1 Introduction -- 2 Occurrence, genes and gene expression -- 3 Structure and function of -GTs -- 4 Autoprocessing and reaction mechanism of -GTs -- 5 -GT in bioclinical -- 6 -GTs: biotechnological and biomedical applications -- 7 Conclusions -- References

Gamma-Glutamyl Transpeptidases (-GTs) are members of the N-terminal nucleophile hydrolase superfamily, enzymes that cleave the -glutamyl amide bond of glutathione to liberate cysteinylglycine. The released -glutamyl group can be transferred to water (hydrolysis) or to amino acids or short peptides (transpeptidation). -GT plays a key role in the gamma glutamyl cycle by regulating the cellular levels of the antioxidant glutathione, hence it is a critical enzyme in maintaining cellular redox homeostasis.-GT is upregulated during inflammation and in several human tumors, and it is involved in many physiological disorders related to oxidative stress, such as Parkinson{u2019}s disease and diabetes. Furthermore, this enzyme is used as a marker of liver disease and cancer. This book coverscurrent knowledge about the structure-function relationship of -GTs andgives information aboutapplications of -GTs in different fields ranging from clinical biochemistry to biotechnology and biomedicine