Engineering oxidative stability in human hemoglobin based on the Hb providence (βK82D) mutation and genetic cross-linking.

Autor: Strader MB; Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, U.S.A., Bangle R; Department of Chemistry, Duke University, Durham, NC 27708, U.S.A., Parker Siburt CJ; Department of Chemistry, Duke University, Durham, NC 27708, U.S.A., Varnado CL; BioSciences Department, Rice University, Houston, TX 77281, U.S.A., Soman J; BioSciences Department, Rice University, Houston, TX 77281, U.S.A., Benitez Cardenas AS; BioSciences Department, Rice University, Houston, TX 77281, U.S.A., Samuel PP; BioSciences Department, Rice University, Houston, TX 77281, U.S.A., Singleton EW; BioSciences Department, Rice University, Houston, TX 77281, U.S.A., Crumbliss AL; Department of Chemistry, Duke University, Durham, NC 27708, U.S.A., Olson JS; BioSciences Department, Rice University, Houston, TX 77281, U.S.A., Alayash AI; Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, U.S.A. abdu.alayash@fda.hhs.gov.
Jazyk: angličtina
Zdroj: The Biochemical journal [Biochem J] 2017 Dec 11; Vol. 474 (24), pp. 4171-4192. Date of Electronic Publication: 2017 Dec 11.
DOI: 10.1042/BCJ20170491
Abstrakt: Previous work suggested that hemoglobin (Hb) tetramer formation slows autoxidation and hemin loss and that the naturally occurring mutant, Hb Providence (HbProv; βK82D), is much more resistant to degradation by H 2 O 2 We have examined systematically the effects of genetic cross-linking of Hb tetramers with and without the HbProv mutation on autoxidation, hemin loss, and reactions with H 2 O 2 , using native HbA and various wild-type recombinant Hbs as controls. Genetically cross-linked Hb Presbyterian (βN108K) was also examined as an example of a low oxygen affinity tetramer. Our conclusions are: (a) at low concentrations, all the cross-linked tetramers show smaller rates of autoxidation and hemin loss than HbA, which can dissociate into much less stable dimers and (b) the HbProv βK82D mutation confers more resistance to degradation by H 2 O 2 , by markedly inhibiting oxidation of the β93 cysteine side chain, particularly in cross-linked tetramers and even in the presence of the destabilizing Hb Presbyterian mutation. These results show that cross-linking and the βK82D mutation do enhance the resistance of Hb to oxidative degradation, a critical element in the design of a safe and effective oxygen therapeutic.
(© 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)
Databáze: MEDLINE
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