What do bacteria feed on living things?

Bacteria feed on living things by breaking down organic matter, including sugars, proteins, and fats, which they obtain from host organisms or their environment. Some bacteria are decomposers, feeding on dead organic material, while others can be pathogens that derive nutrients from living hosts, often causing disease in the process. Additionally, certain bacteria form symbiotic relationships with living organisms, providing benefits such as nutrient cycling in exchange for sustenance.