Free Amino Acid, Protein and Water Content Changes Associated with Seed Development in Araucaria angustifolia

The free amino acid, protein, water and dry matter contents were determined during the seed development of Araucaria angustifolia. Soluble and insoluble proteins in the mature seed represent 4.2 % of the fresh matter. The embryonic axis stored the greatest amount of soluble proteins, while cotyledons both with the embryonic axis showed the largest quantities of insoluble proteins in the mature seed. The greatest concentration of free amino acids was detected during the stage when cotyledons start to develop. Glutamic acid, aspartic acid, alanine and serine were predominant in the whole seed while arginine, lysine and γ-aminobutyric acid were present in great amounts only in cotyledons and embryonic axis. Although megagametophyte was important as a source of free amino acids, it was not the major protein storage organ in the mature seed. In the embryogenetic process, the rise of cotyledons is closely related to physiological and biochemical changes. This revised version was published online in July 2006 with corrections to the Cover Date.     

番木瓜感染环斑花叶病毒后蛋白质和还原糖的变化

本文对番木瓜不同抗性的品种感染环斑花叶病毒后,可溶性蛋白含量和电泳谱带以及还原糖含量的变化规律进行了研究,并分析其与抗性的关系。结果表明,接种处理后,感病品种(岭南种)的可溶性蛋白含量变化率的峰值较抗病品种(穗中红48号)出现早且高;前者出现在接种后24h,高达54.6%,而后者出现在接种后48h,为38.2%。在未接种处理时,感病品种叶片可溶性蛋白谱带较抗病品种多1条;但在接种初期(接种后24h),抗病品种的蛋白谱带比感病品种多1条(Rf值为0.602)。不同抗性品种在接种后的还原糖含量变化也有差异,抗病品种的还原糖含量变化率在接种后48h达到高峰,峰值为12.3%;而感病品种的还原糖含量变化率在接种后都为负值。     

Deoxyribonucleic Acid, Ribonucleic Acid, Protein and Uncombined Amino Acid Content of Legume Seeds During Embryogeny

The nucleic acid, protein and uncombined amino acid contentof seeds of soya-bean (Glycine max L. Merr.), garden pea (Pisumsativum L.), kidney bean (Phaseolus vulgaris L.) and peanut(Arachis hypogaea L.) were measured at various times duringseed formation in an effort to understand why the soya-beanhas nearly twice as much protein as the other legume seeds.In all these species the concentration of deoxyribonucleic acid,ribonucleic acid and uncombined amino acids decreased duringseed formation. The protein level of kidney bean was relativelyconstant during development whereas the protein levels of pea,peanut and soya-bean increased during development. The proteincontent of the soya-bean increased throughout development whereasthe protein increase in peanut took place early and that inpea took place later in development. The ratio of protein toribonucleic acid was highest in peanut, less in soya-bean, andlowest in pea and kidney bean. Similarly, the ratio of proteinto deoxyribonucleic acid was higher in kidney bean than in soya-bean.Soya-beans had a lower amino acid content than any of the otherseeds at all stages of development. These results indicate thatneither total deoxyribonucleic acid, ribonucleic acid nor uncombinedamino acid content is responsible for the higher protein contentof soya-beans.     

低温贮藏期间百合鳞茎中的游离氨基酸组分和含量变化

百合鳞茎的游离氨基酸主要集中在顶芽和内部鳞片等幼嫩组织中,含量最高、变化最大的是精氨酸.谷氨酸族的氨基酸在鳞茎代谢中起重要作用.顶芽的氨基酸总量及精氨酸含量随贮藏温度的升高而增加.贮藏过程中,鳞茎盘的氨基酸含量下降,顶芽和贮备组织中其含量有明显升高的过程.贮藏前期34 d内游离氨基酸含量发生显著变化.     

Studies on the Free Amino Acid Content in Anthers of Malesterile and Fertile Plants of Taigu Wheat,with Special Reference to Free Proline Content

Biochemical analyses were made on anthers and pistils at various developmental stages of both male-sterne and fertile plants of Taigu wheat. Analyses ineluded total free amino aeids and free proline. The following results were obtained: 1. There was no significant difference between the content of free proline in anthers of male-sterile and fertile plants at reduction division of mierospore mother cells. 2. In anthers with early uninucleate miorospores, the content of free proline of fertile plants was remarkably higher than that of male-sterile plants. It is interesting to note that at this stage the content of free proline in fertile plants rose to 1.65% of the dry weight of the anther, constituting 50% of the total free amino acids, and amounted to 7-fold of that in male-sterile plants. This result is in line with the results obtained with most cytoplasmic malesterile plants reported by other workers, although malesterility in Taigu wheat is controlled by the nueleus. 3. In pistils, at the stages eorresponding to the early uninneleate and the binueleate stages of the pollen, the free proline content of fertile plants was twice as much as that of the male-sterile plants. This differenee disappeared gradually after fertilization. 4. Tile content of total free amino aoids did not fluetuate as much as the free proline content. There was no differenee in anthers of both types of plants during reduction division of mierospore mother cells. In anthers with early uninueleate pollen grains, total free amino acid content of fertile plants exceeded that of male-sterile plant, the difference levelled off at latter stages. In pistils, before fertilization, the content of total free amino acids of the fertile phmts was slightly higher than that of the male-sterile plants. After fertilization t}fis difference was no nmre noticeable.     

蔬菜腌制过程中的氨基酸组成变化

在腌制过程中,芥菜的精氨酸和组氨酸等碱性氨基酸含量和氨基酸总量逐渐减少,酸性氨基酸和疏水性氨基酸含量增加。在各种氨基酸中,苏氨酸含量最高,占４４．７４％,其次是谷氨酸和丙氨酸。在腌制后,芥菜的氨基酸组成发生了显著的变化,苏氨酸下降幅度最大,而蛋氨酸、苯丙氨酸、亮氨酸、异亮氨酸、缬氨酸和赖氨酸等必需氨基酸摩尔组分显著提高。理想氨基酸模式谱的相关系数腌制前为０．０６０１７,腌制２１６小时后增到０．４９９７８,表明腌制加工可显著提高蔬菜蛋白质的营养效价。     

河川沙塘鳢胚胎、仔鱼发育过程中蛋白质含量及氨基酸库的变化

采用生物化学方法测定和分析了河川沙塘鳢(Odontobutis potamophila)胚胎、仔鱼发育过程中蛋白质含量及氨基酸的组成和含量。结果显示,从受精卵开始到孵出后8 d饥饿仔鱼的整个胚胎和仔鱼发育过程中,其总蛋白和总氨基酸含量均呈下降趋势;总的必需氨基酸含量和总的非必需氨基酸含量也一样都呈现出下降趋势;平均含量最高的氨基酸是亮氨酸Leu、赖氨酸Lys、谷氨酸Glu和天冬氨酸Asp。与总氨基酸库相反,游离氨基酸库却呈现出随着发育的进行而不断增长的趋势,这种增长趋势也反映在游离的必需氨基酸和游离的非必需氨基酸含量的变化上,并且平均含量最高的游离氨基酸是赖氨酸Lys、亮氨酸Leu、脯氨酸Pro和谷氨酸Glu。整个发育过程中,游离氨基酸的含量仅占总氨基酸库的很小一部分(在受精卵,仅占0.16%)。由于总蛋白和总氨基酸含量在发育过程中均呈下降趋势,而游离氨基酸含量呈增长趋势,由此可知,在整个胚胎发生过程中,其卵黄蛋白的水解速度大于胚体同化和异化作用对氨基酸的消耗速度。     

Developmental Changes in the Free Amino Acid Pool and Total Protein Amino Acids of Pea Cotyledons (Pisum sativum L.)

Changes in the levels of twenty-two free amino acids and in the amino acid composition of the total protein were measured throughout the development of cotyledons of a dwarf garden pea, Pisum sativum cv Greenfeast, grown in a constant environment. A sensitive double-isotope dansylation technique was used. Fresh weight, dry weight, and protein content were also followed. Twenty of the amino acids showed synchronous changes in levels, giving a developmental pattern containing four peaks; major peaks occurred very early and very late in development. The amino acid composition of the total protein, which was always very different from that of the free amino acid pool, showed early changes to one consistent with the final storage protein composition of the seed. These changes included a 50% drop in methionine content and a 70% rise in cysteine. While the maximum free methionine level occurred early in development, that of cysteine was late.     

低温对螺旋藻可溶性蛋白和游离氨基酸外渗的影响

以鄂尔多斯高原碱湖特有的钝顶螺旋藻S1、引进的钝顶螺旋藻S2和极大螺旋藻S3为材料,采用Folin法和茚三酮法分别测定低温下细胞外渗液中可溶性蛋白和游离氮基酸含量。结果表明：处理温度越低,时间越长,螺旋藻细胞外渗液中可溶性蛋白和游离氨基酸的含量越高。S1膜损伤程度最轻,比引进种S2、S3有较强的抗寒能力。判断低温对螺旋藻膜损伤的程度,用可溶性蛋白较游离氨基酸更接近于实际。     

外源一氧化氮、水杨酸和过氧化氢对烟草叶片游离氨基酸和可溶性蛋白含量的影响

测定了NO、SA和H2O2三种信号分子对烟草氮代谢产物游离氨基酸、脯氨酸和可溶性蛋白质含量的影响。结果表明：NO、SA和H2O2能调节烟草脯氨酸、游离氨基酸和可溶性蛋白质含量。低浓度的NO和H2O2处理后12h能提高脯氨酸含量,而较高浓度的NO、SA和H2O2处理降低烟草脯氨酸和游离氨基酸含量;三者对脯氨酸、游离氨基酸和可溶性蛋白质含量的影响具有相似性。     

Alterations of Free Amide and Amino Acid Contents During the Development of Maize Plants, Zea mays L.

Concentrations of free amino acids and amides were measuredin organs of maize plants, Zea mays L. in the period from 14d before pollen liberation until complete seed maturation. Inthis time anthesis took place and only the ovaries of ear 9(numbered from below) developed into seeds. In mature leaf bladesNH₄ ion assimilation had ceased and asparagine and glutaminewere not found there. N redistribution induced the occurrenceof large amounts of aspartate, glutamate and alanine. The amountsof amides in leaf sheaths and stem parts depended on the neighbourhoodof generative parts. The generative plant parts can be distinguishedfrom adjacent vegetative plant parts in concentrations of freeproline or asparagine. Proline occurred in pollen but not inthe empty anthers. Ears had a small, early peak amount of prolinemostly before pollination. Only the ninth ear had a first maximumproline amount after the fifth day of pollen liberation. A secondproline peak in the ears coincided with the period of maximumincrease in d. wt. The occurrence of proline in the generativeorgans relative to metabolic processes inducing fertility orseed maturation is discussed. Zea mays L., amides, amino acids, amino-transferring components, asparagine, glutamine, proline     

Leaf Fatty-Acid Content in Relation to Hardening and Chilling Injury

At 25?C the leaves of chill-resistant plants did not containmore unsaturated fatty acid than chill-sensitive plants. Furthermorewhen chill-sensitive plants were hardened at 12?C there wasno increase in the amount of unsaturated fatty acid or totalweight of fatty acid in the leaf. These results cast furtherdoubt on the importance of the degree of unsaturation of thefatty acids in determining the critical temperature at whichthe phase change occurs in the lipid portion of the membrane. When chill-sensitive plants are chilled (5?C) the percentageof linolenic acid and total weight of fatty acid decreases rapidlybut remains constant in chill-resistant species. Hardening mayreduce the degree of damage to the plant by slowing down detrimentalprocesses such as the decrease in the percentage of linolenicacid which occurs on chilling.     

Influence of Purines and Pyrimidines on Cold Hardiness of Plants. III. Associated Changes in Soluble Protein and Nucleic Acid Content and Tissue pH

When applications of certain purines and pyrimidines enhanced the development or maintenance of cold hardiness, the content of water-soluble, trichloroacetic acid-precipitable protein and nucleic acids and tissue pH were higher in treated plants than in controls. The reverse was generally true when the treated plants were less cold hardy than the controls. In some instances, the purines and pyrimidines increased the content of these nitrogenous constituents in a nonhardy variety to a level equal to that found in untreated plants of a hardy variety.     

Changes in Amino Acid Transport During Red Cell Maturation

We studied amino acid transport in sheep red blood cells (RBCs) as a function of cell maturation. Transport of amino acids is decreased strikingly in the mature mammalian RBC compared to the immature reticulocyte. Blood obtained 5-6 days after massive bleeding was fractionated on dextran gradients. In the mature erythrocyte amino acids are taken up only slowly, and in the normal experimental interval (60 min) the concentration in the cell does not reach that of the medium. In contrast, the reticulocyte-rich (top) fraction (50-90% reticulocytes) accumulates certain amino acids, particularly histidine, methionine, and leucine. The underlying process is ATP-independent and Na⁺-insensitive, and has properties consistent with exchange diffusion, i.e., accelerated uptake or efflux when unlabeled solute is present on the trans side. The process is apparent not only in intact cells but also in resealed ghosts. The decrease in activity of amino acid transport is a function of red cell maturation. Thus it can be shown that (a) separation of cells according to their density 1, 2, and 3 weeks after bleeding leads to progressively lower amino acid transport activity with increasing cell density; and (b) during in vitro long-term incubation at 37°C of reticulocyte-rich, unfractionated blood (5–10% reticulocytes), amino acid transport decreases while red cell integrity is maintained, as evidenced by the retention of a normal K⁺ gradient and the absence of hemolysis. The progressive loss is seen with resealed ghosts as well as with intact cells. Not all the amino acids examined participate in this exchange process. The most actively exchanged are histidine, leucine, methionine, and phenylalanine. Glycine, proline, arginine, and a-amino isobutyric acid do not participate in the exchange process.     

毛白杨幼苗低温锻炼过程中Ca2+ 的作用及细胞Ca2+-ATP酶活性的变化

观察了低温锻炼以及随后的常温生长中毛白杨幼苗质膜及线粒体Ca2 ATP酶活性、CaM含量和抗冻性的变化。结果表明 ,单纯低温锻炼在一定程度上提高了毛白杨幼苗质膜及线粒体Ca2 ATP酶活性、CaM含量和抗冻性 ,减小了低温胁迫所引起的质膜及线粒体Ca2 ATP酶活性和CaM含量的下降程度 ,促进了胁迫后恢复过程中质膜及线粒体Ca2 ATP酶活性和CaM水平的迅速回升。在低温锻炼的同时 ,用CaCl2 处理能加强低温锻炼的效果 ,但这种效应可被EGTA、LaCl3和CPZ处理所抑制     

烧伤狗浆血游离氨基酸的动态变化

烧伤狗浆血游离氨基酸的动态变化黎君友,周幼勤,赖业馥,赵有,伊少杰ＳｅｑｕｅｎｔｉａｌＣｈａｎｇｅｓｉｎＰｌａｓｍａＦｒｅｅＡｍｉｎｏＡｃｉｄＣｏｎｃｅｎｔｒａｔｉｏｎｉｎＢｕｒｎｅｄＤｏｇｓ￥Ｌｉｊｕｎｙｏｎ;Ｚｈｏｕｙｏｕｑｉｎ;Ｌａｉｙｅｆｕ;...     

Seasonal Changes in Total Free Sugar Content of Field Cocoa Plants

As part of a study of factors affecting the vegetative and reproductive characteristics of cocoa, Theobroma cacao L., (viz. leaf flushing, flowering, cherelle wilt, pod setting and pod growth), seasonal changes in total free sugar levels of the bark and wood of field cocoa trees growing under medium shade provided by Gliricidia sepium Steud. trees were studied over a period of 13 months. On dry weight basis, sugar content of the bark (13 to 63 mg/g) was higher than that of the wood (9 to 40 mg/g). Free sugar content was significantly correlated with sunshine hours for the whole period, except October-November 1975, and March 1976 when pod load, and flowering and leaf flushing respectively, caused considerable reduction in free sugar levels. The peaks of flowering and flushing coincided with those of sunshine hours and free sugar levels. The results, analysed in terms of the prevailing microclimatic conditions, suggest that light is a limiting factor for photsynthesis of shaded cocoa and that the reported stimulation of flowering and leaf flushing, which accompany shade removal, may be attributed to increased sugar status of the trees due to increased photosynthetic activity.     

Protein Content and Amino Acid Composition of Certain Fungi Evaluated for Microbial Protein Production

The protein and total amino acid contents of four mycelial fungal strains and one yeast were approximately the same for cultures harvested in the mid-log and early stationary growth phases. It was found that Fusarium oxysporum and Fusarium moniliforme contained approximately 30% more protein and total amino acids than Aspergillus niger. The amino acid composition of mycelial protein compares favorably with that of British Petroleum yeast protein Toprina produced commercially on hydrocarbon substrates. Fusarium spp. may be suitable for commercial production of microbial protein, especially when low-cost agricultural or industrial waste products are readily available as energy sources. Genetic manipulation of these fungi, such as induction of mutant strains through irradiation, may be desirable to obtain a mycelial product of improved yield and/or quality.