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1.
- 1.1. Blood samples were obtained from an adult female Hubbs' beaked whale and her fetus.
- 2.2. Two major hemoglobins were demonstrated by cellulose acetate electrophoresis and were purified by ion exchange chromatography from each specimen.
- 3.3. The relative amounts of these components were different in the adult and fetus.
- 4.4. Both of these hemoglobins have a higher affinity for oxygen than normal human hemoglobin.
- 5.5. Maternal and fetal hemoglobins were separated and the N-terminal amino acid of each of these hemoglobins was found to be valine.
- 6.6. Tryptic peptide separation and amino acid analyses of the purified polypeptide chains indicated that the hemoglobins of the fetal sample were identical to those of the maternal.
2.
- 1.1. Antisera produced in rabbits by immunization with vascular hemoglobins of the earthworm Lumbricus terrestris and horseleech Haemopsis marmorata were tested for the ability to cross-react with heterologous hemoglobin.
- 2.2.Two of eight antisera demonstrated immunological cross-reactivity between the hemoglobins studied.
- 3.3.The structural basis for this cross-reactivity is briefly considered.
3.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1983,74(2):221-225
- 1.1. Changes in the hemoglobins present in many vertebrates have been observed during development and during anemic episodes.
- 2.2. A change in the number of hemoglobins present and their relative amounts was observed when adult Triturus cristalus newts were made anemic by injection of acetylphenylhydrazine.
- 3.3. Hemoglobin IV, which is a minor hemoglobin in healthy adults, was found to be a major component during the subsequent erythropoietic response to hemolytic anemia.
- 4.4. No new hemoglobin not already present in the non-anemic state was detected during the response to induced anemia.
4.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(1):239-244
- 1. The equilibria and kinetics of oxygen binding by blood and hemoglobin from adult and fetal caecilians,Typhlonectes compressicauda, have been measured.
- 2. The oxygen affinity of fetal blood is higher than that of adult blood.
- 3. Electrophoresis of adult and fetal hemoglobins suggests that they may be identical: a major and minor component occurs in each.
- 4. Adult and fetal hemoglobins have identical oxygen equilibria. Stripped hemoglobins have a high oxygen affinity and no Bohr effect between pH 6.5 and 10.0. An “acid”, reversed Bohr effect is present below pH 6.5. The addition of 1 mM ATP reduces the oxygen affinity markedly and produces a moderate, normal Bohr effect.
- 5. The major nucleoside triphosphate in fetal and adult erythrocytes is adenosine triphosphate: about 10% of the nucleoside triphosphates is guanosine triphosphate. Adult erythrocytes contain 3 times as much ATP as do the fetal erythrocytes.
- 6. The fetal to maternal shift in the oxygen equilibrium is mediated entirely by the difference in ATP content of the maternal and fetal red blood cells.
5.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1983,74(4):731-736
- 1.1. The extracellular hemoglobins of the crustacean Artemia can be split into structural and functional domains by limited proteolysis.
- 2.2. The oxygen affinity of the multi-domain fragments increases linearly with decreasing molecular weight.
- 3.3. Cooperativity is expressed only in the intact dimeric molecule and not at the subunit or multi-domain level.
6.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1980,65(4):555-559
- 1.1. Liophis miliaris and Helicops modestus are water snakes having different respiratory adaptiations to their specific habitats. L. miliaris is more active and spends more time on land than H. modestus. Knowledge of the equilibrium and kinetics of ligand binding to their hemoglobins leads to better understanding of molecular aspects of this adaptation.
- 2.2. Both snakes contain several hemoglobin types in their blood. Studies on the kinetics of oxygen dissociation and carbon monoxide combination with these hemoglobins were performed by stopped-flow and flash-photolysis experiments at various pH values, both in the presence and absence of adenosine triphosphate.
- 3.3. The oxygen dissociation kinetics of L. miliaris hemoglobins show a strong pH dependence and cooperative interactions between chains are indicated by autocatalytic time-courses at pH 7.0. In contrast, H. moledstus hemoglobins show nearly pH independent rate constants for oxygen dissociation and cooperative interactions between chains were not apparent. The hemoglobins of H. modestus show increased pH dependence in the presence of adenosine triphosphate.
- 4.4. The carbon monoxide combination kinetics differ for the hemoglobins of L. miliaris and H. modestus in general agreement with the differences found in the kinetics and equilibria of oxygen binding. Both the kinetic and steady-state difference between these hemoglobins may be advantageous in light of the behavioral differences of these two water snakes.
7.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(1):173-177
- 1. The four main hemoglobin components of the hemolysate ofPterygoplichthys pardalis have been isolated and characterized.
- 2. The functional properties investigated for the isolated components comprise the effect of pH and ATP on (i) the O2 equilibrium, (ii) the O2 dissociation kinetics, (iii) the CO combination kinetics.
- 3. Component I, corresponding to approx 50% of the total hemoglobin, is characterized by functional properties which are distinctly different from those of Components II, III and IV, which are alike
- 4. Thus it is shown, once more, that multiple components in an hemolysate fall into categories of hemoglobins characterized by distinct and complementary functional properties
8.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1989,92(4):823-827
- 1.1. The hemoglobins of Leporinus friderici were separated by liquid chromatography on DEAE-Sepharose in order to isolate the two major electrophoretic components.
- 2.2. The chromatographic fraction I (electrophoretically slow anodic) showed no Bohr effect and no nucleoside triphosphate modulation.
- 3.3. The chromatographic fraction III (electrophoretically fast anodic) showed a normal Bohr effect and addition of nucleoside triphosphate decreased oxygen affinity but did not alter the Bohr effect.
- 4.4. The whole hemolysate showed a normal Bohr effect and phosphate modulation altered both Bohr effect and oxygen affinity.
- 5.5. No or little difference between the effect of adenosine or guanosine triphosphates on hemoglobin function was observed.
9.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(1):189-193
- 1. Hemolysates fromHoplias malabaricus andHoplerythrinus unitaeniatus show blurred hemoglobin patterns with three and four bands, respectively, by alkaline disc gel electrophoresis.
- 2. The oxygen affinity of the stripped hemoglobin fromHoplerythrinus is about a third of that fromHoplias; theP50 value ofHoplias Hb is about 1.3 mm Hg (pH 6.9 and 20°C). The addition of 1 mM ATP lowers the oxygen affinity of each hemoglobin 2.6-fold.
- 3. Both hemoglobins show Root and Bohr effects;Δlog P50ΔpH= −0.40 for a stripped hemoglobins for the interval pH 7–8.
- 4. The rate of dissociation of oxygen from each hemoglobin is similar and is kinetically homogeneous with rate constants decreasing from 200–250/sec at pH 6.2 to about 25–26 at pH 7.7 with or without 1 mM ATP.
- 5. The CO combination reaction forHoplias hemoglobin is kinetically heterogeneous at all pH values and forHoplerythrinus hemoglobin below pH 7.5. The fast and slow phases each account for about half the observed reaction. The kinetic heterogeneity is maximal at low pH for both hemoglobins. The fast phase forHoplias hemoglobin is more than twice as fast as that forHoplerythrinus hemoglobins.
10.
《Comparative biochemistry and physiology. A, Comparative physiology》1984,77(4):655-665
- 1.1. An artificial diet, consisting of a dry aggregate of 59 chemical substances, was used to assess the requirements of the sea slater Ligia pallasii for vitamins, carbohydrates, fatty acids, cholesterol and minerals.
- 2.2. Good growth and survival of L. pallasii was obtained on the diet, comparable to that on seaweeds and to that shown by a field population.
- 3.3. No dietary requirements for vitamins, fatty acids or cholesterol were shown for periods of 40 weeks or more for L. pallasii.
- 4.4. Carbohydrates were shown to be required by L. pallasii in its diet, in the order: starch, lactose > maltose, glucose > sucrose, cellulose.
- 5.5. Dietary requirements for minerals were, in order: calcium, magnesium, phosphorus > copper, nickel, zinc > iron, manganese, sulphur > iodine, silicon.
- 6.6. The results are discussed in relation to the role of gut bacteria in supplying required nutrients to their isopod hosts and the enhancement of this process through coprophagic behaviour.
11.
《The International journal of biochemistry》1993,25(5):661-664
- 1.1. Analysis of the Soret spectra of hemoglobins A, S and F has been used to determine the extent of heme exposure and release from these hemoglobins in the presence of several solvent perturbants.
- 2.2. Oxyhemoglobin S unfolding in the presence of either urea or propyl urea resulted in greater heme exposure and release than either oxyhemoglobins A or F.
- 3.3. Methemoglobin formation resulted in lower denaturation midpoints for each hemoglobin compared to the reduced oxyhemoglobin state; methemoglobin F had the lowest denaturation midpoint under isothermal denaturing conditions.
- 4.4. Rate of heme exposure was greater for oxyhemoglobin S than oxyhemoglobin A in the presence of 200 μM the anionic detergent sodium dodecyl sulfate.
- 5.5. Evidence for increased levels of heme release in hemoglobin S may be related to the greater tendency of sickled red cell membranes to undergo lipid oxidation.
12.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(1):115-124
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- 1.The Root effect was measured in hemolysates from representatives of 56 genera of Amazonianfishes.
- 2.Hemolysates from several species of air-breathing fishes were found to have Root effects, contraryto published hypotheses.
- 3.Hemolysates from Potamotrygon, a freshwater ray, exhibit a Root effect under our experimental conditions.
- 4.The pattern of Root effect distribution correlates positively with the distribution of choroid retiamirabile and swimbladders, but not with the distribution of swimbladder retia mirabile; it is proposed that the former is the more primitive structure which is associated with the origin of Root effect hemoglobins
- 5.Some of the fish hemoglobins differ spectrally from one another. The positions of the absorptionmaxima of the deoxyhemoglobins range from 553 nm (Lepidosiren paradoxa and Potamotrygon sp.) to 560 nm (Plagioscion)
- 6.Occurrence of Root effects is not correlated with the complexity of the hemoglobin electrophoreticpattern, although several species are found to have multiple hemoglobin systems in which the Root effect is restricted to certain components.
13.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1978,59(3):463-469
- 1.1. The respiratory pigment found in the vascular fluid of Serpula vermicularis appears to be homogeneous with respect to molecular weight (3 × 106), charge (pl = 5.1) and high pH dissociation properties.
- 2.2. Serpula pigment contains one iron per 24,700 g protein with 60% of the iron present as chlorocruoroheme and 40% as heme. This ratio of chlorocruoroheme to heme was found in worms ranging in weight from about 50 to 500 mg.
- 3.3. The pigment is composed of at least three subunits with molecular weights in sodium dodecyl sulfate (SDS) of 13,300, 14,700 and 17,500. The amino acid composition of this pigment is similar to those of other annelid extracellular hemoglobins and chlorocruorins.
- 4.4. Preliminary oxygen equilibrium experiments show that the heme oxygen binding site may combine with oxygen in a manner different from the chlorocruoroheme oxygen binding site.
- 5.5. These results are discussed with respect to possible structures of S. vermicularis pigment, its relationships to other annelid pigments and its function.
14.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1980,65(1):183-185
The dissociation of the extracellular chlorocruorin of Potamilla leptochaeta was investigated by polyacrylamide gel electrophoresis (PAGE) in the presence of sodium dodecyl sulfate (SDS).
- 1.1. The unreduced chlorocruorin dissociated into three subunits with molecular masses of 15,000 (1), 30,000 (2) and 65,000 (3); reduced chlorocruorin provided one broad band of molecular mass 14,000 ± 2000.
- 2.2. Reelectrophoresis of each of the three subunits in the presence of 2-mercaptoethanol provided one broad band having a molecular mass of about 13,000 ± 2000.
- 3.3. It is proposed that Potamilla chlorocruorin consists of interchain disulfide-bonded dimers and tetramers of polypeptide chains of ca. 14,000 ± 2000.
- 4.4. Comparison of the subunit relationships observed in annelid extracellular hemoglobins with those seen in chlorocruorins suggests that there are differences between the two molecules, insofar as aggregation of the smallest subunit is concerned: although it associates into dimers and trimers in hemoglobins, it forms dimers and tetramers in chlorocruorins.
15.
《Comparative biochemistry and physiology. A, Comparative physiology》1986,83(3):507-513
- 1.1. Hatching Caretta caretta may lose up to 12% of their initial hatched weight from water loss during emergence from the nest.
- 2.2. After subsequent osmotic and excretory water loss in sea water, hatchlings will drink sea water (166 μl 100 g−1 hr−1) and return to their initial weight within 10–15 days, without feeding.
- 3.3. There were no significant changes in plasma osmolarity or sodium levels over this period.
- 4.4. This osmoregulatory strategy is in marked contrast to that seen in the estuarine crocodile, Crocodylus porosus.
16.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1990,95(2):291-294
- 1.1. d-Alanine has been found in appreciable amounts in the eggs and embryos of the sea urchin Paracentrotus lividus.
- 2.2. The content of d-alanine, expressed as pmol/egg or embryo, is 1.32 in the egg, 0.81 in the blastula, 0.54 in the gastrula and 0.60 in the pluteus.
- 3.3. The percentage of d-alanine with respect to the total alanine (d + l) decreases during embryonic development.
- 4.4. d-Amino acid oxidase, d-alanine transaminase and d-alanine racemase activities were found neither in eggs nor in embryos.
- 5.5. Therefore, it does not appear likely that d-alanine is subject to oxidative metabolism.
- 6.6. The decrease in this d-amino acid during development may be due to its utilization in the synthesis of a more complex molecule.
17.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(1):179-183
- 1. Oxygen equilibria ofHypostomus andPterygoplichthys hemoglobins and their sensitivities to the erythrocytic nucleotide triphosphates (NTP), ATP and guanosine triphosphate (GTP) are studied to investigate the mechanisms by which blood adapts to air- and water-breathing (cf. Weberet al., 1979).
- 2. Hemoglobins of both species are heterogeneous. All hemoglobin fractions isolated by iso-electric focusing reveal a high sensitivity to NTP, but GTP depresses O2 affinity about twice as effectively as ATP. A cathodal hemoglobin component with a reversed Bohr effect was found inPterygoplichthys but not inHypostomus.
- 3. The data are discussed in relation to thein vivo cofactor modulation of blood O2 affinity and the adaptive significance of functional heterogeneity of fish hemoglobins.
18.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1991,98(3):579-586
- 1.1. The locust vitellogenin (VTG) receptor which is embedded in oocyte plasma membranes is a glycoprotein.
- 2.2. With various lectins oligosaccharide units have been identified, among them neuraminic acid linked to Gal or GalNAc, mannose chains, Gal linked to GalNAc or GlcNAc and fucose linked to GlcNAc.
- 3.3. With specific enzymes it could be shown that mannose and most other oligosaccharides are O-linked while others like fucose are N-linked.
- 4.4. Enzymatic removal of all O-linked carbohydrates resulted in a drop of the molecular mass of the receptor protein from 200,000 to 110,000.
- 5.5. A total of N- and O-linked oligosaccharides of 54% was calculated.
- 6.6. The isoelectric point of the receptor was found to be at pH 3.4 increasing slightly after removal of neuraminic acid.
- 7.7. Removal of neuraminic acids destroyed the binding ability for VTG.
19.
《Comparative biochemistry and physiology. A, Comparative physiology》1991,98(2):455-460
- 1.1. In brush border membrane vesicles isolated from eel kidneys, adapted either to sea water or freshwater environments, a Na+/H+ antiporter is present.
- 2.2. Using a calibration plot it is possible to evaluate the amount of protons that this antiporter can accumulate inside the vesicular space.
- 3.3. The activity of the antiporter seems to be affected by the salinity of the water; it is higher in animals adapted to seawater.
- 4.4. This adaptation seems to occur by a Jmax regulation of the antiporter.
20.
《Comparative biochemistry and physiology. A, Comparative physiology》1989,92(4):535-539
- 1.1. The oxygen consumption of red and green Carcinus in normoxic and hypoxic sea water was determined, using an oxygen electrode in a sealed respirometer.
- 2.2. The red crabs had significantly higher “excited” oxygen uptake rates and a lower ability to compensate for hypoxia than the green crabs.
- 3.3. Red Carcinus display an emersion response to declining oxygen at lower oxygen tensions than the green crabs.
- 4.4. Mortality of red crabs exposed to prolonged anoxia was much greater.
- 5.5. The relationship of these findings to the zonation of the two colour forms on the shore is discussed.