Why doesn't life produce diamond, graphene, nanotubes, etc? Could it?

Question

It seems that life is really good at assembling carbon into extremely complicated molecules (e.g. DNA). Graphene is stronger than any materials currently used by biology. Diamond is harder than any biological materials. Do we know about some inherent difficulty that prevents this? Is there any reason to think that humans will never be able to genetically engineer say, bacteria/fungi/ourselves, to produce diamond, graphene, carbon nanotubes, etc?I'm looking for specific metabolic hurdles that would make this difficult or impossible. (For example, enzymes/proteins can't do that for this reason, or ATP metabolisms don't have enough energy to form the needed bond.)

Answer 1

Those things require energy input that isn't necessary for life. It will not develop on it's own. The other thing is that, even though we know the process for how these things are made, those pre-requisites may not be present in a cell. Raw carbon in a cell will be very quickly expunged or reacted away by other processes used to support the cell. It's not technically impossible, I suppose, but the idea is too far beyond our reach currently to be considered right now.