Aeropyrum pernix

Taxobox
color = lightgrey
name="Aeropyrum pernix"
regnum = Archaea
phylum = Crenarchaeota
classis = Thermoprotei
ordo = Desulfurococcales
familia = Desulfurococcaceae
genus = "Aeropyrum"
species = "A. pernix"
binomial = "Aeropyrum pernix"
binomial_authority = Sako et al. 1996

Aeropyrum pernix is an extremophile species of Archaea that is part of the phylum Crenarchaeota. It is a heat-requiring species and was isolated from sediments in the sea off the coast of Japan.

Discovery

Aeropyrum pernix was the first strictly aerobic hyperthermophilic archaea to be discovered. It was originally isolated aerobically from heated marine sediments and venting water collected in 1996 from a solfataric vent at Kodakara-jima Island in Kyushu, Japan.cite journal |author=Sako Y, Nomura N, Uchida A, "et al" |title=Aeropyrum pernix gen. nov., sp. nov., a novel aerobic hyperthermophilic archaeon growing at temperatures up to 100 degrees C |journal=Int. J. Syst. Bacteriol. |volume=46 |issue=4 |pages=1070–7 |year=1996 |pmid=8863437 |url=http://ijs.sgmjournals.org/cgi/reprint/46/4/1070.pdf]

Genome structure

It's complete genome was sequenced in 1999 and is 1,669 kilobases in size, with 2,694 possible genes detected. [cite journal |author=Kawarabayasi Y, Hino Y, Horikawa H, "et al" |title=Complete genome sequence of an aerobic hyper-thermophilic crenarchaeon, Aeropyrum pernix K1 |journal=DNA Res. |volume=6 |issue=2 |pages=83–101, 145–52 |year=1999 |pmid=10382966|url=http://dnaresearch.oxfordjournals.org/cgi/reprint/6/2/83.pdf |doi=10.1093/dnares/6.2.83] All the genes in the TCA cycle were found except for that of α-ketoglutarate dehydrogenase. In its place, the genes coding for the two subunits of 2-oxoacid:ferredoxin oxidoreductase were identified.

Properties

The cells of Aeropyrum pernix are spherical in shape and approximately 1 µm in diameter. The envelope surrounding the cells of Aeropyrum is about 25 nm wide. The organisms grows at temperature between 70 and 100ºC (optimum, 90 to 95ºC), at pH 5 to 9 (optimum, pH 7), and at a salinity of 1.8 to 7% (optimum, 3.5% salinity). The growth of the organisms is not detected at 68 or 102ºC. Below 1.5% salinity, cells lyse by low osmotic shock. The cells of the organisms are sensitive to chloramphenicol and insensitive to ampicillin, vancomycin, and cycloserine. It grows well on proteinaceous substances, with a doubling time under these conditions of about 200 minutes.

References