Normally, if you want to create something like this, it's an auxotroph. So it shouldn't survive outside of the carbon-sequestering vat.
Or it's all on a plasmid, so once it's out of the vat plasmid won't be maintained.
Or these will be created in "Synells" [0] that can't really replicate.
Though that's a really interesting thought. If we find a technology to do anything about CO2 levels, it seems plausible that we're going to accidentally go too far in the other direction.
[0] http://www.nature.com/nchem/journal/vaop/ncurrent/full/nchem...
Likewise, moving the lumber or finished goods to consumers will also require some energy that might offset the carbon removed.
Also, most farming and stable forests are mostly carbon neutral. This would require continual seeding, harvesting and sequestration of the cellulose. Maybe it will be a good thing though that cellulose+lignins are so hard to breakdown.
We need to drill in the ocean in order to flare more CO2 into the atmosphere or sea levels will drop to catastrophic levels!
http://inhabitat.com/phillip-ross-molds-fast-growing-fungi-i...
But on humans, they aint. Humans & Technology- not even once.
1. This is in vitro work, and even there it is only 5x as efficient. In vivo I'd expect that rate to go down.
2. Metabolism is expensive. This is probably not a very fit pathway. It takes a lot of energy to produce the proteins and ATP necessary to power this cycle and it's product isn't more ATP. It would incur a substantial fitness cost and in the wild it would likely get out grown by wild bacteria that favor Glucose producing photosynthesis.
Not that a new ice age couldn't happen, but carbon fixation is already at a evolutionary local maximum among the six different wild versions, so I don't see why a 7th would be any different.
One of the things that makes Earth special is the formation of carbonate rocks by life taking CO2 out of the atmosphere and falling to the bottom of the oceans; these rocks are then subducted by tectonics and the CO2 spewed out by volcanoes.
As the Earth's core cools, volcanism will diminish, and so the recycling of CO2.
But perhaps Nuclear fusion can fix everything... However I am not a geologist.
You are a bit too late to the party:
Immediate thought: What happens when that bioengineered E. coli or whatever, which you're hoping evolution will make work even more efficiently, leaves your carbon-sequestering vats and starts reproducing in the wild? Eventually you reach a point where we're getting record low CO2 levels. Hello, new Ice Age.
(I am sure there are many reasons this would not happen but it certainly makes for a nice bullshit explanation if I wanted to write a story set in a far-future ice planet.)