Transcriptional analysis and proteomics of the holomycin gene cluster in overproducer mutants of Streptomyces clavuligerus

► The hlm genes were overexpressed in S. clavuligerus oppA2::aph in relation to the wild type strain. ► RACE analysis showed that four gene sequences are not correct. ► The hlm gene cluster has been introduced in S. coelicolor M1154.