O-phospho-L-homoserine + L-cysteine <=> L,L-cystathionine + phosphate
o-phospho-l-homoserine + l-cysteine <=> l,l-cystathionine + phosphate
O-phospho-L-homoserine + L-cysteine <=> L,L-cystathionine + phosphate
o-phospho-l-homoserine + l-cysteine <=> l,l-cystathionine + phosphate