Ecific lateral acquisition by diverse actinobacteria (Saini et al., 2011). Soliveri et al. (2000) suggested that WhiB and other Wbl proteins might interact with the major antioxidant thiol mycothiol (MSH), which is widespread among, and apparently confined to, actinobacteria (Fahey, 2012). Genomic searches confirmed that the MSH pathway is present in most Actinomycetales, but it is absent from non