Structural characterization and stability analysis of phosphorylated nitrosohemoglobin

Xiaoqing Ma; Yangying Sun; Daodong Pan; Jinxuan Cao; Yali Dang

doi:10.1016/j.foodchem.2021.131475

Structural characterization and stability analysis of phosphorylated nitrosohemoglobin

Food Chem. 2022 Mar 30;373(Pt B):131475. doi: 10.1016/j.foodchem.2021.131475. Epub 2021 Oct 27.

Authors

Xiaoqing Ma¹, Yangying Sun², Daodong Pan³, Jinxuan Cao¹, Yali Dang¹

Affiliations

¹ State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo 315211, PR China; Key Laboratory of Animal Protein Food Deep Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315800, PR China.
² State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo 315211, PR China; Key Laboratory of Animal Protein Food Deep Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315800, PR China. Electronic address: sunyangying@nbu.edu.cn.
³ State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo 315211, PR China; Key Laboratory of Animal Protein Food Deep Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315800, PR China. Electronic address: daodongpan@163.com.

PMID: 34763930
DOI: 10.1016/j.foodchem.2021.131475

Abstract

Phosphorylation modification by sodium tripolyphosphate (STP) on nitrosohemoglobin (NO-Hb) and its effect on the protein structure and stability were studied. Phosphate groups were found to bridge to NO-Hb via C-O-P bonds through serine and tyrosine residues. Hydrothermal treatment with STP maintained the α-helix stability of NO-Hb, and this change in secondary structure improved the proteins stability. Compared to NO-Hb, phosphorylated NO-Hb (P-NO-Hb) was more stable with respect to light (outdoor light, indoor light, and dark conditions), oxidant (hydrogen peroxide), high temperature, and non-neutral pH. The absorbance of P-NO-Hb was nearly twice those of Hb and NO-Hb (P < 0.05), and the absorbance of P-NO-Hb decreased more slowly over time than those of Hb and NO-Hb. The results confirm that the presence of phosphate groups can increase the stability of Hb through structural changes.

Keywords: C–O–P bond; LC-MS/MS; Phosphorylation modification; Porcine hemoglobin; Stability.

MeSH terms

Hemoglobins*
Protein Structure, Secondary

Substances

Hemoglobins