acidophile

An acidophile is an organism that thrives in acidic environments, with optimal growth occurring between pH 1 and pH 5. These organisms are a type of extremophile, meaning they are adapted to extreme environmental conditions. While the term "acidophile" can also refer to a substance that stains readily with acid stains, in biology, it specifically denotes organisms preferring acidic conditions.123

Many acidophiles are prokaryotic, belonging to the domains of archaea and bacteria. For example, species of Picrophilus are among the most acid-tolerant organisms known, capable of growing at around pH 0. The study of acidophiles contributes to our understanding of the limits of life on Earth and may offer insights into the origins of life and the potential for extraterrestrial life.145