Draft 4/27

This was also from the talk I recently attended. The results showed that Lanthanides more specifically Lanthanum play a significant role in methanotrophs respiration. It was found that Lanthanum is critical for methanotrophs to help oxidize methane to methanol. It was found that when Lanthanum was available for cells the XoxF gene was upregulated and the MxaF gene was down regulated. Conversely when Lanthanum wasn’t available the XoxF gene was down regulated and the MxaF gene was upregulated. It was shown that bacteria could survive for a limited time in the formaldehyde by fixing the one carbon in the compound. When methanotrophs were grown in a co-culture with non-methanotrophs present methanol was produced. If the methanotrophs were grown in pure culture without non-methanotrophs present no methanol was produced, this shows that there is a connection between the two different organisms and both are needed for methanotrophs to go complete respiration. The conclusions that can be drawn from these results are that methanotrophs do heavily rely on the availability of Lanthanides in the environment. This also shows that Lanthanides may be commonly used when metabolizing one carbon molecules in other organisms that have yet to be studied. Based off of the results it can be concluded that XoxF is a regulatory gene within methanotrophs that help to with the uptake of Lanthanides. In the talk it was suggested that MxaF may have to do with calcium regulation. Additionally both XoxF and MxaF may be used for communication between methanotrophs and non-methanotrophs. Co-cultures are also essential for methanotrophs respiration. It is hypothesized that methanotrophs produce methanol which is then used by the non-methanotrophs. The non-methanotrophs produce a compound that binds to Lanthanum which the methanotrophs then used for respiration and to produce methanol making them co-dependent. The methanotrophs being able to live in formaldehyde suggests that it employs a TCA cycle during respiration. This study may have environmental applications because methanotrophs can be used to reduce methane sinks around the world. A suggested application was using methanotrophs to oxidize methane in sewage facilities and reduce atmospheric release.