<P> A microaerophile is a microorganism that requires oxygen to survive, but requires environments containing lower levels of oxygen than are present in the atmosphere (i.e. <21% O; typically 2--10% O). Many microaerophiles are also capnophiles, requiring an elevated concentration of carbon dioxide (e.g. 10% CO in the case of Campylobacter species). </P> <P> Microaerophiles can be cultivated in candle jars . Candle jars are containers into which a lit candle is introduced before sealing the container's airtight lid . The candle's flame burns until extinguished by oxygen deprivation, creating a carbon dioxide - rich, oxygen - poor atmosphere . Other methods of creating a microaerobic environment include using a gas - generating pack and gas exchange . </P> <Ul> <Li> Campylobacter species are microaerophilic . </Li> <Li> Helicobacter pylori, a species of proteobacteria that has been linked to peptic ulcers and some types of gastritis . </Li> </Ul>

Microaerophiles are microbes that grow best at lower