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Comment by tgtweak | Hacker News Reader

I wonder how efficient it is. If a square meter of the material were to be placed in 1000w/m² sunlight, how many grams of carbon can it scrub per hour? Can the carbon be easily recovered? How many break/repair cycles can this material do without deforming or degrading?

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If this material can convert carbon much more efficiently than plants, it would indeed be a game changer.

Plants are essentially limited by one particularly slow enzyme. There are currently research efforts aimed at fixing that enzyme to make plants much more efficient.

https://www.ncbi.nlm.nih.gov/pubmed/25123951

unlikely imo. rubisco has been studied intensely for decades without making much headway. furthermore, the evolutionary pressure for an improved rubisco is so immense that if it were possible we'd probably see it in nature.

>furthermore, the evolutionary pressure for an improved rubisco is so immense that if it were possible we'd probably see it in nature.

I disagree with this logic, as one could apply it to any theoretical biologic feature. The fact that random-walking evolutionary processes haven't stumbled upon a more optimal solution has nothing to do with whether such a solution exists or is easy to find.

Specifically, the gradient crawl that evolution gives must yield viable organisms among every step. If something is within a local maxima that cannot be climbed out of while remaining viable, then evolution can't do anything by definition. That doesn't mean that a better global maxima doesn't exist, and an organism engineered to a better state.

On the other hand, organisms are generally very "fault tolerant" systems in the small—if you get a crucial gene copied, and then one of the copies mutates to do something weird while the other remains functioning, the resulting organism is probably going to be viable, since the weird thing that the mutated copy of the gene does will [unless it's some very specific type of "weird thing" it's producing] be treated by the body as just another foreign enzyme to xenometabolize or foreign antibody to attack.

And the organism's genetic line can persist with that mutant gene indefinitely, building onto it until it becomes a useful feature.

(This isn't so true in especially small organisms, where an extra gene here and there might blow their size or resource budget. This is one of several things constraining the evolution of mitochondria, for example.)

In such incredibly high-dimensional landscapes, such a thing as "local maxima" basically does not exist (you need a local minimum in every single dimension at once). Not to mention that in this case it's not a continuous fitness landscape - you can make wild jumps in each evolutionary step, so the situation of "maximum that can't be climbed out of under given constraints" is even harder to come by.

Indeed. Sunlight alone can't pull a significant amount of water out of the atmosphere, and plants/bacteria need additional energy in the form of sugars to pull carbon out of CO2 in the air.

Where's all this energy coming from?

>plants/bacteria need additional energy in the form of sugars to pull carbon out of CO2 in the air.

Sorry perhaps this is not what you meant to write. For anyone who wants an unmangled understanding of photosynthesis please consult Wikipedia or other text of your choice.

Yes! I am pretty sure that I got confused ... either getting the Krebs Cycle the wrong way around or confused about where the ATP came from... Possibly the latter, this will teach me to comment about half remembering biology from over 25 years ago whilst still half asleep ..

However my original poorly explained thought stands there needs to be an extra component that will be consumed like ATP or H2O...

There is glucose in the compound, as per the article.

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