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1.
The hemoglobin of the Giant Otter (Pteronura brasiliensis, Carnivora) contains only one component. The complete primary structures of the alpha- and beta-chains are presented. The globin chains were separated by high-performance liquid chromatography and the sequences determined by automatic liquid- and gas-phase Edman degradation of the chains and their tryptic peptides. The alpha-chains show 18 and the beta-chains 12 exchanges compared with human alpha- and beta-chains, respectively. In the alpha-chains, two substitutions involve alpha 1/beta 1-contacts and one a heme-contact. In the beta-chains one alpha 1/beta 1-, one alpha 1/beta 2- and one heme-contact are exchanged. The alpha- and beta-chains of the Giant Otter are compared to those of the Common Otter and other Carnivora hemoglobins.  相似文献   

2.
The hemoglobin of the Common Otter (Lutra lutra, Carnivora) contains only one component. The complete primary structures of the alpha- and beta-chains are presented. They were separated by high-performance liquid chromatography and the sequences determined by automatic liquid and gas-phase Edman degradation of the chains and their tryptic peptides. The alpha-chains show 18 and the beta-chains 13 substitutions compared to human alpha- and beta-chains, respectively. In the alpha-chains one heme- and two alpha 1/beta 1-contacts are exchanged. In the beta-chains the replacements involve one heme-, one alpha 1/beta 1-, and one alpha 1/beta 2-contact. The alpha- and beta-chains of the Common Otter are compared to those of other Carnivora hemoglobins. The unexpected low number of substitutions between Common Otter hemoglobin and that of Lesser Panda as well as of Harbor Seal is discussed.  相似文献   

3.
The complete primary structure of the hemoglobin from the Pallid Bat (Antrozous pallidus, Microchiroptera) is presented. This hemoglobin consists of two components with identical amino-acid sequences, differing, however, in the N-terminus which is formylated in 12.5% of the beta-chains. The alpha- and beta-chains were separated by reversed phase high performance liquid chromatography. The sequences of both chains were established by automatic Edman degradation with the film technique or gas phase method using the native chains and the tryptic peptides. The formylation of a part of the N-terminal peptide of the beta-chains was determined by mass spectrometric examination. Compared to the corresponding human chains we found 14 substitutions in the alpha-chains and 21 in the beta-chains. One substitution in the alpha-chains and three in the beta-chains are involved in alpha 1/beta 1-contacts. Among these the exchange beta 123(H1)Thr----Cys is unusual because cysteine was so far not found in this position of mammalian beta-chains. Compared to the hemoglobin of Myotis velifer, another representative of the family Vespertilionidae, 5 residues are replaced in the alpha-chains and 18 in the beta-chains.  相似文献   

4.
The hemoglobin of Weddell Seal (Leptonychotes weddelli, Pinnipedia) comprises two components with identical beta-chains. The alpha-chains differ in positions 15 (Gly/Asp) and 57 (Ala/Thr). We present the primary structure of the chains which have been separated by reversed-phase high-performance liquid chromatography. The sequences have been determined by automatic Edman-degradation with the film-technique or the gas-phase method, using the native chains and the tryptic peptides of the oxidized chains. Compared to the corresponding human chains we found 22 substitutions in the alpha-chains and 14 in the beta-chains. In the alpha-chains exchanges involve one heme- and three alpha 1/beta 1-contacts. In the beta-chains one heme contact, one alpha 1/beta 1- and one alpha 1/beta 2-contacts are substituted. The sequences are compared to those of other Pinnipedia and Arctoidea hemoglobins.  相似文献   

5.
The hemoglobin of the ground squirrel Spermophilus townsendii consists of two components which are present in a ratio of ca. 2:1. The two hemoglobins have identical alpha-chains, but differ in their beta-chains. We present the primary structures of the alpha- and the two beta-globin chains. Following chain separation by chromatography on carboxymethyl-cellulose CM-52, the amino-acid sequences were established by automatic Edman degradation of the globin chains and the tryptic peptides, as well as of a peptide obtained by acid hydrolysis of the Asp-Pro bond of the beta-chains. The two beta-chains differ by only one amino-acid residue, Ala being present in the main and Asp in the minor component in position 58 (E2). The comparison with human hemoglobin showed only 14 exchanges in the alpha-chains but 33 in the beta-chains. Whereas no contact positions are affected in the alpha-chains, we found four such substitutions in the beta-chains, including one heme contact, two alpha 1/beta 1-contacts, and one alpha 1/beta 2-contact. It seems however, that the substitution found in the beta-chains has no effect on the oxygen affinity.  相似文献   

6.
The hemoglobin of the European marmot Marmota marmota marmota has been found to consist of only one component. In this work, we are presenting its primary structure. The globin chains have been separated by high performance liquid chromatography and the sequences have been determined by automated Edman degradation of the chains and their tryptic peptides, as well as of the peptide obtained by acid hydrolysis of the Asp-Pro bond in the beta-chains. In the alpha-chains we have found 13 and in the beta-chains 34 exchanges compared with the human alpha- and beta-chains, respectively. The amino acids which are substituted in the alpha-chains are not involved in any contacts, whereas in the beta-chains, one exchange involves a heme contact, two alpha 1/beta 1- and one alpha 1/beta 2-contacts. The functional and evolutionary aspects of these findings are discussed.  相似文献   

7.
The hemoglobin of the Indian false vampire Megaderma lyra contains only one component. In this paper, we are presenting its primary structure. The globin chains were separated by high-performance liquid chromatography and the sequences determined by automatic liquid and gas phase Edman degradation of the chains and their tryptic peptides, as well as of the prolyl-peptides obtained by acid hydrolysis of the Asp-Pro bond in the alpha- and beta-chains. The alpha-chains show 23 and the beta-chains 20 exchanges compared with the human alpha- and beta-chains, respectively. In the alpha-chains, three exchanges involved alpha 1/beta 1 contacts. In the beta-chains one heme-and three alpha 1/beta 1 contacts are exchanged. The functional and systematic aspects of these replacements are discussed.  相似文献   

8.
The hemoglobin of the Brazilian Manatee (Trichechus inunguis, Sirenia) consists of one component. We present the primary structures of the alpha- and beta-chains which have been separated by chromatography on carboxymethyl-cellulose CM-52. The sequences have been determined by automatic Edman degradation with the film technique, using the native chains, tryptic peptides and the C-terminal prolyl-peptide obtained by acid hydrolysis of the Asp-Pro bond of the alpha-chains. Compared to the corresponding human chains we found 27 substitutions in the alpha- as well as in the beta-chains. Three heme contacts and four alpha 1/beta 1 contacts between the subunits are affected by exchanges. The hemoglobin of Trichechus inunguis is compared with those of Elephas maximus, Loxodonta africana, and Procavia habessinica and the monophyletic origin of the superorder Paenungulata is discussed.  相似文献   

9.
The hemoglobin of the Free-Tailed Bat Tadarida brasiliensis (Microchiroptera) comprises two components (Hb I and Hb II) in nearly equal amounts. Both hemoglobins have identical beta-chains, whereas the alpha-chains differ in having glycine (Hb I) or aspartic acid (Hb II) in position 115 (GH3). The components could be isolated by DEAE-Sephacel chromatography and separated into the globin chains by chromatography on carboxymethyl-cellulose CM-52. The sequences have been determined by Edman degradation with the film technique or the gas phase method (the alpha I-chains with the latter method only), using the native chains and tryptic peptides, as well as the C-terminal prolyl-peptide obtained by acid hydrolysis of the Asp-Pro bond in the beta-chains. The comparison with human hemoglobin showed 18 substitutions in the alpha-chains and 24 in the beta-chains. In the alpha-chains one amino-acid exchange involves an alpha 1/beta 1-contact. In the beta-chains one heme contact, three alpha 1/beta 1- and one alpha 1/beta 2-contacts are substituted. A comparison with other chiropteran hemoglobin sequences shows similar distances to Micro- and Megachiroptera. The oxygenation characteristics of the composite hemolysate and the two components, measured in relation to pH, Cl-, and 2,3-bis-phosphoglycerate, are described. The effect of carbon dioxide on oxygen affinity is considerably smaller than that observed in human hemoglobin, which might be an adaptation to life under hypercapnic conditions.  相似文献   

10.
The hemoglobin of the Indian flying fox Cynopterus sphinx contains only one component. In this work, we are presenting its primary structure. The globin chains were separated by high-performance liquid chromatography and the sequences determined by automatic liquid and gas-phase Edman degradation of the chains and their tryptic peptides, as well as of the peptide obtained by acid hydrolysis of the Asp-Pro bond in the beta-chains. The alpha-chains show 14 and the beta-chains 19 exchanges compared with the human alpha- and beta-chains, respectively. In the alpha-chains one amino-acid exchange involves an alpha 1/beta 1 contact. In the beta-chains one heme contact, three alpha 1/beta 1- and one alpha 1/beta 2-contacts are exchanged. The functional and evolutionary aspects of these findings are discussed.  相似文献   

11.
The primary structure of the alpha- and beta-chains of the hemoglobin from the Pacific Walrus (Odobenus rosmarus divergens, Pinnipedia) is presented. Sequence analysis revealed only one hemoglobin component whereas two bands were found in polyacrylamide gel electrophoresis. The globin chains were separated by high-performance liquid chromatography and the sequences determined by automatic liquid- and gas-phase sequencing of the chains and their tryptic peptides. The alpha-chains show 20 and the beta-chains 12 exchanges compared to the corresponding human chains. In the alpha-chains one heme- and two alpha 1/beta 1-contacts were exchanged whereas in the beta-chains one alpha 1/beta 1-, one alpha 1/beta 2-and one heme-contact are substituted. Compared to Harbour Seal (Phoca vitulina) the Walrus hemoglobin shows 9 amino-acid replacements in the alpha-chains and 5 in the beta-chains. The relation between Pinnipedia and Arctoidea is discussed.  相似文献   

12.
The erythrocytes of adult ratel contain two hemoglobin components, with two alpha- and one beta-chains. In this paper, their complete amino acid sequences are presented. The two alpha-chains differ in one residue at position 34 (Ala----Val) only. The primary structure of the chains was determined by sequencing the N-terminal regions (45 steps) and the tryptic peptides after their isolation from the digests by reversed-phase high-performance liquid chromatography. The alignment of these peptides was deduced from homology with other carnivora globins. The alpha-chains show 21 and the beta-chains 11 exchanges compared with human globin chains. In the alpha-chains, one heme- and two alpha 1/beta 1 contacts are exchanged. In the beta-chains there are three exchanges which involve one alpha 1/beta 1-, one alpha 1/beta 2- and one heme-contact. Between the ratel hemoglobin and those of carnivora a high degree of homology was found.  相似文献   

13.
The hemoglobin of the Pale-Throated Three-Toed Sloth (Bradypus tridactylus, Xenarthra) was separated into two components (ratio 4:1) with identical amino-acid analyses for the alpha- and beta-chains. The primary structures of both chains from the major component are given. They could be isolated by chromatography on carboxymethyl cellulose CM-52. The sequences have been determined by automatic Edman degradation of the native chains and their tryptic peptides. The comparison with human hemoglobin showed 27 substitutions in the alpha-chains and 33 in the beta-chains. In the alpha-chains one amino-acid exchange involves an alpha 1/beta 1-contact. In the beta-chains two heme- and four alpha 1/beta 1-contacts are substituted. The hemoglobin of the Sloth is compared to that of the Nine-Banded Armadillo (Dasypus novemcinctus), another representative of the order Xenerthra.  相似文献   

14.
The blood of the Rock-Hopper Penguin contains only one hemoglobin component, corresponding to the Hb A of other birds. The primary structures of the alpha- and beta-chains are presented. The chains were separated by high-performance liquid chromatography and cleaved either enzymatically (alpha) or both enzymatically and chemically (beta). Both the native chains and their peptides were sequenced using liquid and gas phase sequenators. The peptides were aligned using their homology to the sequence of human hemoglobin and other bird hemoglobins. As compared to human hemoglobin, 44 amino-acid replacements are found in the alpha-chains (68% homology) and 47 in the beta-chains (67.8% homology). These exchanges involve seven alpha 1/beta 1 and one alpha 1/beta 2 contact in the alpha-chains, whereas in the beta-chains eight alpha 1/beta 1, one alpha 1/beta 2 and one hem contact are substituted. The influence of these replacements on the structure-function relationships in hemoglobin, as well as their importance for the diving ability of penguins, are discussed.  相似文献   

15.
The primary structure of the alpha- and beta-chains of hemoglobin from spotted hyena (Crocuta crocuta, Hyenidae) is presented. The structure-function relationship is discussed. The separation of the chains directly from hemoglobin was performed by RP-HPLC. After tryptic digestion of the chains, the peptides were isolated by RP-HPLC. Amino-acid sequences were determined by Edman degradation in liquid- and gas-phase sequencers. The alignment of the tryptic peptides was made by homology with human and other Carnivora hemoglobins. The hemoglobin from spotted hyena (Crocuta crocuta) exhibits in its alpha- and beta-chains 22 and 20 exchanges, respectively, compared to human hemoglobin. In the alpha-chains, two alpha 1 beta 1-contacts are exchanged. In the beta-chains five exchanges involve one alpha 1 beta 1-contact, one alpha 1 beta 2-contact, one heme contact, and two 2,3-DPG-binding sites.  相似文献   

16.
Polyacrylamide gel electrophoresis and ion-exchange chromatography revealed one hemoglobin component for vicuna (Lama vicugna) and alpaca (Lama pacos). Following chain separation by chromatography on carboxymethyl-cellulose, the amino-acid sequences were elucidated for the alpha- and beta-chains of both hemoglobins using automatic Edman degradation of the chains and the tryptic peptides. Vicuna and alpaca have identical beta-chains showing no substitutions to llama (Lama glama) either. In the alpha-chains alpaca differs from llama by the exchange of one amino-acid residue: alpha 122(H5)Asp----His. The same substitution is present in vicuna too, but in addition we found two more exchanges: alpha 10(A8)Ile----Val and alpha 130(H13)Ala----Thr. The close relationship between llama and alpaca suggests that they both originate from the wild guanaco, and there is no domesticated form of vicuna. The sequence data show that the higher oxygen affinity in vicuna compared to llama and alpaca must be due to the alpha-chains as the beta-chains are identical. The significance of the substitutions in alpha 122(H5), an alpha 1/beta 1-contact, and alpha 130(H13) is discussed.  相似文献   

17.
The complete primary structure of the hemoglobin from the Mandrill (Mandrillus sphinx, Primates) is presented. This hemoglobin comprises two components in approximately equal amounts (HB I and Hb II). The alpha-chains differ in positions 5 (A3) and 9 (A7) having Ala and Asn in the alpha I-chains and Asp and His in the alpha II-chains. The beta-chains are identical. The components could be separated by DEAE-Sephacel chromatography. The globin chains were obtained by carboxymethylcellulose chromatography or high-performance liquid chromatography. The sequences were established by automatic liquid or gas phase Edman degradation of the chains and their tryptic peptides. The alpha-chains show 9 and 11 and the beta-chains 8 exchanges compared with the corresponding human chains, respectively. In the beta-chains one alpha 1/beta 1- and one alpha 1/beta 2-contact is substituted. A comparison of the primary structures of the Mandrill hemoglobin chains with those of other species of the Cercopithecidae family shows that Mandrillus sphinx should be placed between Cercopithecus and Macaca on one side and Papio, Theropithecus and Cercocebus on the other.  相似文献   

18.
Mole rat (Spalax ehrenbergi) hemoglobin consists of only one component. The complete amino-acid sequence of the alpha- and beta-chains of the species with the diploid chromosome number of 60 is presented. Following chain separation by chromatography on carboxymethyl cellulose CM-52, the primary structures were established by automatic Edman degradation on the chains, on the tryptic peptides, and on a peptide obtained by acid hydrolysis of the Asp-Pro bond in beta-chains. The alignment of the peptides was performed by homology with human alpha- and beta-chains. The comparison showed an exchange of 23 residues in the alpha-chains and 26 in the beta-chains. One substitution in the beta-chains concerns the surrounding of the heme. We found two exchanges in each chain in the alpha 1 beta 1-subunit interface and one in the beta-chain alpha 1 beta 2-contact points. Though all binding sites for 2,3-bisphosphoglycerate are unchanged, the mole rat blood has a high oxygen affinity as a part of adaptation to subterranean life under hypoxia and hypercapnia. A comparison of the sequence with known X-ray models of hemoglobins may give an interpretation of this fact. The primary structure of the mole rat hemoglobin shows more similarities with surface rodents, than with the mole, another small mammal, adapted to hypoxia in subterranean tunnels. The adaptation to hypoxia in mole rat and mole must be due to different mechanisms.  相似文献   

19.
Two types of alpha- and two types of beta-chains are found in the hemoglobin of yak population. The complete amino-acid sequences of the four polypeptide chains were determined. The two alpha-chains differ by two and the two beta-chains by three amino-acid substitutions. The substitution of valine at position 135 in the beta II-chain may be responsible for the high intrinsic oxygen affinity of yak hemoglobin.  相似文献   

20.
Ferret erythrocytes contain two hemoglobins differing only by their alpha-chains. The primary structure of the common beta-chain has been previously described; the complete sequence of the two alpha-chains are reported in this paper. The globin chains were separated by ion-exchange chromatography; the alpha-chains (42 steps), their tryptic peptides as well as the prolyl-peptides were subjected to automatic liquid- and gas-phase Edman degradation. The two alpha-chains are very similar, differing at only one position (Asp15----Gly15). Comparison with human hemoglobin alpha-chain shows 16 and 17 exchanges, for alpha 1 and alpha II chains, respectively; two substitutions involve alpha 1/beta 1 contacts and one the heme contacts. A high degree of homology was noted when the alpha-chains were compared to the corresponding chains of other representatives of the Carnivora order.  相似文献   

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