For work involving proteins that require disulfide bond formation we recommend our myTXTL Antibody/DS Kit. It is possible that some proteins with just 1 disulfide bond, such as VHH/Nanobodies, may express and show activity in the myTXTL Pro Kit, but generally speaking disulfide bond containing proteins will have the highest yields and best activity in the myTXTL Antibody/DS Kit.