What term describes organisms that thrive in acidic environments with a pH of less than 7?

The term that describes organisms thriving in acidic environments with a pH of less than 7 is acidophiles. Acidophiles have adapted to live and grow optimally in conditions where the pH is below 7, making them uniquely suited for such environments. These organisms can be found in various acidic habitats, such as acid mine drainage, acidic hot springs, and certain food products like vinegar.

Understanding acidophiles is essential in microbiology because they play important roles in biogeochemical cycles and can contribute to the fermentation processes in food production. They possess specific adaptations, such as protein structures that remain stable under acidic conditions, and mechanisms to maintain internal pH, which allow them to survive and reproduce despite the unfavorable external environment.