TABLE 9.
Examples of thermophilic and hyperthermophilic enzymes with applications as molecular biology reagents
| Enzyme | Origin | Applications | Properties | Source or reference(s) |
|---|---|---|---|---|
| Taq polymerase | T. aquaticus | PCR technologies | Optimal activity at 75°C, pH 9.0 | 26, 199 |
| Vent DNA polymerase | T. litoralis | Optimal activity at 75°C, proofreading activity | 2, 271 | |
| Deep Vent DNA polymerase | P. furiosus | Optimal activity at 75°C, proofreading activity; t1/2, 23 h (95°C) | 2, 343 | |
| C. therm DNA polymerase | Carboxydothermus hydrogenoformans | Reverse transcription-PCR | Reverse transcriptase activity, 3′→5′ proofreading activity; optimal activity as 60–70°C | Roche Molecular Biochemicals |
| DNA polymerase | Thermus thermophilus | Reverse transcriptase activity | Roche Molecular Biochemicals | |
| Pfu DNA ligase | P. furiosus | Ligase chain reaction and DNA ligations | Active at 45–80°C; t1/2 >60 min (95°C) | Stratagene |
| Tcs DNA ligase | Thermus scodoductus | Ligase chain reaction | Optimal activity at 45°C | Roche Molecular Biochemicals |
| DNA binding protein Ssod7 | S. solfataricus | Time-reducing and specificity-enhancing in DNA-DNA hybridizations; locking of antisense oligonucleotide to target sequence | Sequence-aspecific DNA binding; ATP-independent, homology-dependent DNA annealing at 60°C | 123 |
| Serine protease (PreTaq) | Thermus strain Rt41A | DNA and RNA purifications; cellular structures degradation prior to PCR | Optimal activity at 90°C, pH 8.0; t1/2, 20 min (90°C) (+CaCl2) | Life Technologies |
| Protease S | P. furiosus | Protein fragmentation for sequencing | Optimal activity at 85–95°C, pH 6.0–8.0; 80% active after 3 h (95°C) | TaKaRa Biomedicals |
| Methionine aminopeptidase | P. furiosus | Cleavage of the N-terminal Met in proteins | Optimal activity at 85–95°C, pH 7.0–8.0; stable for 1 h (75°C) | TaKaRa Biomedicals |
| Pyroglutamate aminopeptidase | P. furiosus | Cleavage of the N-terminal l-pyroglutamate in proteins | Optimal activity at 95–100°C, pH 6.0–9.0; 95% active after 2.5 h (75°C) | TaKaRa Biomedicals |
| Carboxypeptidase | S. solfataricus | C-terminal sequencing | Broad specificity (can release basic, acidic, and aromatic residues); stable in solvents at 40°C | 66 |
| Alkaline phosphatase | T. neapolitana | Enzyme-labeling applications where high stability is required | Optimal activity at 85°C, pH 9.9; t1/2, 4 h (90°C) (+ Co2+) | 87 |