Mce/MlaD (IPR003399)

Short name: Mce/MlaD

Overlapping homologous superfamilies


Domain relationships



This domain is found in all 24 mce genes associated with the four mammalian cell entry (mce) operons of Mycobacterium tuberculosis and MlaD proteins from other Actinomycetales [PMID: 12052567, PMID: 14500535]. The archetype (mce1A, Rv0169), was isolated as being necessary for colonisation of, and survival within, the macrophage [PMID: 8367727]. The domain is also found in:

  • Chloroplast Ycf22 and related cyanobacterial homologues, the majority of which have an N-terminal transmembrane domain and are putative ABC transporters.
  • Proteobacterial homologues, which include MlaD, PqiB, YrbD, YebT, VpsC and Ttg2C. MlaD is part of the ABC transporter complex MlaFEDB that actively prevents phospholipid accumulation at the cell surface [PMID: 19383799]. MlaFEDB complex is composed of two ATP-binding proteins (MlaF), two transmembrane proteins (MlaE), two cytoplasmic solute-binding proteins (MlaB) and a probable periplamic solute-binding protein (MlaD). Through the Mla pathway, Gram-negative bacteria maintains lipid asymmetry in the outer membrane by retrograde trafficking of phospholipids from the outer membrane to the inner membrane [PMID: 19383799].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.