Practice question

Hyperthermophiles are extremophiles with optimum growth temperature above eighty degrees Celsius, maximum often exceeding 100, isolated from submarine hydrothermal vents black smokers, terrestrial solfataras, geothermally heated sediments and deep oil reservoirs. Members include archaeal Pyrolobus fumarii 106 degrees, Thermococcus kodakarensis, Thermus, bacterial Thermotoga maritima, Aquifex aeolicus chemolithoautotroph. Adaptations include proteins with increased ionic networks, compact hydrophobic cores, higher charged residue proportion, reduced thermolabile asparagine glutamine, oligomerization enhancing stability; membranes composed of ether linked isoprenoid lipids, tetraether monolayers spanning membrane, saturated fatty acids preventing leakage; DNA stabilized by reverse gyrase introducing positive supercoils preventing strand separation, associated with histone like proteins HTa, high intracellular potassium polyamines. Chaperonins thermosome GroEL stabilize folding. Enzymes Taq polymerase active 75 degrees enables PCR, amylases lipases used industry at high temperature reducing contamination risk. Distinguishing hyperthermophiles from thermophiles 55 to 80 and mesophiles clarifies ecological niches and biotechnology exploiting thermostable biocatalysts for starch processing and biofuel production.