Alternative primary structures in the transmembrane domain of the chicken erythroid anion transporter

Isolation and characterization of the chicken erythroid anion transporter (band 3) cDNA clone, pCHB3-1, revealed that the chicken erythroid band 3 polypeptide is 844 amino acids in length with a predicted mass of 109,000 daltons. This polypeptide is composed of a hydrophilic N-terminal cytoplasmic domain and a hydrophobic C-terminal transmembrane domain. The approximately 90 N-terminal amino acids of the human and murine erythroid band 3 polypeptides are absent in the predicted sequence of the chicken erythroid band 3 polypeptide. The absence of this very acidic N-terminal region is consistent with the lack of binding of glyceraldehyde-3-phosphate dehydrogenase to chicken erythroid band 3, as well as the relatively basic isoelectric point observed for this molecule. The remainder of the cytoplasmic domain shows little similarity to the cytoplasmic domain of the murine and human erythroid band 3, with the exception of the putative ankyrin-binding site, which is highly conserved. In contrast, the transmembrane domain of the chicken band 3 polypeptide is very similar to that of the murine erythroid and human nonerythroid band 3 polypeptides. The transmembrane domain contains 10 hydrophobic regions that could potentially traverse the membrane 12 to 14 times. In addition, a variant of chicken erythroid band 3, pCHB3-2, was cloned in which one of the hydrophobic regions of pCHB3-1 is lacking. The transcript complementary to pCHB3-2 accumulated in chicken erythroid cells in a similar manner as the transcript complementary to pCHB3-1 during embryonic development. This is the first example of a transporter protein or ion channel with alternative primary structures in its membrane-spanning segments.

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Isolation and characterization of the rainbow trout erythrocyte band-3 protein

European Journal of Biochemistry ◽

10.1111/j.1432-1033.1989.tb14709.x ◽

1989 ◽

Vol 181 (1) ◽

pp. 181-187 ◽

Cited By ~ 9

Author(s):

Frank MICHEL ◽

Victor RUDLOFF

Keyword(s):

Rainbow Trout ◽

Band 3 ◽

Band 3 Protein ◽

Isolation And Characterization ◽

Trout Erythrocyte

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Isolation and Characterization of Mutations in theEscherichia coli Regulatory Protein XapR

Journal of Bacteriology ◽

10.1128/jb.181.14.4397-4403.1999 ◽

1999 ◽

Vol 181 (14) ◽

pp. 4397-4403 ◽

Cited By ~ 22

Author(s):

Casper Jørgensen ◽

Gert Dandanell

Keyword(s):

Amino Acids ◽

Purine Nucleoside Phosphorylase ◽

Mutational Analysis ◽

Regulatory Protein ◽

Three Dimensional ◽

Dimensional Structure ◽

Wild Type ◽

Isolation And Characterization ◽

In The Wild

ABSTRACT In this work, the LysR-type protein XapR has been subjected to a mutational analysis. XapR regulates the expression of xanthosine phosphorylase (XapA), a purine nucleoside phosphorylase inEscherichia coli. In the wild type, full expression of XapA requires both a functional XapR protein and the inducer xanthosine. Here we show that deoxyinosine can also function as an inducer in the wild type, although not to the same extent as xanthosine. We have isolated and characterized in detail the mutants that can be induced by other nucleosides as well as xanthosine. Sequencing of the mutants has revealed that two regions in XapR are important for correct interactions between the inducer and XapR. One region is defined by amino acids 104 and 132, and the other region, containing most of the isolated mutations, is found between amino acids 203 and 210. These regions, when modelled into the three-dimensional structure of CysB from Klebsiella aerogenes, are placed close together and are most probably directly involved in binding the inducer xanthosine.

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ISOLATION AND CHARACTERIZATION OF RIBONUCLEIC ACID FROM RAT LENS

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o62-007 ◽

1962 ◽

Vol 40 (1) ◽

pp. 41-47 ◽

Cited By ~ 1

Author(s):

Anima Devi

Keyword(s):

Amino Acids ◽

The Other ◽

Ocular Lens ◽

E Coli ◽

Isolation And Characterization ◽

Coiled Structure ◽

Calf Thymus ◽

Original Procedure ◽

Polynucleotide Chain

RNA from rat ocular lens has been isolated by a method based on Kirby's original procedure (7), but greatly modified so as to avoid any degradation of RNA by RNase during the process of its extraction from lenses. The absorption at 260 mμ of a 1.0% solution of this purified material in a 1-cm cell is 1.95. Its N/P ratio is 1.58. It has 20 to 25% activity of that of yeast-soluble RNA in accepting activated amino acids. When this RNA (like all other RNA's) is heated and cooled the polynucleotide chain can again form loops, thus suggesting a randomly coiled structure for this RNA. On the other hand, DNA preparations from calf thymus, rat liver, and E. coli showed irreversible changes when heated and cooled.

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Brain and Erythrocyte Anion Transporter Protein, Band 3, as a Marker for Alzheimer’s Disease: Structural Changes Detected by Electron Microscopy, Phosphorylation, and Antibodies

Gerontology ◽

10.1159/000213835 ◽

1997 ◽

Vol 43 (1-2) ◽

pp. 44-66 ◽

Cited By ~ 5

Author(s):

Marguerite M.B. Kay ◽

Joseph Goodman

Keyword(s):

Electron Microscopy ◽

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Structural Changes ◽

Protein Band ◽

Band 3 ◽

Transporter Protein ◽

Anion Transporter

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Isolation and characterization of the chicken cardiac myosin light chain (L-2A) gene. Evidence for two additional N-terminal amino acids.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)89289-4 ◽

1985 ◽

Vol 260 (7) ◽

pp. 4478-4483

Author(s):

B Winter ◽

H Klapthor ◽

K Wiebauer ◽

H Delius ◽

H H Arnold

Keyword(s):

Amino Acids ◽

Light Chain ◽

Myosin Light Chain ◽

Cardiac Myosin ◽

Isolation And Characterization ◽

Terminal Amino

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Amino acid sequence of penicillopepsin. I. Isolation and characterization of the chymotryptic peptides

Canadian Journal of Biochemistry ◽

10.1139/o76-125 ◽

1976 ◽

Vol 54 (10) ◽

pp. 872-884 ◽

Cited By ~ 9

Author(s):

Alexander Kurosky ◽

Theo Hofmann

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Amino Acid Sequence ◽

Amino Acid Sequences ◽

Acid Protease ◽

Terminal Region ◽

Isolation And Characterization

The amino acid sequences of 48 peptides obtained from a chymotryptic digest of the mould acid protease, penicillopepsin (EC 3.4.23.7), have been determined. These peptides established the sequences of 26 unique fragments of up to 28 residues in length. The 28-residue fragment was identified as the N-terminal region. The C-terminal region is represented by a 13-residue fragment. The amino acids contained in these fragments account for some 85% of the residues of the enzyme.

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Biochemical and Mutational Characterization of the Heme Chaperone CcmE Reveals a Heme Binding Site

Journal of Bacteriology ◽

10.1128/jb.185.1.175-183.2003 ◽

2003 ◽

Vol 185 (1) ◽

pp. 175-183 ◽

Cited By ~ 31

Author(s):

Elisabeth Enggist ◽

Michael J. Schneider ◽

Henk Schulz ◽

Linda Thöny-Meyer

Keyword(s):

Amino Acids ◽

Covalent Bond ◽

Resonance Structure ◽

Visible Range ◽

Nuclear Magnetic Resonance Structure ◽

Heme Binding ◽

Alanine Scanning Mutagenesis ◽

Isolation And Characterization ◽

Vinyl Group

ABSTRACT CcmE is a heme chaperone that binds heme transiently in the periplasm of Escherichia coli and delivers it to newly synthesized and exported c-type cytochromes. The chemical nature of the covalent bond between heme and H130 is not known. We have purified soluble histidine-tagged CcmE and present its spectroscopic characteristics in the visible range. Alanine scanning mutagenesis of conserved amino acids revealed that H130 is the only residue found to be strictly required for heme binding and delivery. Mutation of the hydrophobic amino acids F37, F103, L127, and Y134 to alanine affected CcmE more than mutation of charged and polar residues. Our data are in agreement with the recently solved nuclear magnetic resonance structure of apo-CcmE (PDB code 1LIZ) and suggest that heme is bound to a hydrophobic platform at the surface of the protein and then attached to H130 by a covalent bond. Replacement of H130 with cysteine led to the formation of a covalent bond between heme and C130 at a low level. However, the H130C mutant CcmE was not active in cytochrome c maturation. Isolation and characterization of the heme-binding peptides obtained after a tryptic digest of wild-type and H130C CcmE support the hypothesis that heme is bound covalently at a vinyl group.

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Isolation and partial characterization of antibody- and globin-enriched complexes from membranes of dense human erythrocytes

Biochemical Journal ◽

10.1042/bj2780057 ◽

1991 ◽

Vol 278 (1) ◽

pp. 57-62 ◽

Cited By ~ 46

Author(s):

R Kannan ◽

J Yuan ◽

P S Low

Keyword(s):

Membrane Protein ◽

Cell Surface ◽

Integral Membrane Protein ◽

Protein Band ◽

Reticuloendothelial System ◽

Band 3 ◽

Isolation And Characterization ◽

Protein Clusters ◽

Associated Proteins

In previous studies we have described a process whereby an erythrocyte in biochemical distress can initiate its own removal by macrophages of the reticuloendothelial system. This process involves the clustering of the integral membrane protein band 3 by denatured haemoglobin and the subsequent recognition of the exofacial poles of clustered band 3 and associated proteins by autologous antibodies. To determine whether this clearance pathway might mediate normal cell turnover, the fraction of normal erythrocytes containing the 0.5% densest cells, which are known to be destined for immediate removal, was isolated and characterized biochemically. This densest fraction was found to contain 6 times more membrane-bound globin (haemichromes) and 10 times more surface-bound autologous IgG than the other fractions containing cells of lower density. To determine whether the autologous IgG was physically associated with the haemichrome-stabilized membrane protein clusters, a procedure was developed for isolation and characterization of the microscopic aggregates. The isolated aggregates were found to contain a disulphide-cross-linked mixture of several membrane proteins, predominantly haemichromes, spectrin and band 3. Although the aggregates constituted only 0.09% of the total membrane protein, they still contained approximately 55% of the total cell-surface IgG. Since in control studies anti-(blood group A) antibodies, which are distributed randomly over the surface of type A cells, could not be recovered in the aggregate, we conclude that the autologous cell-surface IgGs were physically associated with the membrane protein clusters when they were co-isolated with them in our procedure. Thus the 640-fold enrichment of autologous IgG in the aggregates compared with regions of the membrane devoid of tightly clustered protein suggests that sites of integral protein clustering either are non-specifically sticky to IgG or are viewed as foreign or ‘non-self’ by the immune system and aggressively opsonized with IgG.

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