Glutathione S-transferase kappa 1 (GSTK1) is an enzyme that in humans is encoded by the GSTK1 gene which is located on chromosome seven. It belongs to the superfamily of enzymes known as glutathione S-transferase (GST), which are mainly known for cellular detoxification. It has been suggested that, similar to GSTA, GSTK1 may play a role in the buffering of acyl-CoA and xenobiotic-CoA and be involved in their binding activities.