The complete genome sequence of <it>Staphylothermus marinus </it>reveals differences in sulfur metabolism among heterotrophic Crenarchaeota

• Main Authors: Barry Kerrie, Lucas Susan, Lapidus Alla, Land Miriam, Sun Hui, Mavromatis Kostas, Elkins James G, Ulrich Luke E, Porat Iris, Hooper Sean, Rodriguez Jason, Dharmarajan Lakshmi, Anderson Iain J, Huber Harald, Zhulin Igor B, Whitman William B, Mukhopadhyay Biswarup, Woese Carl, Bristow James, Kyrpides Nikos
• Format: Article
• Language: English
• Published: BMC 2009-04-01
• Series: BMC Genomics
• Online Access: http://www.biomedcentral.com/1471-2164/10/145

<p>Abstract</p> <p>Background</p> <p><it>Staphylothermus marinus </it>is an anaerobic, sulfur-reducing peptide fermenter of the archaeal phylum Crenarchaeota. It is the third heterotrophic, obligate sulfur reducing crenarchaeote to be sequenced and provides an opportunity for comparative analysis of the three genomes.</p> <p>Results</p> <p>The 1.57 Mbp genome of the hyperthermophilic crenarchaeote <it>Staphylothermus marinus </it>has been completely sequenced. The main energy generating pathways likely involve 2-oxoacid:ferredoxin oxidoreductases and ADP-forming acetyl-CoA synthases. <it>S. marinus </it>possesses several enzymes not present in other crenarchaeotes including a sodium ion-translocating decarboxylase likely to be involved in amino acid degradation. <it>S. marinus </it>lacks sulfur-reducing enzymes present in the other two sulfur-reducing crenarchaeotes that have been sequenced – <it>Thermofilum pendens </it>and <it>Hyperthermus butylicus</it>. Instead it has three operons similar to the <it>mbh </it>and <it>mbx </it>operons of <it>Pyrococcus furiosus</it>, which may play a role in sulfur reduction and/or hydrogen production. The two marine organisms, <it>S. marinus </it>and <it>H. butylicus</it>, possess more sodium-dependent transporters than <it>T. pendens </it>and use symporters for potassium uptake while <it>T. pendens </it>uses an ATP-dependent potassium transporter. <it>T. pendens </it>has adapted to a nutrient-rich environment while <it>H. butylicus </it>is adapted to a nutrient-poor environment, and <it>S. marinus </it>lies between these two extremes.</p> <p>Conclusion</p> <p>The three heterotrophic sulfur-reducing crenarchaeotes have adapted to their habitats, terrestrial vs. marine, via their transporter content, and they have also adapted to environments with differing levels of nutrients. Despite the fact that they all use sulfur as an electron acceptor, they are likely to have different pathways for sulfur reduction.</p>