Defining novel plant polyamine oxidase subfamilies through molecular modeling and sequence analysis

CESAR DANIEL BORDENAVE; CAROLINA GRANADOS MENDOZA; JUAN FRANCISCO GIMENEZ-BREMONT; ANDRES GARRIZ; ANDRES ALBERTO RODRIGUEZ (CORRESPONDING AUTHOR)

BMC EVOLUTIONARY BIOLOGY

BIOMED CENTRAL LTD

Lugar: Londres; Año: 2019

1471-2148

Background: The polyamine oxidases (PAOs) catabolize the oxidative deamination of thepolyamines (PAs) spermine (Spm) and spermidine (Spd). Most of the phylogeneticstudies performed to analyze the plant PAO family took into account only alimited number and/or taxonomic representation of plant PAOs sequences.Results: Here, we constructed a plant PAO protein sequencedatabase and identified four subfamilies. Subfamily PAO backconversion 1 (PAObc1) was present on every lineage included in these analyses,suggesting that BC-type PAOs might play an important role in plants, despiteits precise function is unknown. Subfamily PAObc2 was exclusively present invascular plants, suggesting that t-Spm oxidase activity might play an importantrole in the development of the vascular system. The only terminal catabolism(TC) PAO subfamily (subfamily PAOtc) was lost in Superasterids but it waspresent in all other land plants. This indicated that the TC-type reactions arefundamental for land plants and that their function could being taken over byother enzymes in Superasterids. Subfamily PAObc3 was the result of a geneduplication event preceding Angiosperm diversification, followed by a gene extinctionin Monocots. Differential conserved protein motifs were found for eachsubfamily of plant PAOs. The automatic assignment using these motifs was foundto be comparable to the assignment by rough clustering performed on this work. Conclusions: The results presented in this work revealed thatplant PAO family is bigger than previously conceived. Also, they delineateimportant background information for future specific structure-function andevolutionary investigations and lay a foundation for the deepercharacterization of each plant PAO subfamily.