Re:Engineered photosynthesis demonstrated in animals in vivo...
by clnq on Wednesday December 07, 2022 @04:10PM
(#33900292)
This is very interesting. In a limited but substantial way, transplanting parts of the photosynthetic cell system could help with a lot of cell-centric metabolic deficiencies in people, from T1 diabetes to hypoxia in general. The delivery method seems to be cumbersome. But perhaps in the next decade we'll have CRISPR vectors that can deliver genetic information for organelles in a cell, and that could also help with rejection.
Re:Engineered photosynthesis demonstrated in animals in vivo...
by dekhn on Wednesday December 07, 2022 @06:07PM
(#33901697)
I have in my head, but have not written down, a sci fi story similar to that- "diybio" where some smart grad students clone cephalopod camoflague genes and make a crispr delivery system to give people the ability to grow moving tattoos that glow (go look at a cuttlefish). They go to burning man and give it away- massive night raves with people dancing around, etc.
based on those good results, they go back to the lab and cook up a general purpose "edit your own genome for free!" project and put all the steps to reproduce it in a github repo. But... after half the world has downloaded and started playing, those burning man people start dying of cancer.
Re:Engineered photosynthesis demonstrated in animals in vivo...
by Mistletoe on Wednesday December 07, 2022 @07:48PM
(#33902622)
For others that may be having similar thoughts, I’ve looked into this before and met this roadblock haha. It’s a great thought experiment for just how much energy a human uses and how much area we need for growing food in the world.
> Our body’s demand for glucose is higher than photosynthesis can accommodate. Associate professor Lindsay Turnbull of the University of Oxford determined that if the surface area of an adult woman contained chlorophyll like a leaf, it would produce only 1% of the daily energy requirements for the person to survive. To live by photosynthesis alone, the woman would need a green body with the surface the size of a tennis court.
Re:Engineered photosynthesis demonstrated in animals in vivo...
by russdill on Wednesday December 07, 2022 @11:48PM
(#33904292)
It's also worth noting that biological photosynthesis is very inefficient. A human consumes on average about 150 watts. The earth gets about 1400 watts of sunlight per square meter. It's not completely impossible to one day have bio-engineered solar powered animals.
Re:Engineered photosynthesis demonstrated in animals in vivo...
by Mistletoe on Thursday December 08, 2022 @11:45AM
(#33910003)
Some napkin math (may be wrong).
A man is about two square meters of skin. Assuming they lay down to photosynthesize most efficiently from perpendicular sun rays that would be one square meter, so 1400 watts. You would need an ~11% efficient conversion to meet the needs of a human. Plants currently top out at about 6.4% for highly efficient C4 plants like sugarcane. 11% is the maximum efficiency possible.
>The photosynthetic efficiency is dependent on the wavelength of the light absorbed. Photosynthetically active radiation (400–700 nm) constitutes only 45% of the actual daylight. Therefore the maximum theoretical efficiency of the photosynthesis process is approximately 11%.
Not only would you have to somehow replicate the extreme efficiency of sugarcane on animal skin (an organ with no support structures for photosynthesis), you’d have to double the efficiency.
Re:Engineered photosynthesis demonstrated in animals in vivo...
by sethbannon on Wednesday December 07, 2022 @04:00PM
(#33900159)
Worth noting that they were able to treat osteoarthritis in mice using transplanted mammalian cells engineered to photosynthesize. They also posit that this can be used to treat common degenerative diseases in humans by enhancing cell anabolism (the process by which cells utilize energy to build molecules and other things like proteins and lipids from smaller molecules). Though still much work to be done there.
Re:Engineered photosynthesis demonstrated in animals in vivo...
by 1letterunixname on Thursday December 08, 2022 @04:37AM
(#33906088)
I think if we had ways to transplant, repair, and/or supplant mitochondria, we might be able to restore function at an organelle level as opposed to MRT one-shot in vitro prior to gestation.
Re:Engineered photosynthesis demonstrated in animals in vivo...
by maxerickson on Thursday December 08, 2022 @07:08AM
(#33907001)
There's a corner case where it is starting to happen. Women with mitochondrial disorders will pass them on to any children they have. Mitochondrial replacement therapy during IVF swaps most of the mitochondria with those from a donor.
Re:Engineered photosynthesis demonstrated in animals in vivo...
by dahfizz on Wednesday December 07, 2022 @04:58PM
(#33900892)
I wonder how it will change the livestock industry. Not having to feed animals alleviates the environmental concerns about eating meat, and would make meat cheaper.
Hell, I would buy myself some photosynthesizing cows and pigs if I can just put them in a pen outside and not have to feed them.
Re:Engineered photosynthesis demonstrated in animals in vivo...
by mytailorisrich on Wednesday December 07, 2022 @06:07PM
(#33901696)
Considering the surface area of a cow and that they apparently ought to eat 14+kg of grass a day plus a few kg of additional feed, a photosynthetic cow would quickly starve to death if you stopped feeding it... (ignoring the still necessary mineral intake)
Re:Engineered photosynthesis demonstrated in animals in vivo...
by jonathankoren on Wednesday December 07, 2022 @06:13PM
(#33901759)
That’s not a fair comparison. This is generating ATP directly, rather extracting sugars and whatnot the plant, most of which is indigestible waste, so it’s not like you’d need the surface area of 14 kg of grass.
The real problem is that you need hemispherical hairless cows. ;)
Re:Engineered photosynthesis demonstrated in animals in vivo...
by akiselev on Wednesday December 07, 2022 @07:08PM
(#33902276)
ATP requires adenine and ribose. The former requires nitrogen fixed for the grass by microorganisms and the latter requires glucose for the pentose phosphate pathway. Adenine might also be recycled by the mitochondria which would further complicate things (can ATP be sent back into the mitochondria? Can the mitochondria recycle adenine without the entire glucose/electron transport pathway?)
I suspect a photosynthetic cow would still need to eat a lot of grass
Re:Engineered photosynthesis demonstrated in animals in vivo...
by akiselev on Wednesday December 07, 2022 @09:02PM
(#33903150)
> You process literal pounds of ADP to ATP and back to ADP, every day.
That's exactly my point. Some percentage of that ADP and ATP will be lost and the adenine/ribose broken down or reused for something else - cells are messy environments. Some of that will be lost permanently to waste. The more turnover in this process, the more opportunity for that loss.
Re:Engineered photosynthesis demonstrated in animals in vivo...
by TeMPOraL on Wednesday December 07, 2022 @06:57PM
(#33902151)
> The real problem is that you need hemispherical hairless cows. ;)
That's a good opportunity to join forces with Sabine Hossenfelder and together move some of excess funding from, say, particle physics, and allocate it to fundamental research on which all physics depends: creation of frictionless, vacuum-rated spherical cows.
Slightly related - this study reminds me of an Andy Weir short story Antihypoxiant - http://www.galactanet.com/oneoff/antihypoxiant.html.
based on those good results, they go back to the lab and cook up a general purpose "edit your own genome for free!" project and put all the steps to reproduce it in a github repo. But... after half the world has downloaded and started playing, those burning man people start dying of cancer.
> Our body’s demand for glucose is higher than photosynthesis can accommodate. Associate professor Lindsay Turnbull of the University of Oxford determined that if the surface area of an adult woman contained chlorophyll like a leaf, it would produce only 1% of the daily energy requirements for the person to survive. To live by photosynthesis alone, the woman would need a green body with the surface the size of a tennis court.
A man is about two square meters of skin. Assuming they lay down to photosynthesize most efficiently from perpendicular sun rays that would be one square meter, so 1400 watts. You would need an ~11% efficient conversion to meet the needs of a human. Plants currently top out at about 6.4% for highly efficient C4 plants like sugarcane. 11% is the maximum efficiency possible.
>The photosynthetic efficiency is dependent on the wavelength of the light absorbed. Photosynthetically active radiation (400–700 nm) constitutes only 45% of the actual daylight. Therefore the maximum theoretical efficiency of the photosynthesis process is approximately 11%.
Not only would you have to somehow replicate the extreme efficiency of sugarcane on animal skin (an organ with no support structures for photosynthesis), you’d have to double the efficiency.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7492815/
Sun-fed beef?
Hell, I would buy myself some photosynthesizing cows and pigs if I can just put them in a pen outside and not have to feed them.
The real problem is that you need hemispherical hairless cows. ;)
I suspect a photosynthetic cow would still need to eat a lot of grass
If you eat fructose, you end up turning some of that into uric acid and excreting it, wastefully. It does other varied harm on its way out.
That's exactly my point. Some percentage of that ADP and ATP will be lost and the adenine/ribose broken down or reused for something else - cells are messy environments. Some of that will be lost permanently to waste. The more turnover in this process, the more opportunity for that loss.
That's a good opportunity to join forces with Sabine Hossenfelder and together move some of excess funding from, say, particle physics, and allocate it to fundamental research on which all physics depends: creation of frictionless, vacuum-rated spherical cows.