Metals in Methanotrophy

Metals play a pivotal role during one-carbon metabolism as they are important catalysts for numerous enzymatic reactions, can be used for electron transfer, enable radical chemistry, and enhance enzymatic substrate affinity. Metals also coordinate the expression of genes that are involved in their own sensing, sequestration, transport, storage, and use to ensure that their accumulation does not become toxic. Metals such as copper (Cu), iron (Fe), lanthanides (Ln), cobalt (Co), zinc (Zn), molybdenum (Mo), and tungsten (W) are particularly important for methanotrophy. This chapter will describe the role in catalysis for each one of these micronutrients along with the structural and mechanistic details of important catalytic centers. Sensing, uptake, and sequestration mechanisms will be highlighted along with changes in metabolism due to metal limitations during environmental and biotechnological processes. The diverse metal-dependent regulatory effects during methanotrophy will also be addressed, and metal-dependent advances in biotechnology and sustainability will be briefly described.