Mikroaerofiielen

Mikroaerofiilen is a term used in microbiology to describe microorganisms that require a low concentration of oxygen for growth. Unlike obligate aerobes, which need oxygen and cannot survive without it, or obligate anaerobes, which are poisoned by oxygen, microaerophiles thrive in environments with oxygen levels lower than those typically found in the atmosphere, usually around 2-10%. They cannot grow in the absence of oxygen but are also harmed by high oxygen concentrations.

These organisms possess metabolic pathways that utilize oxygen as a terminal electron acceptor, similar to aerobes. However, they often have enzymes like superoxide dismutase and catalase that are less efficient or are inhibited by high oxygen levels, leading to the accumulation of toxic reactive oxygen species. This sensitivity necessitates their specific growth conditions.

Examples of microaerophiles include certain species of bacteria such as Helicobacter pylori, the causative agent of stomach ulcers, and Campylobacter jejuni, a common cause of foodborne illness. Some algae and fungi also exhibit microaerophilic characteristics. Culturing these organisms in a laboratory setting often requires specialized equipment, such as gas-generating kits or incubation chambers that can precisely control the oxygen concentration. This requirement for reduced oxygen levels is a defining feature of their physiology and ecological niche.