Use of plasma induced modification of biomolecules (PLIMB) to evaluate hemin dissociation from fish and bovine methemoglobins

James Whalin; Yuting Wu; Yifei Wang; Surendranath P Suman; J Leon Shohet; Mark P Richards

doi:10.1016/j.foodchem.2024.139576

Use of plasma induced modification of biomolecules (PLIMB) to evaluate hemin dissociation from fish and bovine methemoglobins

Food Chem. 2024 May 8:452:139576. doi: 10.1016/j.foodchem.2024.139576. Online ahead of print.

Authors

James Whalin¹, Yuting Wu², Yifei Wang³, Surendranath P Suman³, J Leon Shohet², Mark P Richards⁴

Affiliations

¹ University of Wisconsin-Madison, Department of Animal and Dairy Sciences, Meat Science and Animal Biologics Discovery, 1933 Observatory Dr, Madison, WI 53706, United States.
² University of Wisconsin-Madison, Department of Electrical and Computer Engineering, Engineering Hall, 1415 Engineering Dr, Madison, WI 53706, United States.
³ Department of Animal and Food Sciences, University of Kentucky, Lexington, KY 40546, United States.
⁴ University of Wisconsin-Madison, Department of Animal and Dairy Sciences, Meat Science and Animal Biologics Discovery, 1933 Observatory Dr, Madison, WI 53706, United States. Electronic address: mprichards@ansci.wisc.edu.

PMID: 38735109
DOI: 10.1016/j.foodchem.2024.139576

Abstract

Hemin dissociation occurs much faster from fish methemoglobin (metHb) compared to mammalian metHb yet the mechanism remains poorly understood. This may involve enhanced solvent access to His(E7) of fish metHbs by a protonation mechanism. Plasma induced modification of biomolecules (PLIMB) produces free radicals that covalently modify solvent accessible residues of proteins, and so can provide insight regarding accessibility of hydronium ions to protonate His(E7). PLIMB-induced modifications to heme crevice sites of trout IV and bovine metHb were determined using tandem mass spectrometry after generating peptides with Trypsin/Lys-C. αHis(CE3) was more modified in trout attributable to the more dynamic nature of bovine αHis(CE3) from available crystal structures. Although His(E7) was not found to be more modified in trout, aspects of trout peptides containing His(E7) hampered modification determinations. An existing computational structure-based approach was also used to estimate protonation tendencies, suggesting His(E7) of metHbs with low hemin affinity are more protonatable.

Keywords: Distal histidine; Hemoglobin; Lipid oxidation; Muscle foods; Myoglobin; Oxidative pathology; Quality deterioration.