| Pyrodictium |
| Morphology | Pyrodictium |
| CELLULAR |
| Staining | Gram-negative |
| Morphology | Cells disk- to dish-shaped, highly variable in diameter, ranging from 0.3 to 2.5 um, about 0.2 um thick. Produce fibers, 0.04- 0.08 um thick, which form networks connecting the cells |
| Motility | nonmotile |
| Specialized structures | Cell envelope composed of protein subunits in hexagonal array |
| Division |
| COLONIAL |
| Solid surface |
| Liquid | Vigorous shaking prevents cell growth. |
| Growth Parameters | Pyrodictium |
| PHYSIOLOGICAL |
| Tropism | Chemolithotrophic, thriving by hydrogen-sulfur autotrophy |
| Oxygen | Strictly anaerobic |
| pH | Growth occurs at pH 5-7; optimum pH: around 5.5. |
| Temperature | Optimum temperature:105`C maximum: 110`C; minimum: 82`C. |
| Requirements | Optimal NaCl concentration: around 1.5%; maximum: 12%; minimum: 0.2%. |
| Products | H2S is formed from molecular sulfur and hydrogen |
| Enzymes | |
| Unique features | Isopranoid ether lipids present (T.Langworthy, personal communication). Elongation factor 2 is ADP-ribosyulatedby diphtheria toxin (F. Klink, personal communication) |
| ENVIRONMENTAL |
| Habitat | |
| Lifestyle | |
| Pathogenicity |
| Distribution |
| Genome | Pyrodictium |
| G+C Mol % | 62 |
| Reference | Pyrodictium |
| First citation | Stetter, K.O., H. Konig and E. Stackebrandt. 1983 Pyrodictium gen. nov., a new genus of submarine disc shaped sulfur reducing archaebacteria growing optimally at 105 oC. Syst. Appl. Microbiol. 4: 535-551 |
| The Prokaryotes | |
| Bergey's Systematatic | p 2248 K. O. Stetter |
| Bergey's Determinative | p 753 |
| References |