FabALACTICA (IgdE) is a cysteine protease that digests human IgG1 at one specific site above the hinge with no need for reducing conditions or co-factors.


FabALACTICA is available in three different product formats:

Product Information

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 discovered1. 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.


(1) Spoerry, C. et al., 2016. Novel IgG-Degrading Enzymes of the IgdE Protease Family Link Substrate Specificity to Host Tropism of Streptococcus Species. PloS one, 11(10), p.e0164809.

Key Characteristics

  • High specificity for digestion above the hinge of human IgG1
  • No need for reducing agents of co-factors
  • No risk of overdigestion
  • Generates homogenous Fab fragments from human IgG1


  • Subunit LC/MS analysis
  • Paired glycan analysis
  • Characterization of bi- or multi specific antibodies
  • Affinity screening
  • Studies of higher order structures
  • Studies on antibodies with mutated hinges

Product Formats


FabALACTICA enzyme supplied as lyophilized powder. The enzyme is available in 2000 unit vials for digestion of up to 2 mg human IgG1.

Immobilized FabALACTICA™

FabALACTICA enzyme immobilized on agarose, allowing for human IgG1 digestion without contaminating the final preparation with FabALACTICA enzyme.

FabALACTICA™ Fab kit

FabALACTICA Fab kit is used for easy preparation and purification of Fab fragments from human IgG1. The kit consists of two parts; Immobilized FabALACTICA and affinity spin columns for purification of intact Fab fragments.


Enzyme Reference Tool

We have developed an “Enzyme Reference Tool” that organizes all published papers using our products. With this tool, you can filter by quality attribute, enzyme used, type of antibody molecule, and technology.



FAQ and Support


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Patent and Disclaimer


Aspects of FabALACTICA™ technology are encompassed by pending patent applications in the name of Genovis AB. The trademark FabALACTICA™ is the property of Genovis AB.

For research use only. Not intended for any animal or human therapeutic or diagnostic use.