A team of researchers from the
P. torridus - which prefers temperatures of around 60°C and a pH of 0.7 - is one of the most thermoacidophilic organisms known, making it an ideal model for studying the requirements for life in hostile environments. Analysis of the organism's 1.55-megabase genome revealed a number of genes that may play a role in this ability, including 170 ORFs -- 12 percent of the organism's total genes - that play a role in transport and are assumed to be required for detoxification of the cell.
In addition, 92 percent of the P. torridus genome sequence is coding, "which represents the highest coding density in the genomes of the thermoacidophile group," the authors wrote. "Although the consequences for cell physiology and DNA integrity are not yet understood, we believe that the combination of two extremophilic conditions, low pH and high temperature, may have led to the small size and one of the highest coding densities for the genome of P. torridus," they concluded.
In addition, it appears from the researchers' analysis that certain genes considered particularly supportive for the organism's extreme lifestyle are the result of horizontal gene transfer from crenarchaea and bacteria.