The family thermoproteaceae

Abstract

The family Thermoproteaceae of the order Thermoproteales, class Thermoprotei, is represented by rod-shaped, strictly anaerobic, microaerophilic or facultatively ae305-0074robic, moderate acidophilic to neutrophilic, hyperthermophilic or extremely thermophilic archaea. Cells measure 0.4-0.7 μm thickness and mostly 1-20 μm long. Sometimes they bear terminal globular bodies, showing the golf club-like cell morphology. They are facultative chemolithoautotrophs or obligate chemoorganotrophs that can respire sulfur, oxygen, nitrate, ferric iron, or other toxic metals such as arsenate. They thrive in terrestrial acidic and neutral hot springs and mud pots, as well as coastal, geothermally heated marine water holes. The family is constituted of five genera, Thermoproteus, Caldivirga, Pyrobaculum, Thermocladium, and Vulcanisaeta. They can be differentiated by several phenetic properties, such as growth temperature and pH, cell motility, and DNA G+C content. Their whole genomes of strains have been sequenced indicating their unique genetic features.