thermococcus peptonophilus thermococcus peptonophilus thermococcus peptonophilus is a fast-growing hyperthermophilic archaeon. it is coccus-shaped, obligately anaerobic and about 0.7–2 μm in diameter. it is a strict anaerobe and grows exclusively on complex substrates, such as peptone, casein, tryptone, and yeast extract. it cannot use carbon dioxide as a source of carbon. although it can grow somewhat in the absence of elemental sulfur, it prefers sulfur. thermococcus peptonophilus scientific classification domain: archaea kingdom: euryarchaeota phylum: euryarchaeota class: thermococci order: thermococcales family: thermococcaceae genus: thermococcus species: t. peptonophilus binomial name thermococcus peptonophilusgonzález et al. 1996