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1.
Samples of homozygous bovine serum transferrins have been prepared and their purity has been ascertained by immunological techniques and electrophoretic analysis in SDS. Measurements of carbohydrate composition show that no significant differences exist among the phenotypic variants AA, D1D1, D2D2, and EE. Chromatography of transferrin AA on DEAE-cellulose separated four subfractions, each of which corresponded well with one band obtained by polyacrylamide gel electrophoresis. Carbohydrate analyses of the individual subfractions did not show significant differences in sialic acid, hexose, or hexosamine contents. After desialylation with neuraminidase, each subfraction was converted to a major band and a minor band on gel electrophoresis. From the relative band positions of the desialylated transferrins, it was concluded that possession of sialyl residues by bovine transferrin is not the primary cause of electrophoretic multiplicity. Rather, sialic acid masks an underlying heterogeneity which most likely resides within the polypeptide chain. Further characterization of this heterogeneity will best be undertaken with the isolated asialotransferrin subfractions.This research was supported by Grants MT-4074 and MA-5554 from the Medical Research Council of Canada and a Senior Fellowship (to M. W. C. H.) from the Ontario Heart Foundation.  相似文献   

2.
A new, partially deficient transferrin variant in the pig   总被引:1,自引:0,他引:1  
A new, partially deficient transferrin variant (TF F) was found in serum samples of a wild boar and his offspring from crossing with Pietrain sows. Family analyses confirmed its genetic control by a codominant allele, TFF. Finding of this new variant has brought the total number of pig transferrin variants to nine (F, I, A, B, C, X, D', E, D).  相似文献   

3.
Summary 188 blood samples from Batak of Samosir Island (Sumatra, Indonesia) have been studied for electrophoretic variants of haemoglobin, 14 red cell enzyme and 5 serum protein systems. The acid phosphatase, 6 PGD, PGM1 and ADA enzyme systems are polymorphic, and a single AK 2-1 person was detected. Polymorphism is present in the haptoglobin, transferrin and protease inhibitor systems. Two variant alleles, Tf Dchi and Tf B are present in the transferrin system, but the B variant has not been identified. Similarly, 3 persons with caeruloplasmin variants were found, but also these variants have not been identified. No abnormal haemoglobins were detected. All other systems revealed the presence of only normal phenotypes.
Zusammenfassung 188 Blutproben des Batak-Stammes von Samosir Island (Sumatra, Indonesien) wurden auf elektrophoretische Varianten des Hämoglobins in 14 Erythrocyten-enzym-und 5 Serumprotein-Systemen untersucht. Die Saure Phosphatase, 6GPD, PGM1 und ADA-Systeme sind polymorph, und eine einzige AK 2-1-Person wurde gefunden. In den Haptoglobin-, Transferrin- und Pi-Systemen treten Polymorphismen auf. Zwei abweichende Allele, Tf Dchi und Tf B, sind im Transferrin-System zu finden, aber die B-Variante ist nicht bestimmt worden. Ebenso wurden 3 Personen mit Ceruloplasmin-Varianten gefunden, doch auch diese Varianten wurden nicht identifiziert. Keine abnormen Hämoglobine wurden gefunden. Alle anderen Systeme wiesen nur normale Phenotypen auf.
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4.
Human seminal transferrin (HSmT) is an iron-containing glycoprotein whose structural properties have not been adequately investigated. The carbohydrate content of the purified glycoprotein amount to 6.1%, and monosaccharide analysis revealed the major oligosaccharide moiety to be of the N-glycoside type. The carbohydrate chains were released from the iron-free form by digestion with peptide N-glycosidase F (PNGase F) in the presence of detergents such as SDS and-octylglucoside. After ethanol precipitation and fractionation on Bio-Gel P-6 and Bio-Gel P-2, the oligosaccharide was further purified on Mono-Q and desalted on Bio-Gel P-2. By 600-MHz1H-NMR spectroscopy, the primary structure of the major N-linked oligosaccharide component was established to be: Abbreviations used HSmT human seminal transferrin - HSrT human serum transferrin - PNGase F peptide-N4-(N-acetyl--glucosaminyl)asparagine amidase-F (E.C. 3.5.1.52), commonly known as peptide N-glycosidase F - SDS-PAGE sodium dodecyl sulphate-polyacrylamide gel electrophoresis - GLC gas-liquid chromatography - FPLC fast liquid protein chromatography - EDTA ethylenediaminetetraacetic acid, disodium salt - PMFS phenylmethylsulfonyl fluoride - GlcNAc N-acetylglucosamine - NeuAc N-acetylneuraminic acid - Man, Gal galactose - Fuc fucose  相似文献   

5.
Complete mRNA sequence of transferrin from Galleria mellonella was obtained, and compared with those of other species. Until now, two types of insect transferrin were reported. Transferrins in cockroach and termite have two iron binding sites while those in most other insect groups, studied for the protein, have only one. It was suggested that the presence of two types of transferrin was related with transferrin evolution, because vertebrate transferrins have two iron binding sites, called N and C terminal lobe. It was shown that G. mellonella transferrin also has only one iron binding site (N terminal lobe), and the deduced amino acid sequence was most similar to those of Manduca sexta and Bombyx mori.  相似文献   

6.
Although a large number of human serum transferrin (TF) variants have been described, only one RFLP (AvaI) has so far been found. Here we report three new RFLPs (MvaI in intron 5 and exon 7, BbvI in exon 7) and correlations between RFLPs and between RFLPs and serum TF types. There were strong, but not always complete, disequilibria between RFLP and serum protein alleles. Thus, the most common serum TF variant, C1, was heterogeneous and could be subdivided into two common haplotypes, whereas the C2, C3, and DCHI variants were completely or almost completely (C2) homogeneous. There was a total genotypic agreement between the BbvI polymorphism and the presence/absence of the TF C3 variant, and the mutation that creates the BbvI site was found to lead to a G258S amino acid substitution. Received: 15 June 1997 / Accepted: 15 November 1997  相似文献   

7.
Summary An electrophoretic survey of transferrin variants in 87 species of teleostean fishes showed much individual variation. The majority of the species were polymorphic at the transferrin gene locus, Tf. The clustered distribution of allelomorphs indicated some evolutionary continuity within certain taxonomic families, but this continuity was unexpectedly less apparent within genera.  相似文献   

8.
In an attempt to perform a further investigation on the proposal that an increasing susceptibility to Candida infection in liver injury may be related to unsaturated transferin level (UIBC) and/or to a total amount of transferrin represented by TIBC, we conducted experimental candidiasis using mice with galactosamine-induced liver injury and investigated the effect of preadministration of transferrin prior to inoculation of Candida albicans. Final mortality was 10% in the mice without liver injury and without transferrin (Group 1) and ones with liver injury and with transferrin (Group 3). By contrast a 50% mortality was given in ones only with liver injury (Group 2). The TIBCs in Groups 1 and 3 were significantly higher than that in Group 2. The UIBCs in Groups 2 and 3, although there was no significant difference between them, were significantly lower than that in Group 1. This study confirmed that transferrin (TIBC) may have a direct deterring effect on systemic Candida infection and the decreased TIBC in the liver injury enhances the growth of C. albicans.  相似文献   

9.
A partially deficient and atypical equine transferrin variant, TF N   总被引:1,自引:0,他引:1  
A new, partially deficient and phenotypically atypical transferrin variant, TF N, was detected in sera of a number of Finnhorses belonging to one family. The variant was inherited codominantly. In polyacrylamide gel electrophoresis (pH9.0) of sera, variant N appeared as a single weak band migrating slightly faster than the main anodal band of variant M. After immunoblotting or isolation an additional, still weaker, faster band was observed as well as some trace bands. The cathodal component, which is present in other transferrin variants, could not be convincingly proved. The main component of variant N contained four sialic acid residues.  相似文献   

10.
The present paper reports the distribution of serum protein markers viz. haptoglobin and transferrin in two major groups of Aligarh city of North India. In present study we have undertaken a survey of 538 individuals belonging to eight different populations, four from the Hindu community i.e. Brahmin, Bania, Rajput and Jatav, and the rest four among the Muslim community i.e. Syed, Sheikh, Pathan and Ansari. The heterozygosity ranged from 0.2939 (Ansari) to 0.4873 (Brahmin) for haptoglobin and from 0.000 (Rajput) to 0.1498 (Pathan) for transferrin. The values of D ST are 0.4122 and 0.4406, and that of G ST are 0.5059 and 0.9726 for haptoglobin and transferrin markers respectively. Through F ST test, it has been concluded that there is a high genetic differentiation of populations within Hindu and Muslim groups, though there is absence of any significant differences between these groups.  相似文献   

11.
Six serum protein systems, Gc globulin (Gc), transferrin (Tf), alpha1-antitrypsin (Pi), plasminogen (PLG), alpha2-HS-glycoprotein (AHS), and coaglulation factor XIII B (F13B) have been studied in two Czech populations from Prague (n=243) and Olomouc (n=205). The results are discussed with reference to other investigations in Middle Europe.  相似文献   

12.
Summary A new synthetic medium (referred to as GC3) that supports the growth of the Chinese hamster ovary cell line has been developed. It is composed of a 1∶1 mixture of Ham's F12 and modified Eagle's minimum essential (MEM.S) mediums supplemented with transferrin (10 μg/ml), insulin (80 mU/ml), and selenium (1×10−7 M). Other more simple supplementations of our basal medium MEM.S/F12 (transferrin+insulin, transferrin+selenium, ferrous iron+selenium) also give good cell growth responses. Fibronectin or serum pretreatment is not needed for cellular attachment and spreading. Our culture system is characterized by a continuous serum-free cultivation (more than 200 doublings), a clonal growth, a high density proliferation, and a rapid growth rate near that of cells in serum-supplemented medium.  相似文献   

13.
Ford MJ 《Molecular ecology》2000,9(7):843-855
This paper describes DNA sequence variation within and among four populations of chinook salmon (Oncorhynchus tshawytscha) at the transferrin, somatolactin and p53 genes. Patterns of variation among salmon species at the transferrin gene have been hypothesized to be shaped by positive natural selection for new alleles because the rate of nonsynonymous substitution is significantly greater than the rate of synonymous substitution. The twin goals of this study were to determine if the history of selection among salmon species at the transferrin gene is also reflected in patterns of intraspecific variation in chinook salmon, and to look for evidence of local adaptation at the transferrin gene by comparing patterns of nonsynonymous and synonymous variation among chinook salmon populations. The analyses presented here show that unlike patterns of variation between species, there is no evidence of greater differentiation among chinook salmon populations at nonsynonymous compared to synonymous sites. There is also no evidence of a reduction of within-species variation due to the hitchhiking effect at the transferrin gene, although in some populations nonsynonymous and synonymous derived mutations are both at higher frequencies than expected under a simple neutral model. Population size weighted selection coefficients (4Ns) that are consistent with both the inter and intraspecific data range from approximately 10 to approximately 235, and imply that between 1 and 40% of new nonsynonymous mutations at the transferrin gene have been beneficial.  相似文献   

14.
Glycopeptides are isolated from subtilisin and pronase digests of whole bovine serum transferrin A and D2. The two variants yield glycopeptides with identical ami-no acid composition. Hence, there is probably no amino acid substitution in this region of the peptide chain. Amino acid sequence determination of one glycopeptide (subtilisin glycopeptide 8) gives the sequence: (CHO)Asn-Ser-Ser-Leu-Cys. This sequence is identical with that of residues 491–495 of the sequence for human serum transferrin (MacGillivray et al., 1982) except that in the bovine transferrin, Asp is replaced by Asn, enabling carbohydrate attachment. A second glycopeptide sequence Arg-(CHO)Asn-Ala-Thr-Tyr is observed, and the significance discussed in relation to carbohydrate moieties of serum glycoproteins.  相似文献   

15.
Onconase (ONC) as a novel anti-tumor drug has a significant killing effect on a variety of tumor cells. Drug delivery system mediated by transferrin (TF) and TF receptor (TfR), which can significantly increase the amount of drug uptake in the tumor cells, enhance the initiative target efficiency of drugs and reduce its toxic side effects. It has been widely used in drug delivery and clinical trials. In this study, the rONC-TFn was expressed in Escherichia coli by linking ONC with the N-terminal domain of TF (TFn). ELISA and competitive binding analysis demonstrated that rONC-TFn can bind to TfR. The rONC-TFn protein showed much higher cytotoxicity to the cultured HepG2 and Hela cells than rONC. These results suggested that the N-terminal domain protein of TF promoted the tumor targeting of ONC, and thus the rONC-TFn fusion protein may be further developed as a potential targeted anti-tumor drug.  相似文献   

16.
In starch gel electrophoresis of horse sera each transferrin variant is formed by a strong anodal band and a weaker cathodal band. An 'atypical' variant, Tf C, has two zones of about equal intensity. Family data show that Tf C is genetically controlled by an allele Tf C at the Tf locus. Frequencies of transferrin alleles in various horse breeds are also presented.
After isolation and fractionation of individual transferrin variants (Tf O, Tf D, Tf C) on DEAE-Sephad Summary ex, additional weak bands were detected. The two main zones of each variant were isolated in a pure state and treated with neuraminidase. In all three variants studied the electrophoretic mobility of the slower band (2a) was decreased in two steps, and the faster band (4b) in four steps. The mobilities of bands derived from the fast zone (4b) were slower than mobilities of corresponding bands derived from the slow zone (2a). These results suggest the presence of two sialic acid residues in the slow zone, and of four residues in the fast zone. Residual heterogeneity was independent of sialic acid.  相似文献   

17.
The effects of endotoxin or testosterone on the amount of transferrin 59Fe (or like protein) in the murine macrophages was investigated. The mouse peritoneal macrophages were laden with 59Fe tagged red cells following the injection of mice with either agent. After harvesting the cells, they were lysed and the transferrin iron was released with 40% trichloroacetic acid. The supernatant (extract transferrin iron) and the pellet (other iron proteins iron) were separated by centrifugation and their radioactivities counted. The results were expressed in percentage. The endotoxin group had a geometric mean of transferrin 59Fe of 0.14% compared to 0.28% for the control, p < 0.001. The geometric mean for transferrin 59Fe of the testosterone treated group was 0.51% compared to 0.35% for the control, p < 0.05. Therefore, the endotoxin seems to contract the transferrin pool whereas testosterone seems to expand it.  相似文献   

18.
Homozygous horse transferrin (Tf O) is highly heterogeneous. In starch gel electro-phoresis it gives at least 9 zones. Two main components (2a and 4b) were purified by rivanol and ammonium sulphate precipitation, DEAE-Sephadex chromatogra-phy and SP-Sephadex chromatography. Molecular weights of 75 200 and 80 500 for components 2a and 4b, respectively, were determined by sedimentation equilibrium ultracentrifugation. Amino acid compositions of the two components were similar, and there were no differences in the N -terminus (glutamic acid followed by glu-tamine) and the C -terminus (valine). Differences were found in carbohydrate composition between components 2a and 4b. Component 2a contained 10 moles of sugar components per mole of protein (4 hexoses, 4 hexosamines and 2 sialic acids), while component 4b contained twice the number of both total carbohydrates and individual sugar components. Carbohydrates were identified as mannose and galac-tose (ratio mannose:galactose = 1.5:l), N -acetylglucosamine and N -acetylneu-raminic acid. At present it is not clear whether the difference between the two components resides solely in the difference of carbohydrate contents. It is proposed that component 2a has one diantennary glycan, while component 4b has two.  相似文献   

19.
Polymorphism of the mitochondrial cyt b gene was examined in 35 individuals of common carp and wild common carp (Cyprinus carpio L.). The fish examined represented two natural populations from Khabarovsk krai (Ac and Am), Volga wild common carp, Don wild common carp, and two common carp breeds, Ropsha (strains BB and MM) common carp and Hungarian common carp. The highest level of nucleotide (π) and haplotype (h) diversity was detected in two strains of Ropsha common carp (MM, π = 0.67%, h = 0.7; and BB, π = 0.21%, h = 0.9) and in one population (Am) of Amur wild common carp (π = 0.26%; h = 0.6). The second population of Amur wild common carp (Ac) and Hungarian common carp were characterized by lower variation estimates (π = 0.035%, h = 0.4; and π = 0.09%, h = 0.7, respectively). Genetic homogeneity was demonstrated for the populations of Volga and Don wild common carp (π = 0, h = 0). In the sample of the cyt b sequences examined, three lineages were identified. Lineages I and II united all haplotypes of the Am Amur wild common carp along with two haplotypes of Ropsha common carp, strain MM. The third lineage (III) was formed by the haplotypes of three individuals of Ropsha common carp strain MM, all representatives of Ropsha common carp strain BB, Hungarian common carp, Ac Amur wild common carp, and Don and Volga wild common carps. Statistically significant amino acid differences were observed only for the sequences, corresponding to haplotypes of lineage III, and the sum of sequences of lineages I and II. Effectiveness of different types of markers to differentiate the two subspecies of European and Amur wild common carp (C. c. carpio and C. c. haematopterus) is discussed, as well as the issues of the origin and dispersal of Russian common carp and wild common carp breeds.  相似文献   

20.
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