yeeO (Escherichia coli K12):   Putative multdrug exporter, MATE family; A transporter able to export peptides and flavins. When overexpressed allows cells deleted for multiple peptidases (pepA, pepB, pepD and pepN) to grow in the presence of dipeptides Ala-Gln or Gly-Tyr which otherwise inhibit growth. Cells overexpressing this protein have decreased intracellular levels of Ala-Gln dipeptide, and in a system that produces the Ala-Gln dipeptide, overproduction of this protein increases its export. When overexpressed increases secretion of FMN and FAD but not riboflavin; intracellular concentrations of FMN and ribofla [...]