“The γ‐… acceptor glycylglycine , a co‐substrate for γ‐GT, … the growth‐inhibitory effect of GSH , which in contrast was decreased by the γ‐GT inhibitors, serine‐borate complex and acivicin, suggesting that … production of reactive forms of oxygen (probably H2O2) was mediated by cysteinyl‐glycine after GSH hydrolysis.”