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Plants that make muscle amino-acids?

  1. Jun 20, 2009 #1
    Could plants be bio-engineered so that a large fraction of their seed mass was in the form of muscle amino-acids? Do soybeans have a large fraction of their mass in the form of amino-acids that make up muscle protein? I would like such a plant so I could stop eating animal meat and reduce my negative impact on the Earth. You might say just die and reduce your impact on the Earth. You might say that one does not have to eat meat to get required amino-acids. Shame on me that an animal dies because I like the taste of meat.

    Thank you for your help.
  2. jcsd
  3. Jun 20, 2009 #2


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    What the heck are "muscle amino acids?" All proteins, regardless of whether they're of plant or animal origin, are built from the same group of 22 standard amino acids (the ones coded for by DNA, including 2 not normally found in proteins) and a bunch of nonstandard ones.

    Like it or not, humans evolved to eat a varied diet including meat and life survives by eating other life. Ultimately, every living thing--including you--gets eaten and turned into other living things. Now or later, the environmental impact is identical.
  4. Jun 20, 2009 #3
    10 pounds of (dry) grain for 1 pound (wet) steer muscle, hardly the same impact on the Earth?
  5. Jun 20, 2009 #4


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    What do you think will happen to that cow when it dies, which it will?

    As for environmental impact, animals emit FAR more greenhouse gases than pants do. By eating an animal you're reducing those emissions! Plants, on the other hand, make oxygen which we need, y'know, to live.
  6. Jun 20, 2009 #5
    Eat a mixture of grains and legumes to obtain a good balance of amino acids.

    This will suppy a start in good background information.


    "Corn is an important food staple and animal feed. It is an excellent source of carbohydrates, but since it is low in total protein and the protein is of poor quality, a corn diet must be supplemented with protein-rich foods for satisfactory growth. Two genetic mutants, known as opaque-2 and floury-2, which cause a change to floury endosperm in normal dent corn in which they are found, have been discovered to result in an increase in tryptophan and lysine, two essential amino acids. These amino acids are in short supply in corn protein. The presence of either mutant gene in corn results in what is called high-lysine corn and renders it equivalent to skim milk in the diet of humans. Swine fed this type of corn will gain weight three times as fast as those fed normal corn. Plant breeders everywhere are now transferring these genes to varieties and parent lines of hybrids. The development is said to equal in importance the discovery of hybrid corn."
    Last edited by a moderator: Apr 24, 2017
  7. Jun 20, 2009 #6


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    One needs a balanced diet. A combination of grains can provide the 10 essential amino acids as well as others.

    Amino acids

    Essential amino acids
    http://hyperphysics.phy-astr.gsu.edu/HBASE/Organic/essam.html which references
    arginine (available from sesame seeds/flour)
    9 essential amino acids available in quinoa or soy.

    arginine (required for the young, but not for adults)

    Nutritional quality of the protein in quinoa (Chenopodium quinoa, Willd) seeds.

    Amino Acid Content in Wild Rice (Zizania Aquatica L.) Grain
    http://agron.scijournals.org/cgi/content/abstract/68/1/146 [Broken]

    Amino Acid Composition and Biological Value of Cereal Proteins
    By Radomír Lásztity, Máté Hidvégi, International Association for Cereal Chemistry

    Chemical and Biological Data of Rice Proteins for Nutrition and Feeding
    see Table 1

    Amino acids in rice and wheat - see table 4
    from Amino Acid Composition and Biological Value of Cereal Germs

    Cereal Proteins -- Past, Present, Future

    Consider eating fish or seafood for other important elements such iodine.

    Just to add one of my favorite foods - cashews
    Table 2. Amino-Acid Composition of Cashew Kernel Protein
    Code (Text):
    Amino Acid     Composition
    Glutamic Acid     28.0
    Leucine           11.93
    Iso Leucine        3.86
    Alanine            3.18
    Phenylalanine      4.35
    Tyrosine           3.20
    Arginine          10.30
    Glycine            5.33
    Histidine          1.81
    Lysine             3.32
    Methionine         1.30
    Cystine            1.02
    Threonine          2.78
    Valine             4.53
    Tryptophane        1.37
    Aspartic Acid     10.78
    Proline            3.72
    Serine             5.76
    Food protein sources By Norman Wingate Pirie, Monkombu Sambasivan Swaninathan http://books.google.com/books?id=3kE9AAAAIAAJ&pg=PA94&lpg=PA94
    Last edited by a moderator: May 4, 2017
  8. Jun 20, 2009 #7


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    HUH? Ruminants, like cattle, sheep and goats, are far more efficient than humans at converting the energy in fibrous plants into muscle, including being able to use the parts of plants that are not nutritive for humans, like the stalks. And, humans are far more efficient at digesting the muscles of animals than fibrous plants.

    You can get complete proteins by combining different plants, but a diet with no animal products will still lack an essential B vitamin. While it's true that at least in the US a lot of people overconsume meat, dairy and eggs, a healthy diet doesn't eliminate them completely.
  9. Jun 20, 2009 #8
    So... Where does B12 come from? This is very strange. From what I can gather B12 is originally synthesized in bacteria. Not seaweed, not yeast, not animals.

    What organisms originally synthesis B12?
    Last edited: Jun 21, 2009
  10. Jun 21, 2009 #9


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    Ostensibly it is one of the bacteria in the gut of ruminants that produces B12.

    Only bacteria can synthesize vitamin B12.
    Table from Linus Pauling Inst.
    Code (Text):
    Food              Serving  Vit B12
    Clams (steamed)   3 ounces  84.0
    Mussels (steamed) 3 ounces  20.4
    Crab (steamed)    3 ounces   8.8
    Salmon (baked)    3 ounces*  2.4
    Rockfish (baked)  3 ounces   1.0
    Beef (cooked)     3 ounces   2.1
    Chicken (roasted) 3 ounces   0.3
    Turkey (roasted)  3 ounces   0.3
    Egg (poached)     1 large    0.6
    So clams and mussels have high B12 contents. I would guess that this is from the bacteria they filter from seawater or which grow in them somewhere. Simiarly for crabs.

    Beef (and presumabley sheep and goats) have much higher B12 concentration than poultry.


    MIT biologists solve vitamin puzzle
    Vitamin B12 synthesis by human small intestinal bacteria
    Last edited by a moderator: Apr 24, 2017
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