EspH is a hypervirulence factor for Mycobacterium marinum and essential for the secretion of the ESX-1 substrates EspE and EspF
Fig 2
Secretion of EsxA by the eccA1 mutant is growth-medium dependent.
Secretion analysis of the WT M. marinum MUSA, the eccCb1 mutant and the knockout strains espG1, espH and eccA1 grown in Sauton’s defined medium. Immunoblot analysis with anti-EsxA confirmed a requirement of EccA1 for a full secretion of EsxA when cells were grown in this medium. Anti-GroEL2 was used as a loading and lysis control for all samples. Anti-PGRS antibodies, staining the ESX-5 dependent substrates PE_PGRS proteins, were used as a supernatant control for all samples. Equivalent OD units were loaded; 0.3 OD for pellet and 0.6 OD for supernatant or supernatant fractions.