Type VII secretion systems are bacterial secretion systems first observed in the phyla Actinomycetota and Bacillota. Bacteria use such systems to transport, or secrete, proteins into the environment.[1] The bacterial genus Mycobacterium uses type VII secretion systems (T7SS) to secrete proteins across their cell envelope.[2] The first T7SS system discovered was the ESX-1 System.[2]
T7SS has been studied as a virulence factor associated with the ESX-1 system in Mycobacterium tuberculosis.[2] These secretion systems are often found in gram-positive bacteria. Type VII secretion systems are necessary in Mycobacterium because of their impermeable membrane.[3] The RD1 locus or Gene for Type VII secretion can create a lytic effect through ESX-1 transport.[4]