spätestens zum Zeitpunkt der morphologischen Umsteuerung faßbar. Dieses Ergebnis wird dadurch gestützt, daß Blaulicht im Vergleich zu Hellrot rasch einen gesteigerten Einbau von 14C, als 14C-Uridin (U) geboten, in die RNS-Fraktion verursacht. Das Blaulicht scheint in den Farnvorkeimen zwei verschiedene Vorgänge zu verursachen. 1. Steigerung einer autonomen Proteinsynthese in den Chloroplasten. 2. Auslösung oder Steigerung einer spezifischen Enzymsynthese im Cytoplasma. Die blaulichtabhängige Steigerung der RNS-Synthese scheint damit in Zusammenhang zu stehen. Die Daten der vorliegenden Arbeit werden als Indizien dafür angesehen, daß das Blaulicht seine morphogenetische Wirkung über eine differentielle Genaktivierung ausübt.
The regulation of RNA synthesis in fern gametophytes by light
Summary Morphogenesis and metabolism of the gametophytes (= sporelings) of the common male fern Dryopteris filix-mas are controlled by visible radiation. Short wavelengths visible radiation (= blue light) leads to an increase in protein synthesis and makes possible the formation of normal two-dimensional prothallia. Under long wavelengths visible radiation (= red light) the sporelings grow as cellular filaments the protein contents of which are markedly lower than under blue irradiation even under conditions of equal rate of dry matter accumulation in red and blue (Ohlenroth and Mohr, 1963). — It is shown in the present paper that the RNA content of sporelings of the same age is always higher in blue light than in red light (Figs. 1, 3). The blue-dependent increase of RNA occurs faster than the blue-dependent increase of protein (Fig. 2). Furthermore the increase of protein per sporeling is much larger than the increase of RNA (Fig. 4). These facts are in agreement with the hypothesis that in some way or another blue light initiates differential gene activation.The blue light-dependent morphological changes which occur if we put red grown filamentous sporelings under blue light can be measured much faster than the blue light-dependent increase of the bulk protein (Figs. 5, 6). We have to conclude as we did in a previous paper (Kasemir and Mohr, 1965) that the blue light-dependent increase in the protein content of the sporelings might be mainly due to an increase of chloroplast protein. — The blue light-dependent increase of the RNA content occurs at least as fast as the morphological changes (Figs. 5, 6). This finding is supplemented by the observation (Fig. 8) that blue light markedly and rapidly stimulates the incorporation of 14C into RNA. The 14C was applied as 14C-uridine (U). — It seems that blue light causes an increase of protein synthesis in the chloroplasts as well as in the cytoplasm. Blue light-dependent RNA synthesis seems to be involved in this response. These data support the view that blue light might exert its morphogenetic control through differential gene activation.


Die Arbeit wurde durch Sachbeihilfen der Deutschen Forschunggemeinschaft und der Stiftung Volkswagenwerk gefördert.  相似文献   

2.
Zusammenfassung Bei der quantitativen Analyse der Protein-Aminosäuren von Farnvorkeimen (Dryopteris filix-mas) ergab sich, daß die Steigerung des Proteingehalts durch Blaulicht mit einer Zunahme aller untersuchten Aminosäuren einhergeht. Dabei bleibt der prozentuale Anteil der einzelnen Aminosäuren am Gesamtprotein immer annähernd gleich, abgesehen vom Prolin. — Offenbar kommt es unter dem Einfluß von Blaulicht hauptsächlich zu einer quantitativen Vermehrung und nur im geringen Maße zu einer qualitativen Veränderung der Proteinfraktion. — Da die pools der erfaßbaren freien Aminosäuren im Hellrot stets größer sind als im Blaulicht, ist der Schluß berechtigt, daß das Blaulicht seine Wirkung im Zusammenhang mit der Polypeptidsynthese und nicht über eine Steigerung der Aminosäuresynthese ausübt.
An analysis of the blue light mediated increase of protein synthesis in fern gametophytes on the level of amino acids
Summary Morphogenesis and metabolism of the sporelings (= young gametophytes) of the common male fern Dryopteris filix-max are controlled by visible radiation. Short wavelengths visible radiation (= blue light) leads to an increase in protein synthesis and makes possible the formation of normal two-dimensional prothallia. Under long wavelengths visible radiation (= red light) the sporelings grow as cellular filaments, the protein contents of which are markedly lower than under blue light even under conditions of equal rate of dry matter accumulation in red and blue light (Fig. 2). — Quantitative amino acid analysis of the total protein of blue and red grown sporelings did not reveal any striking difference. The contents of all those amino acids which can be measured quantitatively after protein hydrolysis show about the same increase under the influence of blue light (Figs. 3, 4). Only in the case of proline are the differences between red grown and blue grown sporelings indicative of a qualitative change in the nature of the protein fraction (Fig. 3/h). —The pools of the free amino acids are always smaller in blue grown sporelings than in red grown ones (Figs. 6, 7). — The facts reported in this paper indicate that blue light leads mainly to a quantitative increase in the rate of protein synthesis. The influence of blue light on the qualitative nature of the protein fraction seems to be slight. On the other hand, the data on the pool sizes of the free amino acids support the conclusion that blue light controls the rate of protein synthesis at the stage of polypeptide synthesis and not through amino acid synthesis.
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3.
Rainer Bergfeld 《Planta》1968,81(3):274-279
Summary Morphogenesis and differentiation of the young gametophytes (=sporelings) of Dryopteris filix-mas are controlled by light. Blue light leads to the formation of normal two-dimensional prothallia; under red light, however, the gametophytes grow as cellular filaments. Morphogenesis in blue light is connected with an increase in protein synthesis; in red light the protein content of the sporelings is markedly lower. The size of the chloroplasts is correlated with the protein content of the sporelings.In the present paper the diverse effect of chloramphenicol (CAP) and actidione (cycloheximide, ACT) was studied in connection with the formation of chloroplasts. ACT blocks the growth of the gametophytes, while the chloroplasts remain functional. On the other hand, CAP does not influence morphogenesis of the gametophytes. In particular the activity of the dividing apical cells remains untouched. Even when the light quality is changed during the development the corresponding specific effect of the light quality on morphogenesis is normal. The chloroplasts, however, become smaller, probably by inhibition of synthesis of structural proteins. But their synthetic activity is not completely suppressed. The specific blue or red light dependent morphogenesis is not changed, when protein synthesis in the chloroplasts is inhibited.  相似文献   

4.
H. D. Payer  H. Mohr 《Planta》1969,86(3):286-294
Summary Morphogenesis and metabolism of the early gametophytes (=sporelings) of the common male fern are controlled by light. The normal two-dimensional development of the gametophytes takes place only in white or blue light; in red light alone, on the other hand, the sporelings remain filamentous even under conditions of equal photosynthetic rate.The problem has been whether blue light exerts its morphogenic influence through differential gene activation. In other words: does blue light mediate the synthesis of morphogenic enzymes which are required for normal morphogenesis. In an earlier paper (Drumm and Mohr, 1967) we have shown that blue light increases the rate of RNA synthesis within an hour whereas the first indication of a morphogenic change due to blue light is only discernible about 3 hours after the onset of blue light (Figs. 1,2). Furthermore we have shown (Mohr, 1965) that Actinomycin D specifically inhibits the blue light mediated morphogenic alterations, and Bergfeld (1967) has shown that blue light will rapidly lead to changes in nuclei and nucleoli in the fern sporelings. In the present paper it has been shown that blue light does increase the rate of protein synthesis about an hour after the transfer of the sporelings from the red into the blue light of equal quantum flux density (350 pE·cm-2·s-1).The rate of protein synthesis was measured in shortterm experiments (40min) using 14CO2. The photosynthetic rate was the same in red and blue; it was not influenced by the transfer(Fig. 3). Likewise the rate of 14C incorporation into the pool of free amino acids was not significantly different in red and blue light (Fig.4). On the other hand, the rate of incorporation of 14C into the protein increased rapidly after the transfer of the sporelings from the red into the blue light (Fig. 5). The same phenomenon (no influence of blue light on the specific activity of the free amino acid; a strong promotive influence on the specific activity of the protein-bound amino acid) was observed in the case of alanine which was investigated in detail (Figs. 6, 7). Since the increase of the protein content of the sporelings is not significant during the first six hours after transfer to blue light (Fig. 8) the protein induced by blue light and directly related to morphogenesis can only be a very small fraction of the total protein of the sporeling.The data strongly support the hypothesis (Ohlenroth and Mohr, 1964), that the morphogenic effect of blue light on the fern sporelings is due to the induction of morphogenic enzymes by blue light.  相似文献   

5.
H. D. Payer 《Planta》1969,86(2):103-115
Summary In fern gametophytes (= sporelings) there is a strong correlation between the degree of blue light mediated photomorphogenesis and the protein content of the organism (cf. Mohr, 1963). In a previous paper (Payer et al., 1969) we have shown that blue light specifically increases the rate of protein synthesis in the fern sporelings over the rate which is maintained under red light. — In the present paper blue light mediated protein synthesis has been dealt with further using one representative amino acid, alanine, which was labelled with 14C from 14CO2 under steady state conditions of photosynthetic 14C incorporation under blue or red light.Synthesis of free alanine is proportional to the rate of photosynthesis (Table 1). For a number of reasons we conclude that alanine is derived directly from primary photosynthetic products. Since the pool size of the thoroughly 14C-labelled pool of free alanine is much less than the actual, pool size of this amino acid, (Table 1), and since the specific activity of the isolated 14C-alanine is much below the value we can expect on the basis of the specific activity of the 14CO2 applied we conclude that there are separate pools of free alanine; active (with respect to protein synthesis) and inactive pools which do not mingle. Taking into account this possibility of compartmentation of pools of free amino acids we have calculated in the case of 14C-alanine the rate of protein synthesis for two extreme instances (Table 2). A comparison of the theoretical values with the actual data indicates that indeed protein synthesis is fed from active pools of amino acids while the inactive pools are possibly located in the vacuoles. The total pool of alanine is much larger in red grown than in blue grown sporelings while the active pools seem to have the same size under both conditions. The cells of the red grown sporelings have much larger vacuoles than the cells of the blue grown sporelings.The rate of protein synthesis is under our conditions 1.8 times higher in blue light than in red light. The rate of turnover of the total protein is 0.29% per hour in the blue and 0.23% in the red light. The absolute turnover of protein is 1.5 times higher in blue light than in red light. It is concluded that the blue light mediated increase of protein synthesis is very real. Blue light must act specifically at the level of polypeptide synthesis.  相似文献   

6.
Mohr  H.  Ohlenroth  K. 《Planta》1962,57(6):656-664
Summary Under conditions of identical rate of photosynthesis (measured by dry weight increase under steady state conditions) growth and differentiation of the gametophytes of ferns (e.g.Dryopteris filix-mas) are completely different in red and blue light. In the blue light normal growth and morphogenesis take place and normal two or three-dimensional prothallia are formed (Fig. 3). In the red, however, the prothallia look very similar to those growing in complete darkness: they grow as one-dimensional filaments (Fig. 1).It has been shown in this paper that photosynthesis, which is important as a source of organic material and free energy, has no influence at all on morphogenesis. Morphogenesis, i.e. the formation of normal prothallia instead of filaments, is controlled by a photoreactive system which depends on blue light of suitable intensity and which is not related to photosynthesis as such. If no blue light is present no morphogenesis occurs in spite of high photosynthetic activity.In our opinion theprimary products of photosynthesis are the same in all wavelengths. But now the photomorphogenic light reaction which depends on blue light apparently directs the flow of metabolites. In this way even the same initial products of CO2 fixation may lead subsequently to rather different photosynthetic products and consequently to the very great difference between prothallia growing with or without blue light.The addition of sucrose has practically no influence on growth and morphogenesis under our conditions. On the basis of our results we cannot agree with the general conclusions drawn byMiller andMiller (1961) who regard photosynthesis as a photomorphogenetic system in these gametophytes of ferns.Mit 6 Textabbildungen.Herrn Professor Dr.E. G. Pringsheim in Verehrung zum 80. Geburtstag.  相似文献   

7.
H. D. Payer  U. Sotriffer  H. Mohr 《Planta》1969,85(3):270-283
Summary Morphogenesis and metabolism of the early gametophytes (= sporelings) of the common male fern are controlled by light. The normal two-dimensional development of the gametophytes in white or blue light is correlated with an increase in protein content; inred light alone, on the other hand, the sporelings remain filamentous, and the protein content is markedly lower (cf. Mohr, 1965). The problem has been whether blue light increases the rate of protein synthesis or decreases the rate of protein degradation. This problem was solved in the present paper by the use of 14CO2. Blue light promotes specifically the rate of protein synthesis as indicated by the increase of 14C incorporation into protein-bound amino acids under blue light as compared with red light.Using 14CO2 we have analyzed the kinetics of free amino acid synthesis (Fig. 4) and protein synthesis (Fig. 5) under steady state conditions of photosynthetic CO2 incorporation in blue or red light (Fig. 3). Under our conditions the rate of photosynthesis is about 1.5 times higher under blue light than under red light (Fig. 3, Table 1).The facts that the total pool sizes of the free amino acids are smaller in blue than in red light (v. Deimling and Mohr, 1967; Table 2) and that, on the other hand, the 14C-contents of the thoroughly labelled amino acid pools are virtually identical in blue and red (Table 3) indicate (a) that the pool sizes of these labelled amino acids may be equal in both light qualities and (b) that there is a compartmentation of free amino acid pools in the fern sporeling. This problem will be dealt with more in detail in a forthcoming paper on the behaviour of alanine in the fern sporeling (Payer, 1969).Protein synthesis is obviously much stronger under blue light than under red light. The detailed kinetics (Fig. 5b) indicate the involvement of two sorts of proteins: a relatively small part with high turnover which is rapidly labelled with a small but significant difference in red and blue, and a larger part with a slower turnover, the synthesis of which is strongly favored by blue light. — The first sort could be enzyme protein; the latter sort might be structural protein of the chloroplasts. These organelles increase dramaticly in size under the influence of blue light (Bergfeld, 1963). The amino acid composition of the protein, however, does not show any qualitative difference in gametophytes grown in blue or red light (v. Deimling and Mohr, 1967, Table 4).
Die Aufnahme von 14CO2 und die Verteilung des 14C auf freie Aminosäuren und auf Proteinaminosäuren im Hellrot und im Blaulicht. [Objekt: Farnvorkeime von Dryopteris filix-mas (L.) Schott]
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8.
S. M. Assmann 《Oecologia》1992,92(2):188-195
Summary The effects on plant growth and stomatal physiology of alterations in light quantity and quality during development were investigated in the C3 monocot, Commelina communis. Reduction in light intensity resulted in decreased branching and stem elongation, with effects more severe under neutral shade (R:FR1.0) than under leaf shade (R:FR0.4) conditions. Shade treatments had no effect on the leaf area or stomatal density of newly expanded leaves. Gas exchange measurements on leaves that had expanded under the different treatments indicated that a reduction in light intensity decreased the magnitude and slowed the kinetics of stomatal responses to pulses of blue light, particularly in plants from the neutral shade treatment. These results indicate that the specific stomatal response to blue light is plastic, and is modulated by the light environment prevailing during leaf development.  相似文献   

9.
Summary Dark grown seedlings ofLactuca sativa L. var. Grand Rapids (tip burn resistant strain) do not form an appreciable plumular hook. But a normal plumular hook, as is formed e. g. byPhaseolus vulgaris in complete darkness, can be induced by red light. It has been shown in this paper that the formation of the plumular hook in lettuce seedlings is controlled exclusively by the reversible red far-red reaction system (low energy reaction).The hook which has been closed by red radiation can be reopened by light. In this respect only blue and far-red radiation are effective. The hook can only be reopened if blue or far-red are applied with rather high irradiances over a relatively long time period (high energy reaction). The action spectrum and the kinetics of this high energy reaction show that this photoreaction is identical with the so called blue, far-red reaction system which we could demonstrate during recent years to be involved in the photomorphogenesis of the mustard seedling (Sinapis alba L.) and which apparently is also involved in many other photomorphogenic responses (cf.Hendricks et al. 1960). In mustard the low and the high energy reactions always function in a synergistic manner, in lettuce the opposite is true: The closing of the plumular hook is controlled by the reversible red, far-red system, the reopening of the hook is controlled by the blue, far-red system. In this way the two systems can be more clearly separated and characterized physiologically.

Mit 12 Textabbildungen  相似文献   

10.
Zusammenfassung Der Verlauf des Nahrungsflusses im Darmtrakt der Kleinzikade Euscelidius variegatus wird nach Verfütterung von farbstoffhaltiger Nährlösung ermittelt. Es wird der Beweis erbracht, daß die aufgenommene Nahrungsmenge in der Filterkammer geteilt wird und die beiden Anteile den Darmtrakt auf zwei verschiedenen Wegen in Richtung Rektalblase passieren. Ein Anteil der aufgenommenen Nährlösung wird über einen Kurzschlußweg in der Filterkammer sowohl über den Filterkammerdarm als auch über die Kryptonephridien direkt in den Enddarm gepumpt, während die in der Magentasche der Filterkammer verbleibenden Nahrungsanteile über einen langen Verdauungsweg zum After gelangen. Hierbei wird der Magentascheninhalt in den Magen gedrückt. Von dort aus passiert er den Mitteldarm und erreicht über den Enddarm den After. Der Kurzschlußweg und der Verdauungsweg können gleichzeitig benutzt werden. Der Kurzschlußweg wird von der Nahrung jedoch in viel kürzerer Zeit durchströmt als der längere Verdauungsweg.
The directions of the flow of food in the alimentary trad of the leafhopper Euscelidius variegatus KBM. (Jassidae)
Summary The leafhopper Euscelidius variegatus is fed with synthetic food, coloured with 1% Azorubin-S. Its flow in the alimentary tract has been studied. It has been found that the sucked-in food is divided into two parts in the filter chamber, each taking different way in the alimentary tract for its flow. One part of the food is pumped into the hindgut via the short circuit way going through the filter chamber once over the Filterkammerdarm and also over the kryptonephries. That part of the food, which remains in the pocket of the filter chamber takes the long digestion way to the anus over stomach, midgut and hindgut. Both the ways could be used at the same time. But the food takes much shorter time for its passage through the short circuit way as compared to the time needed for the long digestion way.
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11.
Zusammenfassung 1974–1983 waren in einem mit 600 künstlichen Nisthöhlen ausgestatteten Lärchen-Versuchsforst (52.27 N, 7.15 E) bei Lingen/Emsland beim Trauerschnäpper 20,7% der nachweislich mit einem polygamen verpaart. Neben 51 Bigynie-Fällen konnte auch 4mal Trigynie nachgewiesen werden. mit Polygamie-Nachweis waren im Mittel älter als die übrigen (2,71 bzw. 2,18 Jahre). Polygame hatten im Durchschnitt längere Flügel und ein größeres Gewicht als ohne Polygamie-Nachweis, was als Folge der unterschiedlichen Altersstruktur zu deuten ist. Brutkästen der Bigamisten waren im Mittel 258 m voneinander entfernt (Maximum 750 m). Bei Bruten ohne Nachweis eines fütternden lag die Anzahl ausgeflogener Junge (im Mittel 2,9) gesichert unter dem Bruterfolg von zwei anderen Gruppen (fütterndes bei einer Brut festgestellt 4,7; fütterndes bei 2–3 Bruten festgestellt 4,5). Zwischen den Schlüpfterminen von Bigamisten-Bruten lagen 1–16 Tage. Das Durchschnittsalter der in den jeweils früheren Bruten betrug 2,67, in den jeweils späteren Bruten 1,67 Jahre.
Polygyny in the Pied Flycatcher (Ficedula hypoleuca) at the western border of its Central European range
Summary 1974–1983 in a study area of larch forest (52.27 N, 7.15 E), with 600 nestboxes, near Lingen/Emsland in western Lower Saxony, polygyny among Pied Flycatchers was identified as participation of in feeding at 2 or 3 nestboxes (bigyny or trigyny). 20.7% of were shown to be paired with a polygamous . Beside 51 cases of bigyny 4 cases of trigyny were identified. The incidence of polygyny was also considered in relation to the border situation of the study area. Proven polygamous were on average older than other (2.71 as compared to 2.18 years). On average polygamous had longer wings and greater bodyweight than without polygamous record, which is to be interpreted as a result of differing age structure. On average the mean distance between nestboxes of bigamists was 258 m (max. 750 m). In cases of broods without recorded feeding (generally this would occur in cases of secondary broods of polygamous in which the assisted only rarely or not at all) the number of reared young (on average 2.9) was significantly lower than the breeding success realised by 2 other groups ( recorded as assisting in rearing one brood only 4.7; recorded as assisting in rearing 2–3 broods 4.5). A period of 1–16 days (on average 7) elapsed between the hatching dates of broods of bigamists. The average age of in the earlier broods was 2.67 yrs, in the later broods 1.67 yrs.


Gefördert mit Hilfe von Forschungsmitteln des Landes Niedersachsen.  相似文献   

12.
Zusammenfassung Bei der diploiden hohen Garten-Iris cv. Floridor (Cayeux 1929) wurde als bisher einziger Sorte ein neues Delphinidinglycosid Floridorin aufgefunden. Seine chemische Konstitution wurde als Delphinidin-3-Glukose-Rhamnose-p-Cumarsäure aufgeklärt. Es fand sich zusammen mit dem schon von uns aufgeklärten Anthozyan Tulipanin (Delphinidin-3-Glucose-Rhamnose). Das Hauptanthozyan der anderen Garten-Iris ist das von uns neuerdings nachuntersuchte Violanin. Die Untersuchungen wurden mit bereits von uns angegebenen neueren Methoden ausgeführt, wie der stufenweisen Hydrolyse und dem oxidativen Abbau. Das neue Floridorin zeigte bei den diploiden Garten-Iris einen monohybriden rezessiven Erbgang gegen Violanin. Die Blüten der Sorten, die Floridorin enthalten, sind schon mit dem Auge an einem charakteristischen taubenblauen Farbton zu erkennen.
On the constitution and inheritance of a new delphinidine glycoside Floridorin from the cultivated iris variety cv. Floridor (Cayeux 1929)Studies on anthocyanins LI
Summary The diploid tall bearded garden Iris cv. Floridor (Cayeux 1929) proved to be thus far the only variety with a different anthocyanine, called Floridorin. Its chemical structure has been found to be delphinidine-3-glucose-rhamnose-p-coumaric-acid. It occurs together with tulipanine already analyzed by us as delphinidine-3-glucose-rhamnose. The main anthocyanine of thePogoniris garden varieties proved to be violanin the structure of which has been studied by us lately. The investigations were carried out by some newer methods, such as partial hydrolysis and oxidative degradation already published by us. The new Floridorin gives a monohybrid recessive Mendelian ratio with other diploid varieties ofPogoniris colored by violanine. The varieties colored by Floridorin show a characteristic greyish blue coloration which can be recognized with the naked eye.
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13.
Summary The basal swellings on the processes of the cone cells of Pteronemobius include conspicuous bodies consisting of a double unit membrane as well as of many granules (-glycogen?). These membranes are infoldings of the cell membrane.According to their site these structures seem to be a continuation of the rhabdome to which they lie very close distally. These bodies probably could—like the rhabdome-act as light guides, and together with pigment prevent an intrusion of light into deeper regions of the head.  相似文献   

14.
Zusammenfassung Pantothensäurebedürftige Hefezellen können ihren Bedarf an diesem Vitamin nicht allein aus -Alanin decken, sondern auch aus Benzoyl--Alanin, -Alanyl-d,l-Norleucin und -Alanyl-l-Histidin. Der Antagonist Asparagin hemmt die Verwertung dieser Peptide genauso wie diejenige der freien Aminosäure. Durch höhere Konzentrationen an -Alanin oder -Alanyl-d,l-Norleucin läßt sich die Hemmwirkung nicht allein kompensieren, es kommt sogar zu einer Förderung des Hefewachstums. Der Antagonist wird dann zum Synergisten.
Summary The -alanine containing peptides benzoyl--alanine, -alanyl-d,l-norleucine and -alanyl-l-histidine can substitute for the amino acid -alanine in a pantothenic acid requiring yeast. Asparagine, an antagonist of -alanine, affects these peptides in a similar manner. In combination with an overdose of -alanine or -alanyl-d,l-norleucine, asparagine is no longer an antagonist but becomes a synergist.
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15.
The distribution pattern of total lipids, glyco- and phospholipids, and one betaine lipid (DGTS) in the fronds of the ferns Dryopteris filix-mas and Matteuccia struthiopteris was studied. The lipid composition of the embryo leaflets forming a bud, or treble clef, and that of fully opened leaves changed throughout the growth season. The maximum amount of DGTS in clefs and mature leaves was detected at the beginning of the season. By midsummer, the DGTS content decreased, dropping to zero in the fully opened leaves, and then increased again. The amount of DGTS in the clefs collected in October versus those collected in May was somewhat higher in the case of Dryopteris filix-mas and almost twofold lower in the case of Matteuccia struthiopteris. The ratio between polar lipids contained in the clefs and mature leaves throughout the growth season was determined.  相似文献   

16.
T. H. Attridge  M. Black  V. Gaba 《Planta》1984,162(5):422-426
An interaction is demonstrated between the effects of phytochrome and cryptochrome (the specific blue-light photoreceptor) in the inhibition of hypocotyl elongation of light-grown cucumber (Cucumis sativus L.) cv. Ridge Greenline seedlings. At certain fluence rates of blue light the total inhibition response is greater than the sum of the separate responses to each photoreceptor. The threshold for response to blue light is reduced at least 30-fold by additional red-light irradiation. The synergistic effect is demonstrated for two different fluence rates of red light. Synergism is mediated by phytochrome in both the cotyledons and the hypocotyl.Abbreviations and symbols BL blue light - FR far-red light - Pfr far-red-absorbing form of phytochrome - R red light - photostationary state of phytochrome - c calculated   相似文献   

17.
A novel syrup containing neofructo-oligosaccharides was produced from sucrose (Brix 70) by whole cells of Penicillium citrinum. The efficiency of fructo-oligosaccharides production was more than 55% and those of the main carbohydrate components, 1-kestose (Fruf 21Fruf 21 Glc), nystose (Fruf 21Fruf 21 Fruf 21 Glc) and neokestose (Fruf 26 Glc12 Fruf), were 22, 14 and 11%, respectively.  相似文献   

18.
On age morphological changes of males of Chydoridae (Cladocera)   总被引:2,自引:2,他引:0  
N. N. Smirnov 《Hydrobiologia》1967,30(3-4):555-571
Summary Young and adult males of 11 species of Chydoridae are studied, their figures being published here (fig. 1–15). The necessity is stressed to distinguish young forms of males and gynandromorphic individuals.Pleuroxus balatonicus is considered to be described from the population ofPleuroxus unicatus having under Balaton Lake conditions retarded transformation of young males into adult form, and accordingly having unusually numerous young males. \qO\qs\qn\qo\qv\qn\qy\ye \qr\ye\qz\qu\ql\Qj\qt\qa\qt\qy 11 (. 1–15). . , Pleuroxus uncinatus , Pleuroxus balatonicus.  相似文献   

19.
Feulgen and silver-stained karyotypes and meiosis of two triploid viviparous onion forms (Allium cepa var.viviparum), the Croatian Ljutika and the Indian Pran, were comparatively analyzed. The results of chromosome measurements show that Ljutika and Pran are karyologically not identical, although significant similarities were found in the morphology of their chromosomes. Five geographically distant clones of Ljutika showed good agreement in the number and gross morphology of the chromosomes and in the number and position of NORs and interphase nucleoli. Heterotrivalents were predominant in meiosis of Ljutika but a relatively high frequency of higher multivalents together with univalents and bivalents were also observed. The relationship between Ljutika and Pran and their possible origin are discussed.  相似文献   

20.
A model of associative memory for time varying spatial patterns is proposed and simulated on a digital computer. This is a network composed of many neuron-like elements, and shows an ability for associative memory similar to that of the brain.Suppose a number of sequences of spatial patterns are presented to this network, for example, 12345, ABC, and so on. Then, these patterns are memorized in the network. After that, if any part of one of these sequences, say 23, is presented to the circuit, the rest of the sequence, 45, is recalled following to it. It resembles to such a situation — if we hear a part of a melody which we have memorized in the past, the rest of the melody is recalled even after it is stopped half-way. Although the recalled patterns are not always 100% correct, they are not completely destroyed even if the presented patterns are imperfect.  相似文献   

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