The bacterial protein Mac 1 adopts an alpha/beta fold, with 14 beta strands and 9 alpha helices. The N-terminal domain is made up predominantly of alpha helices, whereas the C-terminal domain consists predominantly of beta sheets. Mac 1 blocks polymorphonuclear opsonophagocytosis, inhibits the production of reactive oxygen species and contains IgG endopeptidase activity.
Jiyao W et al.(2023). "The conserved domain database in 2023.",