Biochemical characterization and homology modeling of polyamine oxidase from cyanobacterium Synechocystis sp. PCC 6803.

A1 Originalartikel i en vetenskaplig tidskrift (referentgranskad)


Interna författare/redaktörer


Publikationens författare: Samasil K, Lopes de Carvalho L, Mäenpää P, Salminen TA, Incharoensakdi A
Förläggare: Elsevier
Publiceringsår: 2017
Tidskrift: Plant Physiology and Biochemistry
Tidskriftsakronym: Plant Physiol Biochem
Volym: 119
Artikelns första sida, sidnummer: 159
Artikelns sista sida, sidnummer: 169
ISSN: 1873-2690
eISSN: 1873-2690


Abstrakt

The intracellular polyamine contents are regulated not only by polyamine biosynthesis and transport but also by polyamine degradation catalyzed by copper-dependent amine oxidase (DAO) and FAD-dependent polyamine oxidase (PAO). The genome sequence of Synechocystis sp. PCC 6803 reveals the presence of at least one putative polyamine oxidase gene, slr5093. The open reading frame of slr5093 encoding Synechocystis polyamine oxidase (SynPAO, E.C. 1.5.3.17) was expressed in Escherichia coli. The purified recombinant enzyme had the characteristic absorption spectrum of a flavoprotein with absorbance peaks at 380 and 450 nm. The optimum pH and temperature for the oxidation of both spermidine and spermine are 8.5 and 30 °C, respectively. The enzyme catalyzed the conversion of spermine and spermidine to spermidine and putrescine, respectively, with higher catalytic efficiency when spermine served as substrate. These results suggest that SynPAO is a polyamine oxidase involved in a polyamine back-conversion pathway. Based on the structural analysis, Gln94, Tyr403 and Thr440 in SynPAO are predicted to be important residues in the active site.

Senast uppdaterad 2019-17-10 vid 03:41