In an important step towards creating synthetic life forms, genetics pioneer George Church has produced a man-made version of the part of the cell that turns out proteins, which carry out the business of life. “If you going to make synthetic life that is anything like current life … you have got to have this … biological machine,” Church told reporters in a telephone briefing. And it can have important industrial uses, especially for manufacturing drugs and proteins not found in nature [Reuters].
Church’s team built a functional ribosome from scratch, molecule by molecule. Ribosomes are molecular machines that read strands of RNA and translate the genetic code into proteins. They are exquisitely complex, and previous attempts to reconstitute a ribosome from its constituent parts – dozens of proteins along with several molecules of RNA – yielded poorly functional ribosomes, and even then succeeded only when researchers resorted to “strange conditions” that did not recapitulate the environment of a living cell, Church said [Nature blog]. Next, the researchers want to produce man-made ribosomes that can replicate themselves.
Church’s work hasn’t yet been published in a peer-reviewed journal; instead he presented his preliminary results at a seminar of Harvard alumni over the weekend. He described how his research team first disassembled ribosomes from E. coli, a common lab bacterium, into its component molecules. They then used enzymes to put the various RNA and protein components back together. When put together in a test tube, these components spontaneously formed into functional ribosomes…. The researchers used the artificial ribosome to successfully produce the luciferase enzyme, a firefly protein that generates the bug’s glow [Technology Review].