CATH Classification

Domain Context

CATH Clusters

Superfamily NAD(P)-binding Rossmann-like Domain
Functional Family

Enzyme Information

2.5.1.44
Homospermidine synthase.
based on mapping to UniProt O32323
(1) 2 putrescine = sym-homospermidine + NH(3) + H(+). (2) Putrescine + spermidine = sym-homospermidine + propane-1,3-diamine.
-!- The reaction of this enzyme occurs in three steps, with some of the intermediates presumably remaining enzyme-bound: NAD(+)-dependent dehydrogenation of putrescine, transfer of the 4-aminobutylidene group from dehydroputrescine to a second molecule of putrescine and reduction of the imine intermediate to form homospermidine. -!- Hence the overall reaction is transfer of a 4-aminobutyl group. -!- Differs from EC 2.5.1.45, which cannot use putrescine as donor of the aminobutyl group.

UniProtKB Entries (1)

O32323
HSS_BLAVI
Blastochloris viridis
Homospermidine synthase

PDB Structure

PDB 4XQ9
External Links
Method X-RAY DIFFRACTION
Organism
Primary Citation
Comprehensive Structural Characterization of the Bacterial Homospermidine Synthase-an Essential Enzyme of the Polyamine Metabolism.
Krossa, S., Faust, A., Ober, D., Scheidig, A.J.
Sci Rep