Cytological composition of lymph in fever reaction

This work deals with an investigation into the lymph cytologic composition of thoracic lymph duct of rabbits in fever reaction (FR) of various duration. FR was accompanied by quantitative and qualitative shifts in lymph cytologic composition. There was an alternative rise and fall of the leucocyte number in the first hours of fever. The number of little and medium leucocytes decreased while the number of eosinophiles, insufficiently differentiated cells-blasts, large lymphocytes, prolymphocytes increased. Our investigations revealed a significant role played by the lymphatic system in lymphoid cells mobilization in FR, which is evident by a considerable lymphocyte number gaining entrance to the blood through thoracic duct.     

Individual amino acid balances in young lean and obese Zucker rats fed a cafeteria diet

The amino acid composition of the diet ingested by reference and cafeteria diet-fed lean and obese Zucker rats has been analyzed from day 30 to 60 after birth. Their body protein amino acid composition was measured, as well as the urinary and faecal losses incurred during the period studied. The protein actually selected by the rats fed the cafeteria diet had essentially the same amino acid composition as the reference diet. The mean protein amino acid composition of the rat showed only small changes with breed, age or diet.Cafeteria-fed rats had a higher dietary protein digestion/absorption efficiency than reference diet-fed rats. Obese rats wasted a high proportion of dietary amino acids when given the reference diet, but not on the cafeteria diet. In all cases, the amino acids lost as such in the urine were a minimal portion of available amino acids.In addition to breed, the rates of protein accretion are deeply influenced by diet, but even more by the age — or size — of the animals: cafeteria-fed rats grew faster, to higher body protein settings, but later protein accrual decreased considerably; this is probably due to a limitation in the blueprint for growth which restricts net protein deposition when a certain body size is attained. Obese rats, however, kept accuring protein with high rates throughout.Diet composition — and not protein availability or quality-induced deep changes in amino acid metabolism. Since the differences in the absolute levels of dietary protein or carbohydrate energy ingested by rats fed the reference or cafeteria diets were small, it can be assumed that high (lipid) energy elicits the changes observed in amino acid metabolism by the cafeteria diet. The effects induced in the fate of the nitrogen ingested were more related to the fractional protein energy proportion than to its absolute values. Cafeteria-fed rats tended to absorb more amino acids and preserve them more efficiently; these effects were shown even under conditions of genetic obesity.There were deep differences in handling of dietary amino acids by dietary or genetically obese rats. The former manage to extract and accrue larger proportions of their dietary amino acids than the latter. The effects of both models of amino acid management were largely additive, suggesting that the mechanisms underlying the development of obesity did not run in parallel to those affecting the control of amino acid utilization. Obesity may be developed in both cases despite a completely different strategy of amino acid assimilation, accrual and utilization. (Mol Cell Biochem121: 45–58, 1993)     

The amino acid composition of blood serum of harp seal pups in the period of adaptation to captivity]

It is cited results of investigation of amino acid composition of blood serum of harp seal pups in the first days after catch adaptation in conditions of oceanarium. It is shown that changes of amino acid composition are most expressed in the first ten-day period of observation and manifest itself by increase of free amino acid concentration at the expense of their endogenous entrance in blood. At the same time it was detected amino acid imbalance which is conditioned by stress of animals. Results of investigation witness intensification of protein catabolism under conditions of stress. Because of it it is necessary to correlate protein metabolism for prophylaxis of hypotrophy seal pups.     

Isolation and physico-chemical properties of rat ceruloplasmin

Ceruloplasmin was isolated and purified from albino rat blood serum. Relative molecular mass of the protein is 130 000. Electrophoresis of the protein preparations leads to a formation of the apo-protein devoid of the oxidase activity and migrating slower than the holo-protein. Leucine was found to be the N-terminal amino acid of the ceruloplasmin polypeptide chain. The amino acid composition and carbohydrate content of the protein were determined. The tryptic peptide maps of rat ceruloplasmin were compared to those of human protein. The properties of rat and human ceruloplasmin are discussed with respect to copper metabolism in animal body as well as in normal humans and patients with Wilson's disease.     

Amino acid composition and the evolutionary rates of protein-coding genes

Summary Based on the rates of amino acid substitution for 60 mammalian genes of 50 codons or more, it is shown that the rate of amino acid substitution of a protein is correlated with its amino acid composition. In particular, the content of glycine residues is negatively correlated with the rate of amino acid substitution, and this content alone explains about 38% of the total variation in amino acid substitution rates among different protein families. The propensity of a polypeptide to evolve fast or slowly may be predicted from an index or indices of protein mutability directly derivable from the amino acid composition. The propensity of an amino acid to remain conserved during evolutionary times depends not so much on its being features prominently in active sites, but on its stability index, defined as the mean chemical distance [R. Grantham (1974) Science 185862–864] between the amino acid and its mutational derivatives produced by single-nucleotide substitutions. Functional constraints related to active and binding sites of proteins play only a minor role in determining the overall rate of amino acid substitution. The importance of amino acid composition in determining rates of substitution is illustrated with examples involving cytochrome c, cytochrome b₅,ras-related genes, the calmodulin protein family, and fibrinopeptides.     

Effect of cold-temperature exposure and acclimation on amino acid pool changes and enzyme activities of rat brown adipose tissue

The amino acid pool composition and its concentration ratios with respect to blood and plasma, as well as the activities of alanine, aspartate and branched chain amino acid transaminases, glutamine synthetase, adenylate deaminase and glutamate dehydrogenase have been studied in the interscapular brown adipose tissue of control, 12-h cold-exposed and 15-day cold-acclimated rats. Cold temperature affected the amino acid metabolism and pool composition more intensely after 15 days than after 12-h cold-exposure, even though the patterns of change were very similar in both groups. Cold temperatures induced a decrease in glutamine and an increase in glutamate concentration in the tissue. This probably increased the metabolism of branched chain amino acids and caused a decrease in adenylate deaminase activity. It also seemed to increase alanine utilization. We concluded that amino acid metabolism in brown adipose tissue is enhanced by cold temperature acclimation.     

Inhibition and promotion by light of the accumulation of translatable mRNA of the light-harvesting chlorophyll a/b-binding protein of photosystem II

The amount of in-vitro translatable mRNA of the light-harvesting chlorophyll a/b-binding protein (LHCP) of photosystem II strongly increases in darkness (D) after a 5-min red-light pulse while continuous illumination of mustard seedlings with far-red (FR), red or white light leads only to a slight increase in the amount of translatable LHCP-mRNA. No increase can be observed after a long-wavelength FR (RG9-light) pulse. However, a FR pretreatment prior to the RG9-light pulse strongly increase LHCP-mRNA accumulation in subsequent D. This is not observed in the case of the mRNA for the small subunit of ribulose-1.5-bisphosphate carboxylase. The increase of LHCP-mRNA in D after a FR pretreatment can be inhibited by a reillumination of the seedlings with FR. The inhibition of LHCP-mRNA accumulation during continuous illumination with FR and the strong increase in D following a FR illumination was found to be independent of chlorophyll biosynthesis since no correlation between chlorophyll biosynthesis and translatable LHCP-mRNA levels could be detected. Even strong changes in the amount of intermediates of chlorophyll biosynthesis caused by application of levulinic acid or 5-aminolevulinic acid did not affect LHCP-mRNA levels. Therefore, we conclude that the appearance of LHCP-mRNA is inhibited during continuous illumination, even though illumination leads to a storage of a light singal which promotes accumulation of translatable LHCP-mRNA in D.Abbreviations c continuous - Chl chlorophyll - D darkness - FR far-red light (3.5 W·m^-2) - LHCP light-harvesting chlorophyll a/b-binding protein of photosystem II - NF Norfluration - PChl protochlorophyll(ide) - Pfr far-red absorbing form of phytochrome - Ptot total phytochrome - R red light (6.8 W·m^-2) - RG9-light long-wavelength FR (10 W·m^-2) - SSU small subunit of ribulose-1.5-bisphosphate carboxylase - WL white light - () Pfr/Ptot=wavelength-dependent photoequilibrium of the phytochrome system     

Amino acid exchange mechanism in the basolateral membrane of the midgut epithelium from the larva ofHyalophora cecropia

Summary It is concluded that the amino acid, -aminoisobutyric acid, is taken up from the blood into the midgut epithelium by an exchange mechanism for the following reasons: 1. The amino acid uptake becomes saturated with increasing amino acid concentration on the blood side; 2. The amino acid in the tissue cannot be washed out again to the blood side unless an amino acid is present in the blood side bathing solution; 3. The uptake mechanism is independent of metabolism. This amino acid exchange mechanism is independent of the active transport of potassium from blood side to lumen side, the exchange of potassium between blood and midgut tissue, and the transport of the amino acid, -aminoisobutyric acid, across the midgut epithelium from lumen to blood.     

Changes in Free Amino Acid Production and Intracellular Amino Acid Pools of Bacillus licheniformis as a Function of Culture Age and Growth Media

Changes in the endogenous intracellular amino acid pool and total free amino acid production in Bacillus licheniformis grown in minimal media were investigated. The total intracellular pool increased during exponential growth and then decreased rapidly after the end of growth. Most of the amino acids were present at low concentrations, but glutamate and alanine comprised 60 to 90% of the total intracellular free amino acid at most times during the growth cycle. It was concluded that, in addition to providing monomers for protein synthesis, the intracellular amino acid pool may be maintained for the storage of energy-providing metabolic intermediates and possibly as a balance to the ionic strength of the medium. The total free amino acid production by the cell was found to be dependent upon the composition of the salts medium as well as the culture age under conditions in which the carbon and nitrogen sources were the same. A 10-fold increase in extracellular amino acid was observed as the cells changed from vegetative to sporulation metabolism, mostly due to the extrusion of intracellular amino acid. The impact of this increase upon amino acid uptake and pulse-labeling studies using unwashed cells is discussed.     

Amino acid composition of the lymph and blood in allergic transformations of the body

The time-course of changes in the content of free amino acids and total protein in lymph of the thoracic duct and peripheral blood was studied in dogs during sensitization and anaphylactic shock (AS). Allergic rearrangement of the body during AS was accompanied by considerable disorders in redistribution of free amino acids in body fluids (blood, interstitial fluid and lymph). It is assumed that changes in the quantitative ratios occurring between individual amino acids during metabolic processes under sensitization are likely to cause protein biosynthesis disorders in the body experiencing allergic rearrangement.     

Some aspects of amino acid metabolism in the rat fetus

• 1.1. In spite of an eventual catabolic phase during the last third of pregnancy, nitrogen retention seems to increase in pregnant rats. Furthermore, the high uterine blood flow and the high placental transfer of amino acids maintains an adequate nutrient supply to the fetuses.
• 2.2. The terminal rat fetus has a high circulating plasma amino acid level, as well as an increased free amino acid tissue pool when compared to its mother's.
• 3.3. In the rat fetus the development of enzymatic capabilities shows a sudden emergence (also denomined clustering) in late fetal life. In a general trend, the activities of enzymes related with amino acid metabolism are not well developed during rat fetal life.
• 4.4. The rate of amino nitrogen excertion in rat fetus is low, mainly due to the low development of urea cycle enzyme activities.
• 5.5. The rates of protein synthesis in many tissues are high in the rat fetus and they show a progressive decrease until delivery. On the other hand, the rates of protein breakdown are also higher during fetal life than in the adult.

     

Molecular correlates of tissue browning and deterioration in Scots pine calli

Callus cultures were initiated from the bud apices of 10–40-year-old Scots pines (Pinus sylvestris L.) at different seasons and maintained on modified MS medium without subculturing. Separate sets of experiments were used for analyses of carbohydrate content, ethylene production, amino acid composition, protein patterns andin vitro translation. In each case the change in the colour of the calli was recorded and the fresh mass of the samples measured. The onset of tissue browning was found to be associated with changes in protein pattern, amino acid content, ethylene production and the occurrence of sucrose and accumulation of starch.In vitro translation experiments using poIy(A)⁺ RNA isolated and purified from the calli indicated that the switch in metabolism accompanying browning is paralleled by activated protein synthesis. Thus, the development of brown colour does not as such seem to be harmful to the tissue. The later, more intense tissue browning and deterioration which is reflected in a reduced capacity for protein synthesis and changes in the free amino acid pool and protein pattern is probably a secondary phenomenon.     

Effect of norleucine on the metabolism of tobacco cells in suspension cultures

The phenolic content of tobacco cells in suspension cultures rose during the initial stages of growth and then fell again. Norleucine treatment prevented this initial rise in production of phenolics, but a steady level of the compounds was maintained. No significant changes in the type of phenolics produced was observed. Norleucine had a slight effect on the amino acid composition of proteins probably by changing the relative amounts of soluble proteins. The free amino acid pool was changed drastically and the amount of free glutamine especially was reduced. A slight increase of ethylene production was noted, perhaps due to a sparing action of norleucine on methionine. The results are discussed in terms of the possible use of an amino acid antagonist such as norleucine to change cell metabolism and cell composition without changing cell growth.     

Inhibition of fatty acid synthesis prevents the incorporation of aldosterone-induced proteins into membranes.

2-Methyl-2-[p-(1,2,3,4-tetrahydro-1-naphthyl)phenoxy]propionic acid (TPIA), an acetyl coenzyme A carboxylase inhibitor, blocks the aldosterone-induced increase in transepithelial sodium transport. To examine the requirement for ongoing fatty acid synthesis and/or elongation in the aldosterone-induced alteration of cellular protein metabolism in the toad's urinary bladder, the effect of TPIA has been examined in double-labeled amino acid incorporation experiments. TPIA itself has no effect on the pattern of protein labeling in either the "soluble" or a plasma membrane-enriched fraction. However, inhibition of fatty acid synthesis selectively inhibits the aldosterone-induced incorporation of membrane proteins without altering the labeling of soluble cell protein. These results indicate that ongoing fatty acid synthesis is required for the hormone-induced changes in plasma membrane protein metabolism.     

Effect of acute intestinal obstruction on erythrocyte membrane function

The amino acid composition of red blood cell membrane proteins had been studied in different stages of acute intestinal obstruction. Hydrophobic amino acids were revealed to increase and glutamate was found to decrease during the early period of acute intestinal obstruction. Later neutral amino acids and some of the main amino acids were stated to decrease. Shifts in the ratio of protein fractions seen in red blood cell membrane of rats with acute intestinal obstruction could be explained by changes followed in the amino acid composition. The data accumulated had demonstrated that such a significant modification of protein component of the red blood cell membrane could be one of the reasons of the erythrocyte membrane penetrability violation and could play the pathogenetic role in the occurrence of irreversibility changes in cases of the intestinal obstruction. All that was mentioned above had shown the necessity to use membrane protectors and antienzyme drugs in the postoperative period.     

Biochemical aspects of growth-stimulating effects of steroid phytohormones on lupine plants

Presowing treatment of seeds of lupine of various species and cultivars with brassinosteroids—homobrassinolide and epibrassinolide—caused an increase in protein content and a change in the proportion of some amino acids. Both hormones increased heterogeneity of high-and medium-molecular-weight nonhistone chromatin proteins but had no effect on the polypeptide profile of histones. Using epibrassinolide as an example, we showed that the brassinosteroid-induced increase in protein content in lupine seeds was due primarily to accumulation of the low-molecular-weight components of β-conglutin. The content of some amino acids in both α-and β-conglutins changed. These changes in protein metabolism correlated with an increase in the content of indoleacetic acid and a decrease in the content of abscisic acid.     

Biochemical aspects of growth-stimulating effects of steroid phytohormones on lupine plants

Presowing treatment of seeds of lupine of various species and cultivars with brassinosteroids--homobrassinolide and epibrassinolide--caused an increase in protein content and a change in the proportion of some amino acids. Both hormones increased heterogeneity of high- and medium-molecular-weight nonhistone chromatin proteins but had no effect on the polypeptide profile of histones. Using epibrassinolide as an example, we showed that the brassinosteroid-induced increase in protein content in lupine seeds was due primarily to accumulation of the low-molecular-weight components of beta-conglutin. The content of some amino acids in both alpha- and beta-conglutins changed. These changes in protein metabolism correlated with an increase in the content of indoleacetic acid and a decrease in the content of abscisic acid.     

Isolation and preliminary characterization of a Cd-binding protein from Tenebrio molitor (Coleoptera)

The effect of cadmium (Cd) exposure on Cd-binding ligands was investigated for the first time in a beetle (Coleoptera), using the mealworm Tenebrio molitor (L) as a model species. Exposure to Cd resulted in an approximate doubling of the Cd-binding capacity of the protein extracts from whole animals. Analysis showed that the increase was mainly explained by the induction of a Cd-binding protein of 7134.5 Da, with non-metallothionein characteristics. Amino acid analysis and de novo sequencing revealed that the protein has an unusually high content of the acidic amino acids aspartic and glutamic acid that may explain how this protein can bind Cd even without cysteine residues. Similarities in the amino acid composition suggest it to belong to a group of little studied proteins often referred to as "Cd-binding proteins without high cysteine content". This is the first report on isolation and peptide sequence determination of such a protein from a coleopteran.     

Amino acids of barley plants in relation to nitrate,urea or ammonium nutrition

Summary When barley seedlings were transplanted into media containing either nitrate, ammonium, or urea their protein and free glutamate content increased during the first few hours. Following the commencement of active growth both the ammonium and urea assimilating plants showed greater increase in free aspartate and organic nitrogen content than the nitrate assimilating plants. Form of nitrogen had no effect on protein concentration and composition, and was of little importance as a source of differences in the total amino acid composition of the plant. re]19740503     

The role of free amino acids in osmoregulation of cricket blood (Acheta domesticus)

The blood volume increased during normal feeding, and did not decrease during fasting at the end of the stadium. The unexpectedly high blood volume of starved crickets might be an adaptation to increase chances for moulting via stretch receptor stimulation.The amount of blood amino acids was not changed by feeding, but increased with fasting or starvation. Thus amino acid levels in the blood were not directly related to amino acid input from the gut.The blood protein concentration did not change during starvation, but the amino acid concentration was 33% higher in starved crickets that drank water as opposed to those given saline to drink. Thus amino acid levels in the blood were not related directly to blood protein concentration.The blood amino acid concentration was 19–22 mM/l in response to salt intake by feeding crickets or starved crickets drinking saline. The concentration was 32–38 mM/l when the crickets were fasting prior to and after ecdysis or when starved with water to drink during the time when they would normally be feeding. The increase of amino acids during fasting was due to a proportional increase in all amino acids augmented by a 3 × increase in tyrosine. The increase during salt depleting starvation was due to a doubling of the two predominant amino acids proline and glycine. Proline and glycine were not increased in starved crickets drinking saline, thus starvation was not the reason for the increase. This is the first instance where specific amino acids have been implicated in osmoregulation.