What characteristic defines psychrophilic bacteria?

Psychrophilic bacteria are specifically characterized by their ability to thrive in cold environments, typically at temperatures below 15 degrees Celsius (59 degrees Fahrenheit). These microorganisms have adapted to live in extreme conditions, such as polar ice and deep-sea regions, where temperatures are consistently low. This unique adaptation allows psychrophiles to metabolize and reproduce efficiently under such conditions, setting them apart from other bacteria that prefer warmer environments.

Understanding the characteristics of psychrophilic bacteria is critical in fields like food preservation and environmental biology, as their presence can affect microbial dynamics in cold ecosystems and influence the spoilage of refrigerated food products. This knowledge is essential for both industries and various scientific studies regarding climate change's impact on ecosystem temperatures and microbial communities.