TIGR president Claire M. Fraser, senior author of this paper, says that eventually a set of rules might be devised concerning lateral gene transfer, perhaps involving engulfment of one cell by another. For now, though, the picture is becoming more complicated as evidence accumulates. "It's much easier to imagine all this going on when you're talking about single-cell organisms," she comments.
The paper announced the sequencing of the bacterium Thermotoga maritima, a hyperthermophile that was originally isolated from geothermally heated marine sediment. Comparing its genome to all 16 other then-sequenced microorganisms, the researchers found that almost one-quarter of its genes were most similar to those of archaeal species. Moreover, 81 of the 451 Archaea-like genes were clustered in regions that often contained a gene order conserved between Archaea and T. maritima, suggesting that large regions of DNA were acquired through lateral transfer. But the most compelling evidence came from phylogenetic ...
