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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.
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2.
  • 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.
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3.
  • 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.
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4.
  • 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.
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5.
  • 1.1. Each of the four major globins found in the erythrocytic hemoglobins of the sea cucumber Molpadia arenicola have been shown to be N-acetylated.
  • 2.2. The hemoglobins from the sea cucumbers M. oölitica, Cucumaria rubra, Thyonella pervicax and Pentacta pygnaea were also shown to be blocked at the N-terminus.
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6.
  • 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.
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7.
  • 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.
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8.
  • 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.
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9.
o
  1. 1.The Root effect was measured in hemolysates from representatives of 56 genera of Amazonianfishes.
  2. 2.Hemolysates from several species of air-breathing fishes were found to have Root effects, contraryto published hypotheses.
  3. 3.Hemolysates from Potamotrygon, a freshwater ray, exhibit a Root effect under our experimental conditions.
  4. 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. 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. 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.
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10.
  • 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.
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11.
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.
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12.
  • 1.1. Albumin purified from rhesus monkey (MSA) shows immunological cross-reactivity with human serum albumin (HSA) by RIA.
  • 2.2. The amino-terminal sequence of MSA shows a high degree of homology to HSA.
  • 3.3. Thirty minutes after injection of radioactive leucine directly into the portal vein, albumin was purified chemically from the liver, kidneys and serum.
  • 4.4. At this time, 15% of the label was incorporated into liver homogenate protein.
  • 5.5. A highly labelled immunoreactive albumin form was purified from liver to constant specific radioactivity and separated from tissue and serum albumin.
  • 6.6. The specific radioactivity of this proalbumin was 36-times higher than the specific radioactivity of albumin in liver tissue.
  • 7.7. These similarities to HSA suggest that this non human primate species can serve as a useful model of human albumin synthesis in vivo.
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13.
  • 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
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14.
  • 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.
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15.
  • 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.
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16.
  • 1. The two hemoglobins, Hb I and II, of the obligate air-breathing catfish,Hoplosternum littorale have been isolated.
  • 2. The unfractionated stripped hemoglobin has a high oxygen affinity, a normal alkaline Bohr effect, and a Root effect.
  • 3. Both the Bohr and Root effects are enhanced by 1 mM ATP.
  • 4. Stripped Hb I has a relatively high oxygen affinity, a reversed Bohr effect between pH 6.0 and 8.0 (Δlog P502DpH> 0), but no Root effect. Addition of 1 mM ATP to Hb I causes a marked reduction in the oxygen affinity, a change to a normal alkaline Bohr effect (Δlog P50ΔpH< 0), but no Root effect.
  • 5. Stripped Hb II has a lower oxygen affinity at low pH and a higher oxygen affinity at high pH than does Hb I. Hb II shows a large alkaline Bohr effect which is only slightly increased by 1 mM ATP and a Root effect at low pH which is enhanced by 1 mM ATP.
  • 6. The observed rates of O2 dissociation and of CO combination with Hbs I and II show differences which parallel those observed in the oxygen equilibrium measurements.
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17.
  • 1.1. To understand the physiological roles of the 90-kDa stress protein (HSP90), we investigated the heparin- and antibody-binding domains of the protein.
  • 2.2. For heparin-binding sites, HSP90 was digested completely with trypsin, and the digests were applied to a heparin-Sepharose column and eluted with 1.0 M NaCl, followed by 8.0 M urea.
  • 3.3. Each elutant was purified by a reverse-phase C18 column.
  • 4.4. Two peptides from the NaCl-eluted fraction and no peptide from the urea-eluted fraction were purified.
  • 5.5. The purified peptides were sequenced by an automated peptide sequencer.
  • 6.6. One of the heparin-binding sites was present between Leu-362 and Arg-365; another was present between Leu-645 and Lys-648.
  • 7.7. These two peptides were basic and considerably hydrophilic.
  • 8.8. For antibody-binding sites, HSP90 was mildly digested with trypsin, electrophoresed on SDS-polyacrylamide gels and transferred to PVDF membranes.
  • 9.9. The four bound of the trypsin fragments could be sequenced with a peptide sequencer.
  • 10.10. There was only one antibody-binding peptide, 38 kDa, starting from Pro-2. The others showed no cross-reactivity with the antibody and started from Leu-283.
  • 11.11. Therefore, the epitopes of HSP90 are present between Pro-2 and Leu-282.
  • 12.12. The heparin-binding sites are present from the middle region of the HSP90 molecule, and the antigen sites are at the N-terminal domain.
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18.
  • 1.1. The oxygen equilibria of the multiple hemoglobin of the fry and adult life stages of coho salmon (Oncorhynchus kisutch) were investigated. Components A 6–8 comprise 50–55% and >95% of the total hemoglobins of coho adults and fry respectively.
  • 2.2. Fry hemoglobins exhibited a high oxygen affinity (P50 = 3.9 mm Hg at 9.8°C, pH 8.5), a very large Bohr shift (ø = Δlog 50/ΔpH = −1.729 at pH 7.1–7.5) which was non-linear in the pH range 6.8–8.5 and a large heat of oxygenation (ΔH = −20.8 kcal/mol).
  • 3.3. Adult hemoglobins, however, exhibited a moderate oxygen affinity (P50 = 14.0 mm Hg at 9.8°C, pH 8.2), a very small linear Bohr shift (ø = −0.172 at pH 7.0 −8.2) and a low heat of oxygenation (ΔH = −5.6- −7.5kcal/mol). Adenosine triphosphate had only minor influence on the oxygenation characteristics of adult heolyzates.
  • 4.4. The results are discussed in terms of functional adaptation to environmental stresses and metabolic requirements.
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19.
This paper comments on: Low, B. S., Alexander, R. D., and Noonan, K.M. Human hips, breast, and buttocks: Is fat deceptive? Ethology and Sociobiology 8: 249-247, 1987. In it I argue that:
  • 1.1. Sexual selection has probably not been the most important selection pressure on
  • 2.female human body shape.
  • 3.2. Male humans in different cultures find different aspects of the female body attractive
  • 4.and therefore are unlikely to have exerted consistent directional sexual selection on
  • 5.the female body.
  • 6.3. Breast size is not correlated with lactation success.
  • 7.4. Visible hip width is not correlated with parturition success.
  • 8.5. Women would lower their fitness if they tried to deceive men about their internal
  • 9.pelvic dimensions.
  • 10.6. There are many alternative hypothesis to explain the existence of fat onwomen's
  • 11.breast, hips, and buttocks.
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20.
  • 1. We have measured the temperature dependence of the oxygen equilibria of blood and hemoglobin solutions from four neotropical and three temperate zone fishes.
  • 2. Significant differences exist in the heats of oxygenation of the bloods but not the hemoglobin solutions from different species.
  • 3. The differences in thermal sensitivity of the oxygenation of the bloods appear to depend on differences in intracellular pH, organic phosphates and other ligand-linked variables and not the intrinsic enthalpies of the oxygenation of the hemoglobins themselves.
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