Researchers at the J. Craig Venter Institute (JCVI) published results on Thursday 20,May 2010 describing the successful construction of the first self-replicating, synthetic bacterial cell. The synthetic cell is called Mycoplasma mycoides and is the proof of principle that genomes can be designed in the computer, chemically made in the laboratory and transplanted into a recipient cell to produce a new self-replicating cell controlled only by the synthetic genome.
Daniel Gibson and his colleagues at the J. Craig Venter Institute in Rockville, Maryland, synthesized the genome of the bacterium Mycoplasma codes, consisting of about 1.1 million base pairs. Having assembled the genome inside a yeast cell, they transplanted it into a cell from a closely related species, Mycoplasma capricolum. The success clears the way for developing and testing new variants of existing organisms.
“With this approach, we now have the ability to start with a DNA sequence and design organisms exactly like we want,” says Gibson. “We can get down to the very nucleotide level and make any changes we want to a genome.”
Gibson says that his team is now trying to make different types of synthetic cell, using different pairs of bacteria. The group also plans to use the approach to continue work on its project to create a ‘minimal’ cell that contains only the genes necessary for a cell’s most basic survival. “We finally have an assay for determining the functionality of a genome,” says Gibson. “So we want to start whittling away at this genome and try to determine the smallest number of genes needed to sustain life.”
Several companies are already seeking to take advantage of the new field, called synthetic biology, which combines chemistry, computer science, molecular biology, genetics and cell biology to breed industrial life forms that can secrete fuels, vaccines or other commercial and medicinal products. If you like to fix these issues with simple workouts, you can get a rowing machine after reading best rowing machine reviews and start working out at home.
How Scientists Synthesize the Synthetic DNA
To make the synthetic cell, a team of 25 researchers at labs in Rockville, Md., and San Diego, led by bioengineer Daniel Gibson and Mr. Venter, essentially turned computer code into a new life form. They started with a species of bacteria called Mycoplasma capricolum and, by replacing its genome with one they wrote themselves, turned it into a customized variant of a second existing species, called Mycoplasma mycoides, they reported.
To begin, they wrote out the creature’s entire genetic code as a digital computer file, documenting more than one million base pairs of DNA in a biochemical alphabet of adenine, cytosine, guanine and thymine. They edited that file, adding new code, and then sent that electronic data to a DNA sequencing company called Blue Heron Bio in Bothell, Wash., where it was transformed into hundreds of small pieces of chemical DNA, they reported.
To assemble the strips of DNA, the researchers said they took advantage of the natural capacities of yeast and other bacteria to meld genes and chromosomes in order to stitch those short sequences into ever-longer fragments until they had assembled the complete genome, as the entire set of an organism’s genetic instructions is called. They transplanted that master set of genes into an emptied cell, where it converted the cell into a different species.