Lincomycin A, originally isolated from Streptomyces lincolnensis, has been widely used for treating Gram-positive bacteria infections in the clinic due to well penetration capability into tissues and cell membrane.As putative transporter genes in lincomycin biosynthetic gene cluster from S.lincolnensis, ImrA and ImrC encode ABC transporter ATP-binding domain and MFS transporter, respectively.To investigate their function, we separately inactivated ImrA and ImrC in a lincomycin high-yielding strain LC-G by homologous recombination.