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1.
The adult Stump-Tail Monkey (Macaca speciosa) was found to have two major hemoglobin components (Hb 1 and Hb 2) which were separated by carboxymethyl cellulose column chromatography. The tryptic peptides of the alpha and beta chains from the two components were isolated and sequenced. The peptides were aligned based on the homology of their sequences with that of human adult hemoglobin. Only one amino-acid difference was found between the alpha chains from Hb 1 and Hb 2 at the 15th position from the N-terminus. On the other hand, the beta chains from the two hemoglobin components were considered to be identical.  相似文献   

2.
The primary structure of the hemoglobins from Jaguar (Panthera onco) are presented. Electrophoretic separations without and with a dissociating agent revealed the presence of two hemoglobin components, alpha 2 beta I2 and alpha 2 beta II2. The separation of the hemoglobin components was achieved by ion-exchange chromatography. The globin chains were separated by ion-exchange chromatography and also by reversed phase HPLC. The amino-acid sequences of the native chains and peptides were determined by liquid-phase and gas-phase sequencing. N-Acetylserine was detected by FAB-mass spectroscopy as N-terminal group of the beta I chain. The sequences are compared with that of human hemoglobin (Hb A).  相似文献   

3.
alpha and beta chains from adult hemoglobin of the slender loris (Loris tardigradus) were isolated by Amberlite CG-50 column chromatography. After S-aminoethylation, both chains were digested with trypsin and the amino acid sequences of the tryptic peptides obtained were analyzed. Further, the order of these tryptic peptides in each chain was deduced from their homology with the primary structures of alpha and beta chains of human adult hemoglobin. Comparing the primary structures of the alpha and beta chains of adult hemoglobin of the slender loris thus obtained with those of adult hemoglobin of the slow loris, 4 amino acid substitutions in the alpha chains and 2 in the beta chains were recognized.  相似文献   

4.
Globin prepared from hemoglobin of the brown lemur (Lemur fulvus fulvus) was separated into alpha and beta chains by chromatography on a CM 52 column. The S-aminoethylated alpha and beta chains were each digested with trypsin and resulting peptides were isolated. The amino acid sequences of the tryptic peptides were established. The ordering of these peptides in the alpha and beta chains was deduced from the homology of their amino acid sequences with that of human adult hemoglobin. The primary structure of brown lemur hemoglobin thus obtained differs from that of human hemoglobin in 15 amino acids in the alpha chain and 26 in the beta chain.  相似文献   

5.
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   

6.
The adult greater Kudu antelope has two hemoglobin components, Hb A and Hb B, with one alpha and two beta chains. The complete amino-acid sequences of these three chains are presented. The two beta chains differ only in one residue at position 16 (Gly----Ser) and may be the product of two allelic genes. The primary structure of the chains was determined by sequencing the tryptic peptides after their isolation from the tryptic digest of the chains by high performance liquid chromatography. The alignment of these peptides was deduced from homology with the chains of bovine hemoglobin. Between the Kudu hemoglobins and those of cattle a high degree of homology was found.  相似文献   

7.
Globin prepared from hemoglobin of adult tupai (Tupaia glis) was separated into alpha and beta polypeptide chains by CM-cellulose column chromatography. The S-aminoethylated alpha polypeptide chain and S-carboxymethylated beta polypeptide chain were each digested with trypsin, and the sequences of all the peptides thus obtained were established. The ordering of these tryptic peptides in the alpha and beta polypeptide chains was deduced from the homology of their primary structures with that of human adult hemoglobin. In this way the primary structures of the alpha and beta polypeptide chains of tupai hemoglobin were established; 27 amino acids in the alpha polypeptide chain and 26 in the beta chain differ from those in human adult hemoglobin.  相似文献   

8.
Polyacrylamide and starch gel electrophoresis of the hemoglobin of the killifish Fundulus heteroclitus reveal the presence of four clearly distinguishable components. These isohemoglobins, each tetramers consisting of alpha and beta chains, can be preparatively separated by ion exchange chromatography on DEAE-cellulose and are homogeneous according to isoelectric focusing in polyacrylamide gels. Oxygen equilibria of the isolated hemoglobin components (Hb I, Hb II, Hb III, and Hb IV) show only minor differences in the magnitude of the Bohr effect and in the effect of ATP on the binding of oxygen. Four different globin chains, alphaa, alphab, betaa, and betab, can be separated by ion exchange on CM-cellulose. Hb I is a homotetramer of alphab and betab chains, Hb IV consists of alphaa and betaa subunits, and components II and III are heterotetramers consisting of all four chains. The alpha and beta chains differ significantly in amino acid composition. A model suggesting the existence of 10 different isohemoglobins, 6 of which have stable intersubunit contacts, has been proposed to account for the qualitative and quantitative aspects of the electrophoretic behavior of the components. Separations of the isohemoglobins on DEAE-cellulose under slightly modified conditions provide additional support for the model.  相似文献   

9.
The chromatography of the hemoglobin of the rock hyrax (Procavia habessinica) gives two components (73% HbI and 27% HbII). The amino-acid analysis and the sequences of the globin chains elucidated with the phenylthiohydantoin method, did not show any differences between the alpha I and alpha II or beta I and beta II chains, respectively. The different chromatographical behaviour cannot be explained. After chain separation by chromatography on CM-52 cellulose, all four primary structures were elucidated automatically in a sequenator on the chains and the tryptic peptides. In 20% of the beta I chains the N-terminal valine was blocked by acetyl. The alignment was performed by homology with the chains of human adult hemoglobin. The alpha chain of the rock hyrax has 142 amino-acid residues, i.e. one residue more than normal mammalian alpha chains, caused by an insertion of glutamine in the GH region supposed between positions 115 and 116. A comparison of human and hyrax hemoglobins shows an exchange of 21 amino-acid residues in the alpha chains and of 24 in the beta chains. Some substitutions in alpha 1 beta 1 contacts and in the surrounding of the heme are not supposed to effect the function of the hemoglobin. The phylogenetic relationship between the rock hyrax and the Indian elephant (Elephas maximus) on the one hand and with some Perissodactyla on the other, is discussed. Up to now the exchanges of alpha 110(G17)Ala leads to Ser and beta 56(D7)Gly leads to His have only been found in hyrax and elephant. This indicates a certain relationship between Hyracoidea and Proboscidea.  相似文献   

10.
In contrast to most other mammals, the yak, which is native to high altitudes, has two major fetal and two or four major adult hemoglobin (Hb) components. We report the oxygen affinities and sensitivities to pH and 2,3-diphosphoglycerate of the two fetal and two adult Hbs commonly found in calves, compared to those of adult cow Hb A, and relate these findings to their primary structures and to placental maternal-fetal oxygen transfer at altitude. Arranged in order of decreasing oxygen affinity the Hbs are F1 (alpha I2 gamma 2), F2 (alpha II2 gamma 2), A1 (alpha II2 beta II2), and cow Hb A. The higher affinity of the fetal than the adult yak Hbs correlates with the beta 15Trp----Phe substitution, whereas the higher affinity in yak than in cow Hb correlates with the beta 135Ala----Val substitution. The difference in oxygen affinities between yak Hbs A1 and A2, which have identical beta chains, suggests the existence of yet unknown mechanisms determining oxygen affinity. The larger Bohr effects of F2 than F1 and of A2 than A1 are attributable to alpha-chain differences, most probably the alpha I50Glu----alpha II50His substitution.  相似文献   

11.
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   

12.
Two types of embryonic hemoglobins (Hb) containing zeta chains have been identified in the blood of several neonates of Chinese origin with homozygous alpha-thalassemia. In addition to Hb Portland I (zeta 2 gamma 2) which was previously reported, another embryonic hemoglobin has been detected and found to contain zeta chains and beta chains. It is being designated Hb Portland II and has the formula (zeta 2 beta 2). It has a mobility slightly slower than that of Hb A on starch gel electrophoresis at pH 8.6 and has been found in the hemolysates of blood of some but not all hydropic infants. Another component with a mobility faster than that of Hb A2 on starch gel has been isolated from the blood of some hydropic neonates. This latter component is postulated to be zeta 2 delta 2. The occurrence of Hb Portland I and Hb Portland II in these hydropic neonates is consistent with the hypothesis that, in the absence of normal alpha chain production, zeta chains are continued to be produced at later states of development than normal and form tetramers with each of the beta-like globin chains. Because Hb Portland II has not been found in blood from all hydropic neonates, we postulate that the presence of this hemoglobin in these fetuses may be correlated with the gestational age of the fetus at the time of birth.  相似文献   

13.
The complete primary structure of the two major hemoglobin components of sperm whale (Physeter catodon) is presented. The major components A and B account for 55% and 40% respectively whereas the minor component constitutes for 5% of the total hemoglobin. The globin chains were separated on CM-Cellulose in 8M urea buffer. The sequence was determined by automatic Edman degradation of tryptic and hydrolytic peptides in a liquid phase sequencer. Alignment of the sequence with human hemoglobin shows 22 exchanges each for the alpha I and alpha II and 21 exchanges for the beta I and beta II chains. Within the two beta-chains three differences have been located, beta NA2 His/Gln, beta A2 Gly/Ala and beta A8 Leu/Val. The two alpha-chains are characterized by heterogeneities at position alpha A8 Val/Ile or Ala/Ile (ratio of the phenylthiohydantoin derivatives of the amino acids 1:1) and alpha AB1 Asn/Ser (ratio of the phenylthiohydantoin derivatives of the amino acids 6:4). The role of these exchanges in modulating oxygen affinity is discussed.  相似文献   

14.
The complete amino-acid sequences of the alpha and beta chains of adult hemoglobin of harbor seal, Phoca vitulina that belong to carnivora were determined as follows. The alpha and beta chains isolated by chromatography on a CM-cellulose column were digested with trypsin after S-carboxymethylation. Amino-acid sequences of the tryptic peptides derived from both chains were analysed. Comparing the primary structures of the alpha and beta chains of the seal hemoglobin with those of human, dog, bear, badger and cat, 19, 12, 12, 11, and 16 substitutions, respectively, were recognized in the alpha chain, and 12, 10, 4, 6, and 19 (22) in the beta chain.  相似文献   

15.
The erythrocytes of the adult Cormorant contain two hemoglobin components in a ratio of 83% Hb A to 17% Hb D. The primary structures of the alpha A-, alpha D- and beta-chains are presented. The globin chains were separated by high-performance liquid chromatography and cleaved enzymatically and/or chemically. The native chains and their fragments were sequenced using liquid- or gas-phase sequencers, and the peptides aligned using the homology to human and to avian hemoglobin sequences. Compared to human hemoglobin, there are 46 amino-acid replacements in the alpha A-chains (67.4% homology), 65 replacements in the alpha D-chains (53.9% homology) and 45 replacements in the beta-chains (69.2% homology). In the functionally important regions, the percentage of amino-acid substitutions, as compared to human hemoglobin, is 13.2% in the alpha A-, 19.0% in the alpha D - and 16.0% in the beta-chains. The importance of the replacement beta 135 arginine (other birds)----glycine (Cormorant) in the phosphate-binding pocket and its effect on phosphate binding will be discussed.  相似文献   

16.
The kinetics of CO association to and dissociation from the two isomers of monoliganded species alpha ICO beta I(alpha II beta II) and alpha I beta I (alpha II beta COII) has been studied by double-mixing stopped-flow and microperoxidase methods. The monoliganded species were generated by hybridization between excess ferric Hb and alpha CO2 beta +2 or alpha +2 beta CO2 prepared by high-pressure liquid chromatography (HPLC). The results indicated that: 1) there were no significant differences in the reactivities of alpha and beta chains in the first step of ligation; 2) in the second step of ligation there was significant cooperativity in the reaction of deoxyhemoglobin with 0.05 or 0.1 equivalent of CO. Diliganded species were therefore formed in significant amounts. The double-mixing HPLC results suggested that in the second step of ligation alpha chains reacted faster than the beta chains, and the main diliganded species formed was alpha I beta ICO (alpha IICO beta II) or its isomer alpha ICO I(alpha II beta IICO). These results seem to indicate that the reaction of the first CO is mostly random and in the second step of ligation CO binds more to the tetramers in which one beta chain is already ligated: alpha I beta I (alpha II beta II) + CO----alpha ICO beta I (alpha II beta II) and alpha I beta ICO (alpha II beta II) + CO----alpha I beta ICO (alpha IICO beta II).  相似文献   

17.
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   

18.
The minor component of the human adult hemoglobin Hb A2 (alpha2/delta2) was isolated. The peptide chains were separated by counter current distribution, the delta-chains digested with trypsin and all hydrolysis splitting products separated and quantitatively characterized. With the film technique the different peptides were sequenced with hydrophilic phenylisothiocyanates I and IV or by the propyne programme. The complete sequence of the delta-chains is given and compared with the sequence reported in former investigations, in which the delta-chain sequence was only partly elucidated. Having completely sequenced the delta-chains of the human hemoglobin, we found the 10 previously reported exchanges and no additional exchanges with respect to the beta-chains.  相似文献   

19.
The alpha and beta chains of White-Throated Capuchin (Cebus capucinus) hemoglobin were separated and digested by trypsin. The tryptic peptides were isolated and sequenced by conventional methods. The peptides in each chain were aligned by the homology of their sequences with those of human adult hemoglobin. The primary structures thus deduced are compared with those of other primate hemoglobins, and we discuss the molecular evolution of hemoglobins, in particular the rate of evolution in New World monkey hemoglobins.  相似文献   

20.
Total hemolysates of Synbranchus marmoratus Bloch, 1795, captured in Vitoriana, district of Botucatu, State of S?o Paulo, Brazil, were submitted to agar-starch gel electrophoresis on glass slides using 42 mM-Tris 1.7 mM EDTA-6.1 mM borate buffer, pH 8.8, for the gel and 10 mM borate-1.7 mM NaOH buffer, pH 8.6, for the cuvette. Three distinct hemoglobin bands were detected, with Hb I being of the cathodic type. Cellulose acetate electrophoresis in 800 mM Tris-2.1 mM EDTA buffer, pH 8.9, containing 6 M urea and 2.25 mM beta-mercaptoethanol indicated the presence of four globin chains denoted alpha 1, alpha 2, beta and gamma. It is suggested that the probable tetrameric constitution of the hemoglobin of Synbranchus marmoratus Bloch, 1795 is Hb I (alpha (2)2 gamma 2), Hb II (alpha (1)2 gamma 2) and Hb III (alpha (1)2 beta 2).  相似文献   

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