In enzymology, a putrescine N-methyltransferase () is an

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...

that catalyzes the

chemical reaction A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the pos ...

:S-adenosyl-L-methionine + putrescine

\rightleftharpoons

S-adenosyl-L-homocysteine + N-methylputrescine Thus, the two substrates of this enzyme are

S-adenosyl methionine ''S''-Adenosyl methionine (SAM), also known under the commercial names of SAMe, SAM-e, or AdoMet, is a common cosubstrate involved in methyl group transfers, transsulfuration, and aminopropylation. Although these anabolic reactions occur throug ...

and

putrescine Putrescine is an organic compound with the formula (CH2)4(NH2)2. It is a colorless solid that melts near room temperature. It is classified as a diamine. Together with cadaverine, it is largely responsible for the foul odor of putrefying flesh, ...

, whereas its two

products Product may refer to: Business * Product (business), an item that serves as a solution to a specific consumer problem. * Product (project management), a deliverable or set of deliverables that contribute to a business solution Mathematics * Produ ...

are S-adenosylhomocysteine and N-methylputrescine. This enzyme belongs to the family of

transferase A transferase is any one of a class of enzymes that catalyse the transfer of specific functional groups (e.g. a methyl or glycosyl group) from one molecule (called the donor) to another (called the acceptor). They are involved in hundreds of ...

s, specifically those transferring one-carbon group methyltransferases. The

systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivial ...

of this enzyme class is S-adenosyl-L-methionine:putrescine N-methyltransferase. This enzyme is also called putrescine methyltransferase. This enzyme participates in

alkaloid biosynthesis ii Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar st ...

. This enzyme is important in the synthesis of many plant

alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...

s. It evolved from

spermidine synthase Spermidine synthase is an enzyme () that catalyzes the transfer of the propylamine group from ''S''-adenosylmethioninamine to putrescine in the biosynthesis of spermidine. The systematic name is S-adenosyl 3-(methylthio)propylamine:putrescine 3-a ...

References

* EC 2.1.1 Enzymes of unknown structure {{2.1-enzyme-stub