The MoBY-ORF collection will be available through Open Biosystems. The Supplementary Methods online lists the strains used in this study, growth media, plasmid pool preparation method, MoBY-ORF clone construction methods and analysis, procedures for sequencing of the MoBY-ORF collection, procedures for functional complementation analysis of essential genes with MoBY-ORF plasmids and preparation of Theonellamide-AMCA.