Complement, contact activation, coagulation, and fibrinolysis are serum protein cascades that need strict regulation to maintain human health. Serum glycoprotein, a C1 inhibitor (C1-INH), is a key regulator (inhibitor) of serine proteases of all the above-mentioned pathways. Recently, an autotransporter protein, virulence-associated gene 8 (Vag8), produced by the whooping cough pathogen, Bordetella pertussis , was shown to bind to C1-INH and interfere with its function. Here you can see a graphical representation of the structure of the Vag8-C1-INH complex determined using cryo-electron microscopy at a 3.6-Å resolution. The structure shows a unique mechanism of C1-INH inhibition not employed by other pathogens, where Vag8 sequesters the reactive center loop of C1-INH, preventing its interaction with the target proteases (PDB code: 7AKV)
#molecularart ... #immolecular ... #pertussis ... #complement ... #activation ... #complex... #CryoEM ... Rendered with @proteinimaging and finished with @corelphotopaint
#molecularart ... #immolecular ... #pertussis ... #complement ... #activation ... #complex... #CryoEM ... Rendered with @proteinimaging and finished with @corelphotopaint
