PDBsum entry 1bab

Oxygen transport

PDB id

1bab

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Contents

			Protein chains

					143 a.a. *


					146 a.a. *

			Ligands

					HEM ×4


					SO4 ×2

			Waters ×266

* Residue conservation analysis

PDB id:

1bab

Links

Name:

Oxygen transport

Title:

Hemoglobin thionville: an alpha-chain variant with a substitution of a glutamate for valine at na-1 and having an acetylated methionine nh2 terminus

Structure:

Hemoglobin thionville (deoxy) (alpha chain). Chain: a, c. Engineered: yes. Hemoglobin thionville (deoxy) (beta chain). Chain: b, d. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Organism_taxid: 9606

Biol. unit:

Tetramer (from PQS)

Resolution:

1.50Å

R-factor:

0.157

Authors:

J.S.Kavanaugh,A.Arnone

Key ref:

C.Vasseur et al. (1992). Hemoglobin Thionville. An alpha-chain variant with a substitution of a glutamate for valine at NA-1 and having an acetylated methionine NH2 terminus. J Biol Chem, 267, 12682-12691. PubMed id: 1618774

Date:

06-May-92

Release date:

31-Jan-94

PROCHECK

	Headers

	References

Protein chains

P69905 (HBA_HUMAN) - Hemoglobin subunit alpha from Homo sapiens

Seq: Struc:					142 a.a. 142 a.a.*

Protein chains

P68871 (HBB_HUMAN) - Hemoglobin subunit beta from Homo sapiens

Seq: Struc:					147 a.a. 146 a.a.

Key:

Secondary structure

CATH domain

* PDB and UniProt seqs differ at 1 residue position (black cross)

	J Biol Chem 267:12682-12691 (1992)
PubMed id: 1618774

Hemoglobin Thionville. An alpha-chain variant with a substitution of a glutamate for valine at NA-1 and having an acetylated methionine NH2 terminus.
C.Vasseur, Y.Blouquit, J.Kister, D.Promé, J.S.Kavanaugh, P.H.Rogers, C.Guillemin, A.Arnone, F.Galacteros, C.Poyart.

ABSTRACT

In hemoglobin (Hb) Thionville, the substitution of a glutamic acid for the alpha-chain NH2-terminal valine inhibits the cleavage of the initiator methionine which is then acetylated. The elongation of the alpha-chain NH2 terminus modifies the three-dimensional structure of hemoglobin at a region that is known to have an important role in the allosteric regulation of oxygen binding. Relative to Hb A, Hb Thionville has a lower affinity for oxygen, and the heterotropic allosteric effects of protons, chloride, and bezafibrate are reduced. In contrast, the response to 2,3-diphosphoglycerate is normal. Analysis of oxygen equilibrium data within the framework of the two-state allosteric model indicates that the structure of deoxy Hb Thionville is stabilized relative to that of deoxy Hb A. The x-ray crystal structure of deoxy Hb Thionville shows that the glutamate side chain extends away from the alpha 1-alpha 2 interface, whereas the methionine side chain (which has two conformations) extends into the alpha 1-alpha 2 interface, physically displacing chloride and bezafibrate. The increased stability of deoxy Hb Thionville is due to new intrasubunit and intersubunit contacts made by the methionine. These interactions replace the indirect contacts, made through bound chloride ions, that Val-1 alpha normally contributes to the alpha 1-alpha 2 interface.

Literature references that cite this PDB file's key reference

PubMed id

Reference

16618920

J.M.Turner, J.Graziano, G.Spraggon, and P.G.Schultz (2006).
Structural plasticity of an aminoacyl-tRNA synthetase active site.

Proc Natl Acad Sci U S A, 103, 6483-6488.

PDB codes:

1zh0 2ag6

11838022

D.K.Rai, B.Landin, W.J.Griffiths, G.Alvelius, and B.N.Green (2002).
Characterization of the elusive disulfide bridge forming human Hb variant: Hb Ta-Li beta83 (EF7)Gly --> Cys by electrospray mass spectrometry.

J Am Soc Mass Spectrom, 13, 187-191.

11891810

P.Lacan, G.Souillet, M.Aubry, D.Promé, S.Richelme-David, J.Kister, H.Wajcman, and A.Francina (2002).
New alpha 2 globin chain variant with low oxygen affinity affecting the N-terminal residue and leading to N-acetylation [Hb Lyon-Bron alpha 1(NA1)Val --> Ac-Ala].

Am J Hematol, 69, 214-218.

The most recent references are shown first. Citation data come partly from CiteXplore and partly from an automated harvesting procedure. Note that this is likely to be only a partial list as not all journals are covered by either method. However, we are continually building up the citation data so more and more references will be included with time. Where a reference describes a PDB structure, the PDB codes are shown on the right.