While the majority of proteins with available structures are able to fold independently
and mediate interactions only after acquiring their folded state, a subset of the
known protein complexes contains protein chains that are intrinsically disordered
in isolation. The Mutual Folding Induced by Binding (MFIB) database collects and classifies
protein complexes, wherein all constituent protein chains would be unstable / disordered
in isolation but fold into a well-defined 3D complex structure upon binding. This
phenomenon is often termed as cooperative folding and binding or mutual synergistic
folding (MSF). Here we present a major update to the database: we collected and annotated
hundreds of new protein complexes fulfilling the criteria of MSF, leading to an almost
six-fold increase in the size of the database. Many novel features have also been
introduced, such as clustering of the complexes based on structural similarity and
domain types, assigning different evidence levels to each entry and adding the evidence
coverage label that allowed us to include complexes of multi(sub)domain monomers with
partial MSF.
