Artificial Enzymes - The Nanobiotechnology - page 65

synthetic.enzymes.with.minimal.activity.could.be.very.valuable..The.question.is.whether.
evolutionary.pathways.through.sequence.space.exist.connecting.these.relatively.abundant.
poor.catalysts.to.the.extremely.rare.sequence.that.encodes.a.highly.optimized.enzyme.with.
eficiency. approaching. those. of. natural. proteins.. Comparison. of. the. three-dimensional.
structures.of.a.102-residue.helical.bundle.and.the.citrate.synthase.it.functionally.replaced.
(Fisher.et.al..2011).would.suggest.that.a.tremendous.amount.of.evolution.would.be.needed.
to. transform. the. former. into. the. latter.. However,. the. incredible. complexity. developed.
(or. perhaps. accumulated). by. nature. may. not. be. necessary. for. human-deined. tasks..
The. elimination. of. unnecessary. complexity. is. a. central. tenet. of. synthetic. biology. (Endy.
2005),.which.seeks.to.transform.biology.into.an.engineering.discipline..Future.work.will.
determine.whether.subtleties.such.as.protein.motion.are.required.for.eficient.catalysis,.or.
whether.they.represent.evolutionarily.acquired.but.ultimately.unnecessary.baggage.that.
can.be.eliminated.by.de.novo.design.
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