The Effect of Copper and Cerium on the Transcriptome of Methylosinus trichosporium OB3b

Using RNA-Seq analysis we compared the transcriptome of Methylosinus trichosporium OB3b grown in the presence of varying amounts of copper and cerium. When copper was added in the absence of cerium, expression of genes encoding for both soluble and particulate methane monooxygenases varied as expected. Genes encoding for copper uptake, storage, and efflux also increased, indicating that methanotrophs must carefully control copper homeostasis. When cerium was added in the absence of copper, expression of genes encoding for alternative methanol dehydrogenases varied as expected, but few other genes were found have differential expression. When cerium concentrations were varied in the presence of copper, few genes were found to be either up or downregulated, indicating that copper over rules any regulation by cerium. When copper was added in the presence of cerium, however, many genes were upregulated, most notably multiple steps of the central methane oxidation pathway, the serine cycle, and the ethylmalonyl-CoA pathway. Many genes were also downregulated, including those encoding for nitrogenase and hydrogenase. Overall design: Examination of transcriptome of Methylosinus trichosporium OB3b when growing at presence or absence of copper and cerium.