LAUSR

BACKGROUND The Arctic muskox has economic potential as an alternative meat species gaining increased popularity in the region. The objective of the present study is determine the primary structure and pseudoperoxidase activity of muskox myoglobin (Mb) compared with cattle and water buffalo myoglobins. RESULTS The primary structure of muskox Mb was determined through MALDI-TOF MS-based mapping approach by using the sheep Mb as reference sequence. The muskox Mb consists of 153 amino acid residues and shows 100% identity with sheep Mb, while 98.69% and 97.38% identity is found with cattle and water buffalo Mbs, respectively. Muskox Mb has an autoxidation rate (MetMb formation) higher than both cattle and water buffalo Mbs, at pH 7.2 (37 °C). Moreover, its pseudoperoxidase activity is higher than both cattle and water buffalo Mbs at pH 7.4 (physiological pH), while it is slightly lower than cattle Mb and higher than water buffalo at lower pH (5.8), corresponding to the conditions in meat. CONCLUSION The present study reports for the first time the purification of myoglobin from muskoxen, and furthermore a comparative study on autoxidation and pseudoperoxidase activity with respect to cattle and water buffalo Mbs at both physiological and acid pH. Overall, the current research gives novel information for future studies useful to meat industry considering the importance of myoglobin as principal pigment in meat colour stability. This article is protected by copyright. All rights reserved.