What Makes Proteins In A Cell? Life Originates From Cells.

To complement our work on the origin oflife, we have launched a new research project, which, of course, has its ownlong-term goal: to create a "universal receptor cell". This receptorcell is capable of accepting any synthetic DNA software that creates life andsets species as we wish. Have you ever thought about what makes proteins in acell? Currently, in our lab, we have very limited types of receptor cells thatcan be used for genome transplantation. To create a universal recipient cell,we are rewriting the genetic code of the mycoplasma cell so that it cantranscribe and translate any DNA software that is transplanted. This researchshould refine and expand our understanding of this important question below.

Scientists explore what makes proteins in acell. There is a more radical approach. We are looking at what we can do tomake our synthetic genome without needing an existing cell as its recipientcell. Our hope is that we will be able to create synthetic cells, and that theprocess of creation will be such that we start with a cell-free system and thengradually add the basic life components to it, eventually constructing acomplete cell. Although this research project is supposedly a historicalprecedent, the research associated with it goes.

It goes back a long way. As early as thebeginning of the DNA revolution in the 1950s, several research groupsindependently demonstrated that the cell was not absolutely necessary to carryout some of the basic movements of life. They found that even after the cellmembrane had ruptured, protein manufacture was still able to proceed.

The scientific community is studying whatmakes proteins in a cell. This possibility was pioneered by Paul CharlesZamecnik, a professor of medicine at Harvard Medical School and a seniorscientist at Massachusetts General Hospital, located near Harvard University.Zamecnik first became interested in the subject sometime in 1938, when, duringan autopsy of a severely obese woman, he was struck by the "large amountof fat and relative paucity of protein" in the tissues. Driven by this"inexplicable astonishment," he decided to try to figure out howprotein is made, and he has spent much of his career since then on thisquestion.

From the very beginning, Chamelecrecognized that in order to understand the intermediate activity of proteinsynthesis, he needed to develop a cell-free system. After several years ofwork, and with the help of his colleague Nancy Bucher, Chamelec eventuallyachieved this goal, which paved the way for many important discoveries. Amonghis many achievements in this field, Chamelec has revealed the need for ATP forprotein synthesis and the discovery that ribosomes are the site of protein assembly.

Many research groups have worked onreconstructing biological processes from separate components. HeinzFraenkel-Conrat and Robley C. Williams were the first to do such experiments,back in 1955, in which they used tobacco mosaic virus, a virus that can becreated in purified RNA and protein coat to create a functional virus. Shortlythereafter, the underlying genetic code was decrypted and numerous messagesfrom DNA software to proteins were translated, in large part as a result of thepioneering research experiments conducted by Marshall Nirenberg and hispostdoctoral researcher J. Heinrich Matthaei in 1961. In their experiments,they prepared a cell extract that made proteins even in the absence of intactliving cells present. By using synthetic RNA and radioactively labeled aminoacids, they found that the combination of three uracil UUUs was able to formthe codon for the amino acid phenylalanine.

Since then, it has become a common practiceto use DNA or RNA to make proteins in the test tube. One consequence of this isthat cell-free protein synthesis has become an important tool for molecularbiologists. Although these methods traditionally required cell extracts, withthe advent of the so-called "protein synthesis using recombinant elements"(PURE) system, we have been able to perform protein synthesis in cell-freesystems. However, with the advent of the so-called "protein synthesisusing recombinant elements" (PURE) system, we have been able to synthesizeproteins in cell-free systems, and with the introduction of translationmachines that can reconstitute E. coli using purified chemical"components" and ribosomes, this has all changed radically.

So what makes proteins in a cell? We arenow trying to create a new cell and life form using a genome that is a mixtureof enzymes, ribosomes and chemicals (including lipids) without the need for apre-existing cell. Within the next few years, the realistic possibilities forcreating a wide variety of cells in a cell-free system, or in a universal receptorcell, based on computer-designed software for life, will become infinitelygreater.

The feat of creating a cell "from theground up" will open up a myriad of extraordinary new possibilities.First, it will allow us to refine our definition of "life" as weexplore the boundary between the living and the inanimate. This work may alsobe influenced by how we define terms such as "machine" and"organism". In addition, the ability to create life withoutpre-existing cells is also very relevant because it increases our freedom todesign new life forms. In addition, it will also help us to explore someancient life forms, as we can both derive the genomes of extinct organisms byderiving them from the genomes of their living descendants, and use syntheticcells to explore the software properties of this ancient species.