Molecular Cloning and Expression of PutrescineN-Methyltransferase from the Hairy Roots ofAnisodus tanguticus

Abstract
A full-length cDNA encoding putrescine N-methyltransferase (PMT) was isolated from the hairy roots of A. tanguticus. Nucleotide sequence analysis of the cloned cDNA revealed an open reading frame of 1017 bp encoding 338 amino acids with high homology to other known PMTs. A. tanguticus PMT was expressed in Escherichia coli. The recombinant AtPMT was purified and exhibited S-adenosyl-methionine-dependent N-methyltransferase activity.