FabALACTICA is a cysteine protease that digests human IgG1 at one specific site above the hinge (KSCDKT / HTCPPC), generating intact Fab and Fc fragments. The name of the enzyme is derived from the pathogen Streptococcus agalactiae, where it was first discovered (Spoerry et al., 2016). The enzyme is active at pH from 6-8 and does not require reducing conditions or co-factors for activity.
FabALACTICA is recombinantly expressed in E. coli, contains a His-tag, and the molecular weight is 70 019 Da.