Effect of NH2-terminal acetylation on the oxygenation properties of vertebrate haemoglobin

Chandrasekhar Natarajan; Anthony V. Signore; Vikas Kumar; Roy E. Weber; Angela Fago; Jay F. Storz

doi:10.1042/BCJ20200623

Effect of NH₂-terminal acetylation on the oxygenation properties of vertebrate haemoglobin

Chandrasekhar Natarajan^*, Anthony V. Signore, Vikas Kumar, Roy E. Weber, Angela Fago, Jay F. Storz

^*Corresponding author af dette arbejde

Institut for Biologi - Zoofysiologi

Publikation: Bidrag til tidsskrift/Konferencebidrag i tidsskrift /Bidrag til avis › Tidsskriftartikel › Forskning › peer review

5 Citationer (Scopus)

Abstract

In vertebrate haemoglobin (Hb), the NH2-terminal residues of the α- and β-chain subunits are thought to play an important role in the allosteric binding of protons (Bohr effect), CO2 (as carbamino derivatives), chloride ions, and organic phosphates. Accordingly, acetylation of the α- and/or β-chain NH2-termini may have significant effects on the oxygenation properties of Hb. Here we investigate the effect of NH2-terminal acetylation by using a newly developed expression plasmid system that enables us to compare recombinantly expressed Hbs that are structurally identical except for the presence or absence of NH2-terminal acetyl groups. Experiments with native and recombinant Hbs of representative vertebrates reveal that NH2-terminal acetylation does not impair the Bohr effect, nor does it significantly diminish responsiveness to allosteric cofactors, such as chloride ions or organic phosphates. These results suggest that observed variation in the oxygenation properties of vertebrate Hbs is principally explained by amino acid divergence in the constituent globin chains rather than post-translational modifications of the globin chain NH2-termini.

Originalsprog	Engelsk
Tidsskrift	The Biochemical journal
Vol/bind	477
Nummer	19
Sider (fra-til)	3839-3850
Antal sider	12
ISSN	0264-6021
DOI	https://doi.org/10.1042/BCJ20200623
Status	Udgivet - okt. 2020

Adgang til dokumentet

10.1042/BCJ20200623

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http://www.scopus.com/inward/record.url?scp=85092945248&partnerID=8YFLogxK

Citationsformater

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title = "Effect of NH2-terminal acetylation on the oxygenation properties of vertebrate haemoglobin",

abstract = "In vertebrate haemoglobin (Hb), the NH2-terminal residues of the α- and β-chain subunits are thought to play an important role in the allosteric binding of protons (Bohr effect), CO2 (as carbamino derivatives), chloride ions, and organic phosphates. Accordingly, acetylation of the α- and/or β-chain NH2-termini may have significant effects on the oxygenation properties of Hb. Here we investigate the effect of NH2-terminal acetylation by using a newly developed expression plasmid system that enables us to compare recombinantly expressed Hbs that are structurally identical except for the presence or absence of NH2-terminal acetyl groups. Experiments with native and recombinant Hbs of representative vertebrates reveal that NH2-terminal acetylation does not impair the Bohr effect, nor does it significantly diminish responsiveness to allosteric cofactors, such as chloride ions or organic phosphates. These results suggest that observed variation in the oxygenation properties of vertebrate Hbs is principally explained by amino acid divergence in the constituent globin chains rather than post-translational modifications of the globin chain NH2-termini.",

keywords = "amino-terminal acetylation, Bohr effect, oxygen binding, post-translational modification, recombinant hemoglobin",

author = "Chandrasekhar Natarajan and Signore, {Anthony V.} and Vikas Kumar and Weber, {Roy E.} and Angela Fago and Storz, {Jay F.}",

year = "2020",

month = oct,

doi = "10.1042/BCJ20200623",

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TY - JOUR

T1 - Effect of NH2-terminal acetylation on the oxygenation properties of vertebrate haemoglobin

AU - Natarajan, Chandrasekhar

AU - Signore, Anthony V.

AU - Kumar, Vikas

AU - Weber, Roy E.

AU - Fago, Angela

AU - Storz, Jay F.

PY - 2020/10

Y1 - 2020/10

N2 - In vertebrate haemoglobin (Hb), the NH2-terminal residues of the α- and β-chain subunits are thought to play an important role in the allosteric binding of protons (Bohr effect), CO2 (as carbamino derivatives), chloride ions, and organic phosphates. Accordingly, acetylation of the α- and/or β-chain NH2-termini may have significant effects on the oxygenation properties of Hb. Here we investigate the effect of NH2-terminal acetylation by using a newly developed expression plasmid system that enables us to compare recombinantly expressed Hbs that are structurally identical except for the presence or absence of NH2-terminal acetyl groups. Experiments with native and recombinant Hbs of representative vertebrates reveal that NH2-terminal acetylation does not impair the Bohr effect, nor does it significantly diminish responsiveness to allosteric cofactors, such as chloride ions or organic phosphates. These results suggest that observed variation in the oxygenation properties of vertebrate Hbs is principally explained by amino acid divergence in the constituent globin chains rather than post-translational modifications of the globin chain NH2-termini.

AB - In vertebrate haemoglobin (Hb), the NH2-terminal residues of the α- and β-chain subunits are thought to play an important role in the allosteric binding of protons (Bohr effect), CO2 (as carbamino derivatives), chloride ions, and organic phosphates. Accordingly, acetylation of the α- and/or β-chain NH2-termini may have significant effects on the oxygenation properties of Hb. Here we investigate the effect of NH2-terminal acetylation by using a newly developed expression plasmid system that enables us to compare recombinantly expressed Hbs that are structurally identical except for the presence or absence of NH2-terminal acetyl groups. Experiments with native and recombinant Hbs of representative vertebrates reveal that NH2-terminal acetylation does not impair the Bohr effect, nor does it significantly diminish responsiveness to allosteric cofactors, such as chloride ions or organic phosphates. These results suggest that observed variation in the oxygenation properties of vertebrate Hbs is principally explained by amino acid divergence in the constituent globin chains rather than post-translational modifications of the globin chain NH2-termini.

KW - amino-terminal acetylation

KW - Bohr effect

KW - oxygen binding

KW - post-translational modification

KW - recombinant hemoglobin

UR - http://www.scopus.com/inward/record.url?scp=85092945248&partnerID=8YFLogxK

U2 - 10.1042/BCJ20200623

DO - 10.1042/BCJ20200623

M3 - Journal article

C2 - 32936244

AN - SCOPUS:85092945248

SN - 0264-6021

VL - 477

SP - 3839

EP - 3850

JO - The Biochemical journal

JF - The Biochemical journal

IS - 19