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1.
The red blood cells of normal adult ducks contain two main hemoglobins. The most abundant type, HbA, comprises approximately 80% of the total, with the remaining 20% being made up of HbD. An attempt was made to determine whether during hemolytic anemia a special alpha globin chain (alpha s) replaces the alpha chain of HbA found in normal animals. This special stress alpha globin, whose existence has been seriously questioned, was originally postulated to explain the sequence discrepancies obtained between alpha chains of normal and anemic chickens and ducks. Using gel electrophoresis, isoelectric focusing, and HPLC peptide mapping techniques no qualitative differences between the alpha A globins of normal and anemic animals were found. The nature of the beta globin chains present in adult ducks has also never been rigorously established. In this work, a variety of techniques, including HPLC, gel electrophoresis, and microcolumn amino acid analysis, were used to examine the beta chains from each hemoglobin. Using these methods, no differences were found between the beta globin chains of the two hemoglobins.  相似文献   

2.
Embryonic differentiation is at present interpreted as the expression of variable gene activity. It is commonly thought that derepression of operator gene groups is the main cause of progress during development. However it is equally possible that gene repression plays a role in the appearance of new phenotypic characteristics. This paper illustrates such a possibility. It is known that in chickens embryonic haemoglobins exist which are replaced by other haemoglobins at about the sixth day of incubation. Analyses of globin chain composition of these haemoglobins by chromatography and urea/starch gel electrophoresis as well as TLC-fingerprinting and amino acid analyses of the individual globin chains showed that the haemoglobin switch was not associated with appearance of new globin chains but rather with disappearance of a number of embryonic chains. Moreover the relative proportion of the various chains changed at that time. From these findings we conclude that new haemoglobins arise from a recombination ('hybridization in vivo') of those globin chains which remain after the repression of a gene coding for embryonic chains.  相似文献   

3.
The complete primary structure of the major hemoglobin component from the adult European lynx (Lynx lynx) is presented. Presence of two hemoglobin components and three chains, βA, βB, and α, identified by gel electrophoresis. The purification of the globin chains achieved by ion-exchange chromatography. The globin chains were digested with trypsin. The peptide generated were purified by reversed-phase HPLC. Sequencing of the native chains up to 42 cycles and of the tryptic peptides were deduced by Edman degradation in liquid- and gasphase sequencer. The primary structure established aligned with those of human Hb-A. The comparison of lynx globin chains with other representatives of the Felidae, lion, tiger, jaguar, leopard, and cat revealed high homology.  相似文献   

4.
Polyacrylamide gel electrophoresis in urea and Triton X-100 of a hemolysate from human fetal red blood cells produces four major protein bands: alpha, beta, and 2 gamma globin chains. We have verified that the latter two are the G gamma and A gamma globin chains which have respectively glycine or alanine at position 136. After incorporation of either [3H] alanine or [3H] glycine into newly synthesized globin each gamma chain was isolated by preparative electrophoresis. The chains were cleaved with cyanogen bromide at methionines 55 and 133, then subjected to automated sequencing, and the residues from each sequencer turn counted. Glycine incorporation was detected for the third turn (position 136) of the G gamma chain and alanine for the A gamma. Substantial metabolic conversion of [3H] glycine to serine and proline was also noted.  相似文献   

5.
A Triton X-100 acid urea gel system that gives a 2.5- to 3-cm separation of the rabbit globin peaks after 2 h of electrophoresis is described. The relative insensitivity of this method to large amounts of added protein allows a rapid analysis of low specific activity rabbit globins in various cell-free systems (rabbit reticulocyte lysate, wheat germ, duck reticulocyte lysate). These conditions give a similar separation for the globins of several other species. A 3.5-h electrophoresis under these conditions separates all the globin chains of human umbilical cord blood and allows the detection of the altered globin synthetic ratio of α-thalassemia-1 in small samples of cord blood.  相似文献   

6.
The polypeptide chains of Xenopus laevis hemoglobin have been analyzed by sodium dodecyl sulfate (SDS) and acid-urea gel electrophoresis. Four components can be distinguished, each having an approximate molecular weight of 13,000 daltons. Messenger RNA coding for the globin chains has been isolated and characterized. In a denaturing acrylamide gel the mRNA has an approximate molecular weight of 250,000 daltons. The complexity of the RNA is consistent with the presence of four different mRNA molecules, each of this molecular weight. When the mRNA is assayed in a wheat germ in vitro translation system, four polypeptides are synthesized corresponding to the four globin subunits. The relative proportion of the four synthesized polypeptides appears to vary according to the developmental stage of the red blood cells used for mRNA isolation. Hybridization of a complementary DNA (cDNA) copy of the globin mRNA to Xenopus laevis DNA in DNA excess indicates that each of the globin genes is present in one to three copies per haploid genome.  相似文献   

7.
We have investigated the effect of different concentrations of Triton X-100 on the resolution of microgram amounts of different hemoglobin subunit polypeptides during electrophoresis in polyacrylamide gels containing acetic acid, urea, and Triton X-100. The results of these studies indicate that adequate concentrations of Triton X-100 facilitate the resolution of polymorphic globin chains and that this type of electrophoretic separation is technically much simpler and more sensitive than currently used methods. Using this method, known and previously undescribed types of α and β chains can be detected. Furthermore, polyacrylamide gel slabs containing a horizontal gradient of Triton X-100 permit the identification of different globin chains present in lysates of erythrocytes or erythrocyte precursors without prior purification of the hemoglobins.  相似文献   

8.
Polyacrylamide gel electrophoresis in urea and Triton X-100 of a hemolysate from human fetal red blood cells produces four major protein bands: α, β, and 2 γ globin chains. We have verified that the latter two are the Gγ and Aγ globin chains which have respectively glycine or alanine at position 136. After incorporation of either [3H] alanine or [3H] glycine into newly synthesized globin each y chain was isolated by preparative electrophoresis. The chains were cleaved with cyanogen bromide at methionines 55 and 133, then subjected to automated sequencing, and the residues from each sequencer turn counted. Glycine incor-poration was detected for the third turn (position 136) of the Gγ chain and alanine for the Aγ. Substantial metabolic conversion of [3H] glycine to serine and proline was also noted.  相似文献   

9.
Polyacrylamide gel electrophoresis in urea and Triton X-100 of a hemolysate from human fetal red blood cells produces four major protein bands: α, β, and 2 γ globin chains. We have verified that the latter two are the Gγ and Aγ globin chains which have respectively glycine or alanine at position 136. After incorporation of either [3H] alanine or [3H] glycine into newly synthesized globin each y chain was isolated by preparative electrophoresis. The chains were cleaved with cyanogen bromide at methionines 55 and 133, then subjected to automated sequencing, and the residues from each sequencer turn counted. Glycine incorporation was detected for the third turn (position 136) of the Gγ chain and alanine for the Aγ Substantial metabolic conversion of [3H] glycine to serine and proline was also noted.  相似文献   

10.
首次应用非连续聚丙烯酰胺凝胶(12%和7.5%)电泳将胚胎、胎儿及成人溶血液中各种正常珠蛋白链分离。其电泳移动顺序为:α、β、Gγ、δ、Aδ、ε和ζ链,δ与Gγ链得到较好的分离。10例β—地中海贫血杂合子血样的δ链光密扫描测定结果为2.62±0.76%。重型β—地中海贫血患者的Gγ与Aγ比1.09~1.27,各类样品的α/非α链含量比约为1。结合网织红细胞体外培育,~3H—亮氨酸标记新合成的珠蛋白链,以放射性荧光自显影技术测定了五例α—地贫患者的珠蛋白链合成速率,其α/β合成比均小于1(0.79~0.89),而正常对照为0.97。在珠蛋白链的研究中,该方法具有简单、灵敏等优点。  相似文献   

11.
12.
One of the 2 main hemoglobins of the sea snake Pelamis platurus, (the Yellow-bellied sea snake) comprising about 70% of the total hemoglobin, was separated by DEAE-Sephadex column chromatography. From results of gel filtration and iron content determination, both intact sea snake hemoglobin, and the isolated major hemoglobin, were concluded to be composed of 4 subunits with a molecular weight of 66,000-67,000 daltons. Separation of the chains of globin of the major hemoglobin by CM 52 column chromatography gave 3 peaks, named, chains a, b, and c. The approximate molecular weights of chains a, b, and c were deduced by SDS gel electrophoresis to be 14,000, 16,000, and 20,000 daltons, respectively. The peptide maps and amino acid compositions of the three chains were distinctly different. N-Terminal and C-terminal amino acid sequence studies reveal that chains a, b, and c represented the alpha-chain, beta-chain, and beta'-chain differing from the normal beta-chain in having a C-terminal sequence of -Arg-Leu-His-Tyr. From the peak areas of the 3 chains obtained by CM 52 column chromatography, and the peak sizes of the 3 bands separated by SDS gel electrophoresis, it was concluded that the sea snake hemoglobin is composed of a hybrid tetramer, alpha2betabeta'.  相似文献   

13.
The complete primary structure of the major hemoglobin component from the adult European lynx (Lynx lynx) is presented. Presence of two hemoglobin components and three chains, A, B, and , identified by gel electrophoresis. The purification of the globin chains achieved by ion-exchange chromatography. The globin chains were digested with trypsin. The peptide generated were purified by reversed-phase HPLC. Sequencing of the native chains up to 42 cycles and of the tryptic peptides were deduced by Edman degradation in liquid- and gasphase sequencer. The primary structure established aligned with those of human Hb-A. The comparison of lynx globin chains with other representatives of the Felidae, lion, tiger, jaguar, leopard, and cat revealed high homology.Deceased on May 27, 1989.  相似文献   

14.
The primary structure of hemoglobin from goldfish (Carassius auratus)   总被引:1,自引:0,他引:1  
The primary structures of the alpha- and beta-chains from goldfish hemoglobin are given. The globin chains were separated by gel filtration after air-oxidation of globin. After chemical and enzymatical cleavage of the chains, the peptides were isolated by gel filtration and ion exchange chromatography on Dowex. The fish-chains have one residue more than the human chains. The alpha-chain is acetylated at the amino-terminal residue and has no cysteine. Compared with the human chains there are 66 amino-acid differences in the alpha- and 72 in the beta-chains. The implication of these differences for the physiology of the hemoglobin molecule of goldfish is discussed.  相似文献   

15.
 从人工贫血的北京鸭网织红细胞中直接提取总RNA,经Oligo(dT)-纤维素柱层析分离获得珠蛋白mRNA,并经蔗糖密度梯度离心首次得到了电泳单一条带的北京鸭球蛋白mRNA。从凝胶电泳以及蔗糖密度梯度离心鉴定其沉降系数为9S。在麦胚无细胞体外翻译体系中测定了它们的蛋白翻译活力。鸭珠蛋白mRNA促进了~3H-亮氨酸参入新生蛋白的活力,达到对照组的10倍。所翻译的蛋白产物在SDS-聚丙烯酰胺凝胶上的电泳行为与天然鸭珠蛋白一致。 经Oligo(dT)-纤维素及蔗糖密度梯度离心提纯的珠蛋白mRNA,在AMV反转录酶及DNA聚合酶的作用下,分别合成了单链及双链cDNA。其双链链长,经凝胶电泳分析,约为500碱基对。  相似文献   

16.
RNA isolated from Chironomus thummi (Diptera) larvae directs the incorporation of amino acid into newly synthesized products in a cell-free translation system prepared from wheat germ. A fraction of the total cell-free product was specifically immunoprecipitable with antibody against total C. thummi hemoglobin. Sodium dodecyl sulfatepolyacrylamide gel electrophoresis of the immunoreactive material revealed the cell-free product to have an apparent molecular mass approximately 3000 daltons greater than secreted C. thummi globin purified from hemolymph. In contrast, analysis of the immunoreactive material by polyacrylamide gel electrophoresis under nondenaturing conditions indicated several chemically distinct globins to be present in the cell-free immunoreactive products. These results provide evidence suggesting the possible existence of a preglobin and the data further provide the initial foundation required for elucidating the regulatory mechanisms that control the developmental stage-specific expression of the globin genes in C. thummi.  相似文献   

17.
Human globin chain separation by isoelectric focusing   总被引:5,自引:0,他引:5  
Human globin chain separation, a key procedure in the study of hemoglobinopathies, is routinely performed by chromatography on carboxymethylcellulose. This method, though relatively easy and highly reliable, is expensive and time consuming. A new procedure, based on isoelectric focusing, is presented which allows the simultaneous separation of globin chains from multiple samples (at least 20 per gel slab). The method is rapid, inexpensive and can be easily carried out in clinical laboratories, and its high sensitivity allows the identification of radioactive bands even with minute amounts of labelled material. A new phenomenon, called the 'Nonidet P-40 effect', which greatly enhances the separation between gamma and beta chains by binding to these two chains and shifting their pI values in opposite directions, is described.  相似文献   

18.
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   

19.
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   

20.
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