Mikroaerophiles

Mikroaerophiles are microorganisms that require a reduced oxygen concentration for growth, typically between 2% and 10% O2, compared to the atmospheric level of about 21%. They are distinct from obligate aerobes that require high oxygen levels and from facultative anaerobes that can grow in the presence or absence of oxygen. Mikroaerophiles also differ from obligate anaerobes, which cannot tolerate oxygen at all. Their oxygen requirement is often linked to the presence of specific enzymes, such as superoxide dismutase and catalase, which are necessary to detoxify reactive oxygen species that can be damaging at higher oxygen concentrations. However, the levels of these enzymes in mikroaerophiles are insufficient to protect them from the full atmospheric concentration of oxygen.

This specific oxygen requirement means that mikroaerophiles are often found in environments where oxygen levels are naturally lower. Examples include the soil, sediments in aquatic environments, and the gastrointestinal tracts of animals. Some pathogenic bacteria, such as Helicobacter pylori, which is associated with stomach ulcers, are classified as mikroaerophiles. Their ability to thrive in low-oxygen niches is a key factor in their survival and ecological distribution. Culturing mikroaerophilic bacteria in a laboratory setting requires specialized techniques to create the precise oxygen-depleted atmosphere they need. This is often achieved using gas-generating kits or specialized incubators.