second forkhead associated (FHA) domain found in Mycobacterium tuberculosis ABC transporter ATP-binding/permease protein Rv1747 and similar proteins
Rv1747 is a putative ATP-binding cassette (ABC) transporter involved in the translocation of an unknown substrate across the membrane. It is required for normal virulent infection by M. tuberculosis. Rv1747 has a cytoplasmic regulatory module consisting of two pThr-interacting forkhead-associated (FHA) domains connected by a conformationally disordered linker with two phospho-acceptor threonines (pThr). Recruitment and phosphorylation of Rv1747 depend on the interaction between its two non-redundant FHA domains and the autophosphorylated form of serine/threonine protein kinase PknF. This model corresponds to the second FHA domain, which has a circularly permuted FHA domain fold with a conserved pThr-binding interface.
Feature 1:putative phosphopeptide binding site [polypeptide binding site]
Evidence:
Comment:based on structures of other FHA domains with bound phosphopeptide
Comment:GR at the C terminus of strand beta3, SRxH just preceding beta5, and motif SxNG in the beta6-beta7 turn indicate a canonical mode of pThr recognition.
Comment:Conserved residues are involved in binding directly to the ligand backbone and phosphate group. Non-conserved residues may determine binding specificity.