Functional properties of the two major hemoglobin components from Leporinus friderici (Pisces)

• 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.

     

Oxygen binding by the hemocyanin of Busycon canaliculatum

• 1.1. This study examined the effect of the monoamines dopamine and octopamine, as well as tyrosine on the oxygen affinity and cooperativity of oxygen binding by the hemocyanin of the marine gastropod Busycon canaliculatum. The effect of temperature on hemocyanin oxygen affinity was also examined.
• 2.2. Freezing Busycon hemocyanin did not affect the binding of oxygen.
• 3.3. Dopamine, octopamine and tyrosine had no significant effect on the oxygen affinity or cooperativity of oxygen binding by the hemocyanin of B. canaliculatum.
• 4.4. It was concluded that Busycon hemocyanin either has no binding sites for the two monoamines or for tyrosine, or that binding of the molecules has no functional significance.
• 5.5. Both temperature sensitivity and affinity of hemocyanin-oxygen binding were similar to values previously reported for hemocyanin of Busycon from other localities.

     

Hemoglobin-containing cells of Neodasys (gastrotricha,chaetonotida)—II. Respiratory significance

• 1.1. The properties of the intracellular hemoglobin of Neodasys sp. are described and the utility of the hemoglobin in oxygen transport and storage is considered.
• 2.2. The hemoglobin is located in immobile cells which occupy 14% of the total body volume. Heme concentration in these cells was 18.5 mM and the oxygen p50 (in vivo) was approximately 1.0 mmHg.
• 3.3. It is argued that oxygen storage is the most likely function of Neodasys hemoglobin. A simple geometric argument indicates that body wall oxygen transport is not greatly improved by facilitation.
• 4.4. Respiratory function in Neodasys is compared with that in a related gastrotrich, Turbanella, which is morphologically similar and is sympatrie, but does not possess hemoglobin.

     

Multiple hemoglobins in Triturus cristatus: their study by analytical isoelectrofocusing

• 1.1. Electrophoretic separation of the hemoglobin of healthy adult Triturus cristatus reveals four components.
• 2.2. Isoelectric focusing of the samee hemolysates in various commercial ampholytes of different chemical composition and pH range results in the separation of eight individual hemoglobin bands.
• 3.3. The bands obtained by electrophoresis are not homogeneous as revealed by individual gel electrofocusing. They finally separate into the same eight components, as in the whole hemolysate.
• 4.4. From the above findings it is concluded that this species has not four but eight individual hemoglobin molecular forms.
• 5.5. Our results demonstrate lack of hemoglobin polymorphism in this species.

     

Hyperosmotic properties of the fluids of the perivisceral coelom and water vascular system of starfish kept under stable conditions

• 1.1. Osmotic measurements were made on the perivisceral coelomic and water vascular fluids of 4 species of northwest Pacific starfish and their stable sea-water media.
• 2.2. Mean levels of both fluids were hyperosmotic in every species, often at statistically significant levels.
• 3.3. For all species combined, mean hyperosmolality (mosmol/kg ± SE) of perivisceral coelomic fluid was 1.49 ± 0.17, and water vascular fluid 6.07 ± 0.74.
• 4.4. The hyperosmotic nature of these fluids contributes to water balance, working in conjunction with madreporitic inflow and other factors.

     

Comparative study of hemoglobins from different Artemia populations. The influence of temperature on the oxygen equilibria

• 1.1. The P50 values of extracellular hemoglobin (Hb) of five Artemia populations from different geographical origin are affected by temperature.
• 2.2. The free oxygen binding energy is high for all the populations (ΔH between −34.7 and −56.2kj/mol).
• 3.3. A possible correlation between thermal sensitivity of Hb and the ambient temperature of the habitat must be considered very carefully.
• 4.4. The occurence of different quantities of Hb1 (αα chains) Hb2 (αβ chains) and Hb3 (ββ chains) in the different populations possibly influences thermal sensitivity.

     

The digestive enzymes of the pacific brown shrimp Penaeus californiensis.: I—Properties of amylase activity in the digestive tract

• 1.1. Crude extract of the whole digestive tract from the brown shrimp (P. californiensis) was investigated for digestive amylase activity.
• 2.2. Considerable amylase activity was found at pH 6.5–8.0, with optimum pH at around 7.5.
• 3.3. Optimum temperature was found between 30–40°C, similar to amylases from other crustaceans.
• 4.4. Amylase activity was highly halotolerant, having 50% maximum activity at 3 M NaCl.
• 5.5. Maximum amylase activity was found at 0.01 M NaCl.
• 6.6. Amylase activity was partially inhibited by the divalent ions Hg²⁺, Zn²⁺, Cu²⁺ and Cr²⁺.
• 7.7. Mg²⁺ and Ca²⁺ ions seemed to enhance amylase activity.

     

Purification and characterization of elastase from the pyloric caeca of rainbow trout (Oncorhynchus mykiss)

• 1.1. An elastase-like enzyme was purified from the pyloric caeca of rainbow trout by hydrophobic interaction, cation exchange and gel-filtration chromatography.
• 2.2. The approximate molecular weight of the elastase was 27 kDa and the isoelectric point was remarkably basic.
• 3.3. The pH optimum of this enzyme was 8.0, when assayed with Succinyl-Ala-Ala-Ala-p-Nitroanilide.
• 4.4. When assayed with Succinyl-Ala-Ala-Ala-p-Nitroanilide, the enzyme activity had a temperature optimum of 45°C, and the enzyme was stable up to this temperature.
• 5.5. The trout elastase exhibited a higher specific activity than porcine elastase against Succinyl-Ala-Ala-Ala-p-Nitroanilide and elastin-orcein.
• 6.6. The trout elastase was inhibited by elastatinal, PMSF, TPCK, SBTI and Bowman-Birk inhibitor.

     

The purification of kallikrein from human whole saliva

• 1.1. A quick and simple procedure is described for purifying kallikrein from human whole saliva. The enzyme has been purified about 2700-fold with a yield of approx. 30%.
• 2.2. The procedure is based on the immediate fractionation of saliva by ion exchange chromatography. This is followed by a combination of affinity and high performance liquid chromatography.
• 3.3. The results indicate that another protein component binds to the enzyme at pH 8.0.
• 4.4. The homogeneity of the enzyme has been demonstrated by gel electrophoresis in the absence as well as in the presence of sodium dodecylsulfate.
• 5.5. A mol. wt of 40,100±1800 has been calculated from gel electrophores is experiments.
• 6.6. Sedimentation equilibrium in an analytical ultracentrifuge gave a mol. wt of 39,700.
• 7.7. The amino acid composition has been determined and it confirms that the enzyme has a low isoelectric point.
• 8.8. The presence of tryptophan has been demonstrated by absorption and fluorescence spectroscopy.

     

The oxygen consumption rates of three gastrotrichs

• 1.1. The oxygen consumption rates for three sympatric species of marine gastrotrichs (anatomically similar, except that one contains hemoglobin) were measured with a Cartesian diver microrespirometer.
• 2.2. The rates for the two species without hemoglobin, Turbanella ocellata and Dolichodasys carolinensis, were 307.2 μl O₂ g⁻¹ hr⁻¹ and 108.0 μl O₂ g⁻¹ hr⁻¹, respectively, while the rate for the hemoglobin-containing species, Neodasys, was 208.9 μl O₂ g⁻¹ hr⁻¹.
• 3.3. The possession of hemoglobin by Neodasys (14% by volume) cannot be explained by an unusually high demand for oxygen.
• 4.4. Instead, the hemoglobin may be useful as an oxygen store providing continued aerobic metabolism in anoxic conditions, thus allowing Neodasys to exploit a different niche.

     

In vivo photo-affinity labelling of glutathione receptors mediating the tentacle ball formation,a behavioral response associated with the feeding of Hydra

• 1.1. The tentacle ball formation, a response associated with the feeding of Hydra japonica, with S-(p-azidophenacyl)-glutathione (GSPAP) was reduced upon illumination.
• 2.2. GSPAP did not cause the depression without illumination nor did illumination without GSPAP.
• 3.3. The concentration dependence of the response of the photolabelled animals suggested high and low affinity glutathione receptors. The low affinity receptor may be efficiently tagged with GSPAP upon photolysis.

     

Adaptative features of amazon fishes: Hemoglobins,hematology, intraerythrocytic phosphates and whole blood Bohr effect of Pterygoplichthys multiradiatus (Siluriformes)

• 1.1. Hemoglobin, hematological parameters, intraerythrocytic phosphates and whole blood Bohr effect of Pterygoplichthys multiradiatus, from the Amazon river, were studied in three different conditions: in their natural environment, acclimated to normoxia and acclimated hypoxia conditions.
• 2.2. Nine anodal hemoglobin fractions were detected on starch gel electrophoresis. No qualitative differences in the Hb electrophoretic patterns were detected in the three studied groups.
• 3.3. Hematocrit, hemoglobin concentration, MCV, MCHC and MCH were different among studied conditions.
• 4.4. GTP was almost absent in the blood of animals in natural conditions and acclimated to hypoxia, but was present at a concentration similar to ATP in normoxic acclimated animals.
• 5.5. There is a tendency for higher Hb-O₂ affinity for hypoxic acclimated/acclimatized animals.

     

Oxygen binding characteristics of Artemia hemoglobin domains

• 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.

     

On the purification and characterization of exopeptidases from antarctic krill,Euphausia superba

• 1.1. Two carboxypeptidase-A type of enzymes and two carboxypeptidase-B type of enzymes effecting hydrolysis of Hipp-l-Phe and Hipp-l-Arg respectively, have been purified from E. superba using gel filtration, affinity chromatography and FPLC-anion exchange chromatography. In addition an aminopeptidase has been partly purified.
• 2.2. The carboxypeptidases had mol. wts of 27,000 (carboxypeptidase A) and 31,000 (carboxypeptidase B).
• 3.3. Carboxypeptidase A exhibited a broad pH optimum with a maximum at pH 5.5–6.5, whereas carboxypeptidase B had a more narrow pH-optimum with a maximum at pH 7. The aminopeptidase had an optimum at about pH 8.7.
• 4.4. The carboxypeptidases were inhibited by the chelating agent 1,10-phenanthroline.

     

Changes in composition and proteolytic enzyme activities of artemia during early development

• 1.1. The proximate composition, total and free amino acids, and proteases of Artemia nauplii were determined during early development.
• 2.2. Moisture increased from 71.0% to 80.8%, crude protein decreased from 13.2% to 8.8%, crude fat and ash varied slightly.
• 3.3. The total amino acids decreased. Free amino acids changed in three patterns.
• 4.4. Trypsin, chymotrypsin, carboxypeptidase A, B and cathepsin B and C increased in activity. The activity of trypsin was lower, while cathepsin B and C were the highest.
• 5.5. The protease activities were maximal at pH 7.5 and 8.0, and at 45°C on casein.
• 6.6. The optimal pH for carboxypeptidase A was 4.0, for carboxypeptidase B was 4.5, for trypsin and chymotrypsin were 7.0–7.5. The protease(s) active at pH 9.0–9.5 were to be determined.

     

Echinochrome-A as a bactericidal substance in the coelomic fluid of Echinus esculentus (L.)

• 1.1. The concentrations of echinochrome-A in coelomic fluid from healthy specimens of the sea urchin Echinus esculentus (L.) ranged from 3 to 60 μg/ml, with a geometric mean of 14 μg/ml.
• 2.2. Echinochrome-A (50 μg/ml) dissolved in sea water, with the aid of mammalian proteins as dispersants, was bactericidal or bacteriostatic towards six out of seven strains of marine gram-negative and gram-positive bacteria.
• 3.3. Echinochrome-A is suggested as a major factor in the bactericidal activity of coelomic fluid from E. esculentus.

     

Lipoxygenase of Thermoactinomyces vulgaris,purification and characterization of reaction products

• 1.1. A lipoxygenase preparation was obtained from Thermoactinomyces vulgaris and was purified by affinity chromatography on a linoleyl aminoethyl sepharose column.
• 2.2. Two active fractions were obtained.
• 3.3. The fraction obtained by elution with 100 mM borate buffer pH 9.0 was used in the subsequent work.
• 4.4. Th. vulgaris lipoxygenase oxidized linoleic acid into two products: 13-HPOD and 9-HPOD at a ratio of 44 to 56, respectively.
• 5.5. The identification and characterization of the isomers was done by HPLC, I.R. and mass spectrometry.
• 6.6. When arachidonic acid was used as substrate, 15-HPETE and 15-HETE were found to be the main enzymatic products.

     

Seasonal adaptations in oxygen transport in brown trout Salmo trutta fario

• 1.1. Blood parameters determining oxygen capacity and oxygen affinity were measured in brown trout at different times of the year.
• 2.2. Haematological data indicate a slight decrease in blood oxygen capacity during the warm seasons. 3. Oxygen affinity increases significantly during summer and decreases in winter.
• 3.4. The changes in P₅₀ exhibited a positive correlation with the amount of anodic haemoglobin components, and a negative correlation with the amount of cathodic haemoglobin components.
• 4.5. The changes observed in the [ATP]/[Hb] molar ratio were not correlated with oxygen affinity and gave values near one.
• 5.6. We conclude that the oxygen affinity increase could be a physiological adaptation to oxygen transport during the wanner period. A possible mechanism is discussed.

     

Oxygen binding characteristics of whole-blood and hemoglobin from the snake Thamnophis sirtalis

• 1.1. Oxygen binding capabilities of whole-blood and hemoglobin from the snake Thamnophis sirtalis were analyzed, at different temperatures and with various organic phosphate concentrations.
• 2.2. In whole-blood, the Hb-Hb co-operativity increases at high oxygen saturation, and at high temperatures (20 and 30°C) at low saturations as well. The co-operativity is slightly in excess of 4.
• 3.3. Half-saturation co-operatively in hemoglobin solutions increases significantly (0.2—0.4 units) on addition of ATP, but not when the temperature is raised.

     

S-Adenosyl-l-methionine decarboxylase activities in Mytilus edulis

• 1.1. The activities of S-adenosylmethionine decarboxylase (EC 4.1.1.50) were measured in cell extracts of mantle, hepatopancreas and foot from Mytilus edulis.
• 2.2. The apparent molecular weights of the enzymes estimated by gel filtration chromatography were 65,000 ± 10,000.
• 3.3. The enzymes do not require bivalent cations for catalysis and show optimum pH between 7.0–8.0 in phosphate buffer.
• 4.4. The hepatopancreas enzyme shows different behavior to the other two enzymes against temperature and its activity is strongly inhibited by NH₄⁺.
• 5.5. The apparent K_ms for S-adenosylmethionine were found to be 300, 200 and 250 μM for the hepatopancreas, mantle and foot enzymes, respectively.