30 June 2007

Bacterial Genome Transplanted, Next Step--Synthetic Organism?

After replacing DNA in mycoplasma capricolum organism with the chromosome from mycoplasma mycoides, scientists at the Ventner Institute are planning work on a completely synthetic organism.
Scientists at the J. Craig Venter Institute (JCVI), a genomics research facility, transplanted a bacterial chromosome from one type of bacteria into another, and have completely replaced an entire bacterial genome and its expression. The work of Carole Lartigue, Ph.D. and colleagues was published in the latest issue of Science:

The JCVI team devised several key steps to enable the genome transplantation. First, an antibiotic selectable marker gene was added to the M. mycoides LC chromosome to allow for selection of living cells containing the transplanted chromosome. Then the team purified the DNA or chromosome from M. mycoides LC so that it was free from proteins (called naked DNA). This M. mycoides LC chromosome was then transplanted into the M. capricolum cells. After several rounds of cell division, the recipient M. capricolum chromosome disappeared having been replaced by the donor M. mycoides LC chromosome, and the M. capricolum cells took on all the phenotypic characteristics of M. mycoides LC cells.

As a test of the success of the genome transplantation, the team used two methods -- 2D gel electrophoresis and protein sequencing, to prove that all the expressed proteins were now the ones coded for by the M. mycoides LC chromosome. Two sets of antibodies that bound specifically to cell surface proteins from each cell were reacted with transplant cells, to demonstrate that the membrane proteins switch to those dictated by the transplanted chromosome not the recipient cell chromosome. The new, transformed organisms show up as bright blue colonies in images of blots probed with M. mycoides LC specific antibody.

The group chose to work with these species of mycoplasmas for several reasons -- the small genomes of these organisms which make them easier to work with, their lack of cell walls, and the team's experience and expertise with mycoplasmas. The mycoplasmas used in the transplantation experiment are also relatively fast growing, allowing the team to ascertain success of the transplantation sooner than with other species of mycoplasmas.

According to Dr. Lartigue, "While we are excited by the results of our research, we are continuing to perfect and refine our techniques and methods as we move to the next phases and prepare to develop a fully synthetic chromosome."

Synthetic biology is one of many approaches to studying the mechanisms of life. Craig Ventner says that he will create an organism that will solve the energy crisis. Perhaps he will. As long as western civilisation survives the onslaughts of anti-enlightenment thinking, I suspect that organisms that can produce unlimited energy will be the least of achievements from synthetic biology, nano-biology, biologic computing etc.

Because western educational systems do not teach students to use their broad intellectual capacities, most humans--even in the developed world--do not have a clue about the multiple revolutions in scientific discovery that are teetering on the very brink of the activation energy hump. Some students of the singularity believe that the true revolution will require the creation of a friendly superhuman machine intelligence.

Personally, I believe that machine augmentation of human intelligence will be enough--once humans learn to use the intellects they possess. But since the educational establishments are incapable of helping humans learn about their intrinsic capacity, there may be some delay.

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