The relation of d-alanine and alanine racemase activity in molluscs

• 1.1. Eighteen molluscan species were examined for the presence of d-alanine and alanine racemase activity to probe the probable relation between them.
• 2.2. Two bivalve species had high concentration of d-alanine and l-alanine (1:1) and showed high activities of alanine racemase. In these species, the occurrence of d-alanine could be explained by the action of alanine racemase.
• 3.3. In other species, the levels of d-alanine and enzyme activity were low, and the occurrence of d-alanine did not correspond with the presence of alanine racemase activity.
• 4.4. The mechanism of the occurrence of d-alanine in molluscan tissues seems to vary from species to species and seems not to be associated with the phylogenic situation or habitats of the respective species.

     

One and two dimensional isoelectric focusing of lactate dehydrogenase from the tissues of Ovis aries

• 1.1. Lactate dehydrogenase in ovine tissues was separated by electrophoresis, one dimensional isoelectric focusing (IEF) and a two dimensional technique.
• 2.2. Tissues showed five zones of enzyme activity consisting of multiple bands after IEF.
• 3.3. The IEF zymograms were unique for each tissue and differed from those of other species.
• 4.4. Two dimensional separation revealed that the five zones of activity observed on IEF corresponded to the five isoenzymes separable by conventional electrophoresis.

     

Temperature acclimation in respiratory and cytochrome c oxidase activity in common carp (Cyprinus carpio)

• 1.1. Common carp (Cyprinus carpio) exposed to experimental temperatures of 12, 18, 24, 30 or 36°C for a 4-week period were used to investigate the effect of temperature acclimation on the frequency of opercular movement (FOM), growth and cytochrome c oxidase (CCO) activity in heart, liver and muscle.
• 2.2. An exponential relationship between FOM and temperature after the first week (10₁₀ =1.76) disappeared after the second week.
• 3.3. The initially high FOM at temperatures of 30 or 36°C and the low FOM at 18 or 12°C changed over 4 weeks to approach the FOM of fish at 24°C.
• 4.4. This change in the relationship of FOM to temperature from highly dependent to independent appeared to be thermal compensation.
• 5.5. Heart and liver CCO activities were significantly affected by temperature, with the lowest activity at the approximate optimum temperature for growth, 24°C.
• 6.6. Highest CCO activities for heart and liver occurred at both the highest and lowest temperatures.
• 7.7. Among the three tissues, heart CCO activity was generally the highest and most affected by acclimation temperature.
• 8.8. Muscle tissue had the lowest CCO activity and was unaffected by temperature.
• 9.9. The high CCO activity at a cold acclimation of temperature 12°C was probably due to thermal compensation and the high activity at 36°C may have been a result of thermal stress.

     

Biochemical and calorific content of deep-sea aspidochirotid holothurians from the northeast atlantic ocean

• 1.1. The organic composition of the body tissues of eight species of deep-sea aspidochirotid holothurian, collected between 500 and 4100m depth in the NE Atlantic Ocean, was obtained by the biochemical analysis of protein, lipid, carbohydrate and % ash.
• 2.2. The major organic class was protein with soluble lipid the major soluble fraction in the ovary. Carbohydrate values were consistently low.
• 3.3. The calorific value was significantly higher in the ovary than in the other tissues.
• 4.4. The total body calorific content for two selected species, Benthothuria funebris and Mesothuria lactea, was 25.62 and 26.24J/mg ash-free dry weight (AFDW).

     

Activities of the three ammonia-forming enzymes in the tissues of the brackish-water bivalve Corbicula japonica

• 1.1. Activities of the three ammonia-forming enzymes, glutamate dehydrogenase, AMP deaminase and serine dehydrase (SerDH), were measured in tissues of gill, digestive diverticula, mantle and foot muscle of the brackish-water bivalve Corbicula japonica.
• 2.2. High levels of SerDH activity were detected in gill and digestive diverticula, while the activity levels of the other two enzymes were low.
• 3.3. The result suggests the significance of SerDH in amino acid degradation of this species.

     

Simultaneous Quantification of Protein Expression and Modifications by Top-down Targeted Proteomics: A Case of the Sarcomeric Subproteome

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Highlights

• •A new strategy for simultaneous quantification of protein expression and modification.
• •This top-down LC/MS-based method shows high reproducibility and high throughput.
• •Quantification at the intact protein level with results comparable to Western blot.
• •This top-down proteomics method is applicable to different species and tissues.

     

Relationship between brain trehalase activity and trehalosema during direct and diapausing development in Pieris brassicae

• 1.1. Brain trehalase specific activity and trehalosemia were measured during the end of the developmental life cycle in non-diapausing and diapausing insects.
• 2.2. During non-diapausing development, trehalosemia reached maximum values at the beginning of pupal life. Then a constant decrease was observed up to the end of adult life.
• 3.3. The specific activity of brain trehalase was maximum when the insects were in active feeding periods, minimum activity appearing during moulting phases.
• 4.4. During diapausing development, trehalosemia was very high at the beginning of pupal life, particularly when insects were exposed to wintering conditions.
• 5.5. When diapause was broken, trehalosemia fell, announcing adult emergence.
• 6.6. Brain trehalase activity showed the same qualitative variations as in non-diapausing larvae, but with rather lower values.
• 7.7. During pupal life, brain trehalase activity decreased markedly during the long period necessary to obtain diapause breakdown.
• 8.8. Wintering conditions allow a progressive increase of brain trehalase activity, which preceded the fall of trehalosemia.

     

Phenoloxidase activity of acridid grasshoppers from the subfamilies melanoplinae and oedipodinae

• 1.1. Phenoloxidase activity and wound melanization was studied in five species of grasshoppers representing the subfamilies Melanoplinae and Oedipodinae.
• 2.2. Most of the phenoloxidase activity was detected in the plasma fraction of grasshopper whole-body homogenates and supernatant fractions of the hemolymph. The species representing the Oedipodinae had 20–50% higher percentage of the total phenoloxidase activity associated with particulate matter from a whole-body homogenate when compared to the Melanoplinae.
• 3.3. Phenoloxidase activity could not be detected in sclerotized cuticle of adult grasshoppers.
• 4.4. The phenoloxidase existed as a zymogen which could be activated by chymotrypsin and inhibited by KCN and NaCN while EDTA showed no effect. It had optimum activity at 37°C and pH 7.3.
• 5.5. These findings are discussed in relation to wound repair and immune responses to infection in grasshopper species.

     

Polymorphism and tissue specificity of scallop tropomyosin

• 1.1. Molecular polymorphism of tropomyosin from various muscle sources of the scallop, Patinopecten yessoensis, was investigated by electrophoretic and immunochemical methods.
• 2.2. Treatment of the muscle sources with trichloroacetic acid (TCA) prior to tropomyosin preparation was found useful to prevent proteolytic degradation of this protein.
• 3.3. Electrophoretic and immunochemical analysis revealed that at least six kinds of tropomyosin isoforms may exist in scallop muscle tissues.
• 4.4. The tropomyosin isoforms showed tissue-specific distribution in amounts and molecular species among the various muscle sources.

     

Distribution of serine esterase activity in the lymphoid system of C57bl/6 mice,effect of aging on the enzymatic activity

• 1.1. The activity of serine esterase (SE) was investigated in the lymphoid system of C57BL/6 mice. SE activity increased in the lymphoid tissues with their content of mature T-lymphocytes, except that high levels were also observed in various populations of bone marrow cells.
• 2.2. The maturation of T-lymphocytes in the thymus was accompanied by an increase in their SE activity.
• 3.3. Experiments on the influence of age on SE activity showed that while thymocytes were not affected, a three-fold increase in activity occurs in spleen lymphocytes between the ages of 26 and 78 wk.

     

Human GMP synthetase

• 1.1. The specific activity of GMP synthetase was measured in several human tissues and found to be highest in cultured skin fibroblasts, followed by bone marrow, leukocytes, erythrocytes. placenta, and liver.
• 2.2. The enzyme from fibroblasts was purified approximately 50-fold by ammonium sulfate fractionation and gel filtration.
• 3.3. The K_m values were determined to be 4.9μM for XMP, 270μM for ATP. and 340 μM for glutamine.
• 4.4. Ammonium sulfate could replace glutamine as the amino donor but was much less efficient.
• 5.5. The enzyme was specific for ATP as the energy source.
• 6.6. Unlike the calf thymus enzyme, the human enzyme has no requirement for a reduced sulfhydryl compound.
• 7.7. Human GMP synthetase is inhibited by ATP, dATP, azaserine, and hydroxylamine.

     

Anuran amphibia which are not acclimable to high salt,tolerate high plasma urea

• 1.1. The capacity of five anuran Amphibians (Bufo viridis B. regularis, Rana ridibunda, Hyla arborea and Pelobates syriacus) to acclimate to NaCl and urea solutions was investigated.
• 2.2. All species could be acclimated to relatively high concentrations of urea solutions, while only Bufo viridis and Hyla arborea could be acclimated to 500 mOsm/kg or higher NaCl solutions.
• 3.3. The plasma urea concentration in B. viridis and H. arborea was elevated to levels over 140 mmol/1.
• 4.4. The sum of plasma sodium and chloride concentrations did not increase over 400 mmol/l in any species.
• 5.5. Urine osmolality, which was normally low, increased, but never exceeded the plasma osmolality.
• 6.6. In the urea acclimation conditions, urine electrolytes diminished, similarly in all species in this study.
• 7.7. It is concluded that anuran Amphibians can tolerate high plasma urea concentrations, but only those species which can elevate it, either through retention or net synthesis, can be acclimated to high salt solutions.

     

Purification and characterization of lipoprotein lipase from the white adipose,skeletal muscle,cardiac muscle,mammary gland and lung tissues of the rat

• 1.1. Lipoprotein lipase (LPL) was isolated from five rat tissues: white adipose, skeletal muscle, cardiac muscle, mammary gland and lung.
• 2.2. Specific activity of the preparations varied from 75 U/mg for skeletal muscle and 720 U/mg for adipose.
• 3.3. The preparations were further analysed using SDS-PAGE and a single component identified. The mol. wt of 61,000 Da of this component was consistent for all five of the tissue sources.
• 4.4. Significant differences in the values of the isoelectric points of the enzyme species were revealed. The values varied from 7.23 (SEM 0.022) for cardiac and lung to 7.51 (SEM 0.037) for mammary.
• 5.5. Two-dimensional electrophoresis, using isoelectric focusing in the first dimension and SDS-PAGE in the second revealed differences in the patterns of stained material derived from the five tissue sources.

     

Human seminal phosphatase: Properties and comparison with plant phosphatases

• 1.1. Phosphatase activities were determined in various seminal fluid and plant tissues.
• 2.2. Human semen showed a markedly higher phosphatase activity, and some plants and mushrooms exhibited a considerably higher phosphatase activity.
• 3.3. Phosphatase purified from human seminal fluid showed a pH optimum of 5–6 and was potently inhibited by l-(+)-tartrate.
• 4.4. Tartrate could not inhibit most plant phosphatases, but inhibited the mushroom phosphatase with a one-order lower affinity than that of the seminal enzyme.

     

A comparison of aspartate transcarbamylase activity in juvenile pacific oysters (Crassostrea gigas) when fed various diets

• 1.1. The optimum pH for measurement of aspartate transcarbamylase activity in oyster tissue was determined to be 9.35 while the optimum temperature was 39.5°C.
• 2.2. Aspartate transcarbamylase activity varied significantly over short periods of time (hr) possibly due to fluctuations in the amount of food digested.
• 3.3. The composition of the oyster's diet also affected the levels of aspartate transcarbamylase activity in oyster tissues.
• 4.4. Those oysters fed an egg yolk-starch diet contained significantly lower aspartate transcarbamylase activity than oysters fed an egg yolk-starch-salmon oil diet or a casein-starch-salmon oil diet.
• 5.5. The aspartate transcarbamylase activities in oysters fed Phacedactylum tricornutum or a starch diet were not significantly different from the activities in oysters fed the egg yolk-starch diet.

     

Renin-angiotensin system in antarctic fishes

• 1.1. The presence of a renin-angiotensin-like system has been investigated in the Antarctic fishes Chionodraco hamatus (Fam. Channichthydae) and Pagothenia (Trematomus) bernacchii (Fam. Notothenidae).
• 2.2. A renin-like activity is present in plasma and kidney of both the white blooded (Chionodraco) and the red blooded (Pagothenia) species.
• 3.3. An angiotensin converting enzyme-like activity has been demonstrated in plasma, gills and kidneys of both species. The activity is inhibited by high temperature.
• 4.4. From our data a renin-angiotensin-like system is present in the Antarctic fishes studied but the cascade of enzymes is active only at low temperatures.

     

Distribution of tetracycline in haemolymph and tissue of all stages of corn earworm (Heliothis zea boddie)

• 1.1. Insects reared on tetracycline containing diets had lower mortality, but required more time to reach the pupal stage.
• 2.2. Tetracycline diffuses and dissipates readily into and out of insect blood and tissues.
• 3.3. It reduces biosynthesis of high molecular weight proteins in blood.
• 4.4. Apportionment of tetracycline in the pupal tissue is uneven.

     

Glycolytic enzymes of fowl and turkey spermatozoa

• 1.1. It was confirmed that, under anaerobic conditions, fowl spermatozoa formed lactate from glucose thirteen times faster than turkey spermatozoa.
• 2.2. The profiles of glycolytic enzyme activities were similar for spermatozoa from both species; however fowl spermatozoal activities were generally 2- to 4-fold higher.
• 3.3. Exceptions were glycerophosphate mutase and lactate dehydrogenase activities which were respectively 9.5 and 41 times greater in fowl spermatozoa.
• 4.4. In both species, spermatozoal glyceraldehyde-3-phosphate dehydrogenase had the lowest activity of the glycolytic enzymes.

     

Distribution of free l-histidine and related dipeptides in the muscle of fresh-water fishes

• 1.1. From the muscle of 20 species of fresh-water fishes, l-histidine, carnosine, anserine, and balenine were analysed by high-performance liquid chromatography.
• 2.2. All cyprinoidei fishes contained significant amount of l-histidine and trace of dipeptides.
• 3.3. High concentration of anserine was found in salmonoidei fishes, irrespective of salmonidae and osmeridae.
• 4.4. Two species of anguilloidei contained large amount of carnosine, small of l-histidine, and determinable of anserine and balenine.
• 5.5. Only trace amounts of these compounds were found in percoidei fishes.
• 6.6. The levels of these compounds represented no large difference among species belonging to sub-order group as well as family.