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Mammals lost the alpha-galactosidase ability to digest legume sugars. Perhaps a mumps-like virus could put this enzyme into livestock saliva



Livestock are responsible for the emission of much methane, a powerful greenhouse gas. Most of this methane is microbially produced from galactose sugars undigested by mammals, due to the lack of a secreted alpha-galactosidase in saliva. Industrial cattle feed may contain alpha-galactosidase, as supplementing with it allows cattle to digest and gain weight from legume sugars and starchs otherwise lost to methane production.

The mumps virus affects parotid salivary glands of humans. Perhaps a genetically engineered mumps viroid could cause alpha-galactosidase secretion in mammalian livestock saliva. Spreading such a viroid might rapidly reduce methane release from livestock and manure, hasten livestock weight gain, and thus ameliorate the climate crisis.

What actions do you propose?

Proposal: Create a virus conveying to livestock salivary glands the ability to excrete alpha-galactosidase, first targeting cattle.

Who will take these actions?

International not-for-profit consortium of academics and engineers.

Where will these actions be taken?

How much will emissions be reduced or sequestered vs. business as usual levels?

According to Schlesinger W. H. _Biogeochemistry_2nd ed._, Academic Press, 1997:373, Enteric Fermentation and Animal Waste are likely to produce 85 and 25 x10^12 g CH4/yr. If two thirds of this could be eliminated, it would reduce methane emissions by about 73 x10^12 grams methane/year. As methane has 86 times the global warming potential (GWP) of carbon dioxide, this might be equivalent to reducing CO2 emissions by 6.3 x10^15 grams CO2/yr.

What are other key benefits?

Affected livestock and mammals would grow more rapidly on diets including legume sugars and starches.

What are the proposal’s costs?

I am not able to project the cost well.

Time line

Such a viroid might be created over a short term, then used to transform livestock within a second short term.

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