N-terminal Xaa-Pro-Lys N-methyltransferase 1 (NTMT1)

Distributive alpha-N-methyltransferase which methylates the N-terminus of target proteins comprising the N-terminal theme [Ala/Gly/Pro/Ser]-Pro-Lys when the initiator Met is cleaved. Specifically catalyzes mono-, di- or tri-methylation of the exposed alpha-amino set of the Ala, Gly or Ser residue in the [Ala/Gly/Ser]-Pro-Lys motif and mono- or di-methylation of Pro in the Pro-Pro-Lys motif.

Some of the substrates could be primed by METTL11B-mediated monomethylation (PubMed:24090352). Catalyzes the trimethylation of this N-terminal Gly in CENPA (after elimination of Met-1).