Methanotrophs have sensitive requirements for growth and often require specific nutrients as well as coculture species in order to thrive in vitro and in vivo. This can provide difficulties when culturing in the lab and when new colonies are seeded into the environment. Metal molecules are of special interest to methanotrophs because they are used in the active site Methane Monooxygenase (MMO) to digest methane. The most important metal to recruit for this is Copper which is incorporated into the particulate form of MMO but iron can also be incorporated into the soluble form of MMO in circumstances in which copper is not readily available. Copper as a consequence of its importance in the function of pMMO also serves as a powerful regulator of transcription and expression for a number of different protein pathways that lead to methanotroph proliferation. Methanotrophs are able to extract copper from their environment from insoluble minerals and weathering of copper rich minerals can serve as an indication of the presence of Methanotroph species.
Testing at the site of soil sampling for the presence of certain nutrients especially copper can reveal how active the growth of methanotrophs may be and as to whether they may be metabolically limited to their soluble form for carbon metabolism. When growing in the lab and eventually in the process of seeding natural environments with methanotrophs these limitations need to be accounted for as a limiting factor in growth.
CH4 Microbial Solutions 