Sustainable production of myoglobin meat protein in plant chloroplasts
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Alternative routes for producing animal proteins are crucial for reducing the reliance on traditional livestock farming, which contributes significantly to greenhouse gas emissions, deforestation, and water consumption. Myoglobin (Mb) is an important oxygen-binding hemoprotein found in vertebrate muscle, that enhances the nutritional and sensorial properties of meat. Due to its unique functionality, Mb has been heterologously expressed in a variety of organisms, although only transient expression in Nicotiana benthamiana has been reported for higher plants. In this study, we used chloroplast transformation technology to express porcine Mb in higher plants (tobacco, a non-edible model plant, and lettuce, an edible host) and bovine Mb in the green alga Chlamydomonas reinhardtii. Mb accumulation was estimated by immunoblotting and found to be much higher in tobacco (2.7% total soluble protein (TSP)) and lettuce (1.5% TSP) than Chlamydomonas reinhardtii (<0.25% TSP). The expression in tobacco chloroplasts is also superior to tobacco nuclear expression (using either the cauliflower mosaic virus 35S promoter or Arabidopsis thaliana ubiquitin promoter). Total heme levels were elevated in myoglobin-producing mutants compared to control plants, although porcine Mb purified from tobacco leaves exhibited approximately 35% heme-binding (compared to 80% heme-binding in E. coli-expressed Mb), despite being correctly folded, suggesting that heme availability might be a bottleneck. Overall, our work describes the first report of stable Mb production in higher plants and its effect on photosynthesis and heme levels. This provides a foundation for future plant-made animal proteins for food applications.
Date Issued
2026-06-22
Date Acceptance
2026-06-22
Citation
Frontiers in Plant Science, 2026, 17 (1), pp.1-15
ISSN
1664-462X
Publisher
Frontiers Media S.A.
Start Page
1
End Page
15
Journal / Book Title
Frontiers in Plant Science
Volume
17
Issue
1
Copyright Statement
©2026 Groff, Lu, Feeney, Whitelegge, Shao, Morimoto and Nixon. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
License URL
Identifier
10.3389/fpls.2026.1876707
Subjects
Chlamydomonas
chloroplast
heme
lettuce
myoglobin
tobacco
transplastomic
Publication Status
Published
Date Publish Online
2026-08-06