Friday, August 19, 2005
Smaller is Better
Oregon State researchers have been studying SAR11 for about 15 years, and have found this single-celled organism to be a truly elegant example of natural efficiency, so much so that it comprises one of the largest biomasses on Earth and plays a significant role in life and carbon cycles.
SAR11's genome only has 1.3 million base pairs, the smallest number ever found in a free-living organism (not a parasite)*. The press release talks about how humans' genomes are so wasteful, with all that 'junk' DNA, and they may be right; I've just never been comfortable with the term. We keep discovering that some bits of this stuff serves a purpose, why shouldn't the rest of it?
*Compare that to humans' ~3 billion base pairs, Amoeba proteus' ~290 billion, or even Arabidopsis thaliana's ~115 million.
SAR11's genome only has 1.3 million base pairs, the smallest number ever found in a free-living organism (not a parasite)*. The press release talks about how humans' genomes are so wasteful, with all that 'junk' DNA, and they may be right; I've just never been comfortable with the term. We keep discovering that some bits of this stuff serves a purpose, why shouldn't the rest of it?
*Compare that to humans' ~3 billion base pairs, Amoeba proteus' ~290 billion, or even Arabidopsis thaliana's ~115 million.
