Peptidase family M54, also called archaemetzincins or archaelysins
Peptidase M54 (archaemetzincin or archaelysin) is a zinc-dependent aminopeptidase that contains the consensus zinc-binding sequence HEXXHXXGXXH/D and a conserved Met residue at the active site, and is thus classified as a metzincin. Archaemetzincins, first identified in archaea, are also found in bacteria and eukaryotes, including two human members, archaemetzincin-1 and -2 (AMZ1 and AMZ2). AMZ1 is mainly found in the liver and heart while AMZ2 is primarily expressed in testis and heart; both have been reported to degrade synthetic substrates and peptides. The Peptidase M54 family contains an extended metzincin concensus sequence of HEXXHXXGX3CX4CXMX17CXXC such that a second zinc ion is bound to four cysteines, thus resembling a zinc finger. Phylogenetic analysis of this family reveals a complex evolutionary process involving a series of lateral gene transfer, gene loss and genetic duplication events.
Structure:2X7M: Methanopyrus kandleri Archaemetzincin (Amza) binds two Zn ions - View structure with Cn3D
Comment:Archaemetzincins bind two zinc ions, one is coordinated by histidines and is common to all metzincins, and a second one which is coordinated by 4 cysteine residues resembling a zinc-finger motif.
Comment:Archaemetzincins have an extended conserved sequence of HEXXHXXGX3CX4CXMX17CXXC
Jiyao W et al.(2023). "The conserved domain database in 2023.",