Susceptibility of erythrocytes from several animal species to Vibrio vulnificus hemolysin

The hemolytic activity of Vibrio vulnificus hemolysin (VVH) against erythrocytes from several animal species (sheep, horse, cow, rabbit, chicken) was investigated. VVH was active against erythrocytes from all species, but the amount of VVH causing 50% hemolysis under identical conditions (hemolytic susceptibility to VVH) differed. The degree of 125I-labeled VVH (125I-VVH) binding to each erythrocyte species correlated with the susceptibility of the cells to hemolysis. However, marked differences in the binding ability of 125I-VVH were not observed against liposomes constructed with lipids from each erythrocyte membrane. On the other hand, release of hemoglobin (Hb) differed for each of the erythrocyte species despite administration of approximately the same hemolytic VVH concentration to each species. Furthermore, under hypotonic conditions, the stability of each erythrocyte species varied markedly; the more susceptible the erythrocyte to VVH, the more unstable it was under such conditions. These results, therefore, suggest that the susceptibility of erythrocytes to VVH may be closely associated with the binding ability of VVH and erythrocyte membrane stability.     

Inhibition of trypsins and chymotrypsins from different animal species: a comparative study

The effect of 3 purified trypsin inhibitors and 4 legume seed extracts on teh trypsins and chymotrypsins of the activated pancreata of 11 animal species, including man, was measured. The activation was performed by either homologous enterokinase or by bovine trypsin. Several trypsinogens were not activated by the latter. Rabbit trypsin was the most sensitive to all inhibitor preparations, while the human trypsin was the most resistant, except to the black bean extract. The response of the chymotrypsins was more variable and those of capybara and rabbit showed extreme sensitivity. Considerable differences between the extracts of black and white garden beans, both Phaseolus vulgaris, with respect to their reactivity toward different animal enzymes were detected. No relation between relative pancreas weight and susceptibility toward soybean trypsin inhibitor could be observed.     

Peripheral enkephalin hydrolysis in different animal species: A comparative study

Using column and thin layer chromatography, plasma hydrolysis of leu-enkephalin has been studied in man and several laboratory animals. The hydrolysis kinetics determined in the various species examined are considerably different. In addition, also the enzyme forms evidentiated, their molecular weight distribution and relative ratios have been found to vary greatly in the animals under test. Our data suggest that the widely different hydrolysis kinetics reported by various authors are attributable to the differences between species, rather than to differences in the analytical techniques employed.     

A comparative study of superoxide dismutase in various animal species

1. Superoxide dismutase activity has been determined in liver homogenates of five species. There were no significant differences in the activities of the enzyme in the rat, rainbow lizard, wall gecko and chicken. The activity was significantly lower in the fish. 2. The order of activity of the enzyme in the organs/tissues of the rat was liver greater than kidney greater than heart greater than skeletal muscle greater than brain greater than lung greater than spleen greater than spinal cord greater than retina greater than pancrease greater than lens greater than small intestine. 3. Inhibition studies with cyanide showed that the enzyme in the liver of the various animal species was inhibited by cyanide. 4. The developmental pattern for the enzyme showed no significant changes in the liver of the rat from birth and up to 7 weeks after. However, the activity increased at about 8 weeks and remained constant to adult life.     

Plasma membrane nadh dehydrogenase and Ca2+-dependent potassium transport in erythrocytes of several animal species

Ca2+-dependent K+ transport and plasma membrane NADH dehydrogenase activities have been studied in several 'high-K+' (human, rabbit and guinea pig) and 'low-K+' (dog, cat and sheep) erythrocytes. All the species except sheep showed Ca2+-dependent K+ transport. NADH-ferricyanide reductase was detected in all the species and showed positive correlation with the flavin contents of the membranes. NADH-cytochrome c reductase was very low or absent in dog, sheep and guinea pig membranes. No correlation was found between NADH dehydrogenase and Ca2+-dependent K+ channel activities in the species studied. Nor were any of the above activities correlated with (Na+ + K+)-ATPase activity.     

Electron transfer function versus oxygen delivery: a comparative study for several hexacoordinated globins across the animal kingdom

Caenorhabditis elegans globin GLB-26 (expressed from gene T22C1.2) has been studied in comparison with human neuroglobin (Ngb) and cytoglobin (Cygb) for its electron transfer properties. GLB-26 exhibits no reversible binding for O(2) and a relatively low CO affinity compared to myoglobin-like globins. These differences arise from its mechanism of gaseous ligand binding since the heme iron of GLB-26 is strongly hexacoordinated in the absence of external ligands; the replacement of this internal ligand, probably the E7 distal histidine, is required before binding of CO or O(2) as for Ngb and Cygb. Interestingly the ferrous bis-histidyl GLB-26 and Ngb, another strongly hexacoordinated globin, can transfer an electron to cytochrome c (Cyt-c) at a high bimolecular rate, comparable to those of inter-protein electron transfer in mitochondria. In addition, GLB-26 displays an unexpectedly rapid oxidation of the ferrous His-Fe-His complex without O(2) actually binding to the iron atom, since the heme is oxidized by O(2) faster than the time for distal histidine dissociation. These efficient mechanisms for electron transfer could indicate a family of hexacoordinated globin which are functionally different from that of pentacoordinated globins.     

Plasma membrane NADH dehydrogenase and Ca2+-dependent potassium transport in erythrocytes of several animal species

Ca²⁺-dependent K⁺ transport and plasma membrane NADH dehydrogenase activities have been studied in several ‘high-K⁺’ (human, rabbit and guinea pig) and ‘low-K⁺’ (dog, cat and sheep) erythrocytes. All the species except sheep showed Ca²⁺-dependent K⁺ transport. NADH-ferricyanide reductase was detected in all the species and showed positive correlation with the flavin contents of the membranes. NADH-cytochrome $\text{c}$ reductase was very low or absent in dog, sheep and guinea pig membranes. No correlation was found between NADH dehydrogenase and Ca²⁺-dependent K⁺ channel activities in the species studied. Nor were any of the above activities correlated with $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ activity.     

Contribution of glycolipids to species-specific antigens on erythrocytes of several animal species as to recognition of antigens with rabbit anti-glycolipids and anti-erythrocyte antisera

Because anti-glycolipid antibodies are involved in the onset of several neurological diseases, the reactivity of glycolipids on erythrocytes and the probability of generating the antibodies were determined to clarify the contribution of glycolipids as antigens. Anti-erythrocyte antisera reacted with the following glycolipids in a species-specific manner, i.e. blood group A-active glycolipid for man, Forssman glycolipid for sheep, Gg₃Cer for guinea pig, and Gg₄Cer and fucosyl GM1 for rat, and the hemolytic activities of the anti-erythrocyte antisera were attenuated by absorption of the antisera with liposomes prepared from the lipids of erythrocytes to the following levels, 94.5% for man, 24.5% for sheep, 17.5% for guinea pig, and 54.5% for rat. These species-specific glycolipids on erythrocytes reacted well with the respective anti-glycolipid antisera, but Gb₄Cer in man and GM1 in rat were shown to be cryptic on immunization with erythrocytes, indicating that the contribution of glycolipids as erythrocyte antigens differs among animal species. The glycolipid nomenclature is based on the recommendations of the IUPAC-IUB Commission on Biochemical Nomenclature [1]. The ganglioside nomenclature of Svennerholm is employed throughout [2].     

The distribution of neuropeptides in the ocular tissues of several mammals: a comparative study.

1. The distribution of several neuropeptides (vasoactive intestinal peptide, substance P, somatostatin and neurotensin) was assessed in ocular tissues from the cow, sheep, rabbit and rat. 2. Vasoactive intestinal peptide was most abundant in the choroid and sclera in all species except the rat. Substance P was most abundant in the retina of cow and rat and in the iris/ciliary body of sheep and rabbit. Somatostatin and neurotensin were most abundant in the retina of all species examined. 3. Regulatory peptides thus display distinct regional distributions within the ocular tissues of a single species of mammal and, in addition, exhibit interspecific variation.