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Rusakov

Banned

Registered: 2012-12-19

Posts: 34

Synthetic biology for improving food yields

Many closed cycle life support system designed for Mars use plants to produce food for astronauts. One problem I forsee is that the amount of biomass required for such a mission would be prohibitively large.

Or would it be?

Here's an article from Science News about synthetic biology and its applications. One particular fact to note is this:

In the April 2012 Applied and Environmental Microbiology, Silver and colleagues reported engineering a bacterium to churn out up to 200 percent of its initial cellular mass as sugar. The work could be used to develop plants that produce more food per harvest.

If we could improve crop yields by a significant amount, then the biomass needed could be reduced greatly.

Any thoughts?

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SWAT Kats fanatic

Void

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Registered: 2011-12-29

Posts: 7,829

Re: Synthetic biology for improving food yields

I am thinking go with the microbe with the sugar.

An inflated plastic bag on the surface partially filled with water could maintain a relatively gentle habitat for the bacteria, since if there is enough thermal inertia, ice phase can be avoided.  (I would think you would cover these balloons with a UV protective plastic tarp draped over them.

Yeast(O2 + Sugar) = Protein & Alcohol.

Alcohol could likely be feedstock for oil and plastics.

Mushrooms(O2 + Oil & Biowaste) = Certain Nutritions humans can use (Mushrooms can grow in a warm damp cave).

So, you would already have a good start.

After that you would only need a relatively small greenhouse to provide the rest of the needed nutrition.

Of course turning yeast into an appealing food might take some work.

I would start like that, and hope that they also engineer some complex plants for great efficiency.

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RobertDyck

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From: Winnipeg, Canada

Registered: 2002-08-20

Posts: 7,936

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Re: Synthetic biology for improving food yields

Interesting. However, I made several presentations about an idea I have. To use in-vitro chloroplasts harvested from leaves of a plant. Chloroplasts would convert CO2 and water into O2 and sugar. Plants polymerize sugar to form complex carbohydrates, which carbohydrate depends on which plant you get them from. Peas are the easiest to get chloroplasts; they make pea starch.

I keep getting biologists say "why not just use bacteria" or "cyanobacteria". I keep pointing out the same problem: sewage. In-vitro chloroplasts just need CO2 from the cabin's regenerable sorbent system, and water filtered with a reverse osmosis filter. Nothing else. Any whole organism will require many more nutrients, basically you would have to process sewage from the toilet to feed the organisms. That means both solid and liquid human waste (shit and piss). Growing an microbe that produces sugar suitable for human consumption, and growing on processed shit and piss? That requires some serious processing! You don't want the shit and piss getting into food. Dealing with the shit and piss is the major obstacle, and makes the system completely unusable on a spacecraft.

Perhaps these guys would be willing to work on my application. As I've said before, extending the viability of in-vitro chloroplasts has several requirements. One is to harvest them in sterile conditions, another is to isolate them from O2. Havesting in a glove box filled with CO2 would do it. And keep the chloroplasts in a transparent plastic bag filled with sterile water. Actively remove O2 and carbonate the water to keep the O2:CO2 ratio way down. But this would extend viability from 20 minutes to hours. We need 6 months. That requires genetically engineering a pea to produce chloroplasts that recycle waste without depending on other organalles in a leaf cell. Since chloroplasts evolved from cyanobacteria, and currently have 85% the genes from cyanobacteria, we can add more genes from cyanobacteria. In fact, instead of just adding steps currently done in other organalles, add the other two recycling pathways found in cyanobacteria but absent in higher plants. This would make our chloroplasts very efficient. It should also cause the pea that makes them grow faster.

I also wanted a variant that would produce sugar instead of starch. Could these guys do that?

Rusakov

Banned

Registered: 2012-12-19

Posts: 34

Re: Synthetic biology for improving food yields

I also wanted a variant that would produce sugar instead of starch. Could these guys do that?

I'm not sure if they could. I don't know them (or their research) personally.

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