Answer
The enzyme was Taq, the DNA polymerase from that bacterium. Taq is useful since its structure is stable, and its activity is not damaged, by near-boiling conditions used in PCR to denature DNA. Other enzymes from that bacterium probably have similar heat tolerance, so they could be used when stability in the face of boiling is needed. Other polymerase enzymes would denature and cease to function if exposed to these temperatures.
Work Step by Step
Review the chapter as it discusses PCR and its origins, and see the role of boiling in the life of the bacterium and in the denaturation of DNA. Use your imagination to see that boiling might be useful elsewhere in biotechnology and, thus, so would the other enzymes from this bacterium.