Synthesizes glutathione from L-glutamate and L-cysteine via gamma-L-glutamyl-L-cysteine. ATP + L-cysteine + L-glutamate = ADP + gamma-L-glutamyl-L-cysteine + H(+) + phosphate ATP + gamma-L-glutamyl-L-cysteine + glycine = ADP + glutathione + H(+) + phosphate Binds 2 magnesium or manganese ions per subunit. Sulfur metabolism; glutathione biosynthesis; glutathione from L-cysteine and L-glutamate: step 1/2. Sulfur metabolism; glutathione biosynthesis; glutathione from L-cysteine and L-glutamate: step 2/2. Monomer. In the N-terminal section; belongs to the glutamate--cysteine ligase type 1 family. Type 2 subfamily.