Intracellular POLYAMINE contents are regulated not only by biosynthesis and transport but also by catabolism through FAD dependent POLYAMINE oxidases (PAOs). The results of various studies on PAO proteins in developmental processes and response to environmental stresses confirm the importance of this protein in plant life; however, there is no comprehensive study of phylogenetic and structural relationships of plant PAOs. In the present study, to better understand phylogenetic and structural relationships of PAO proteins, bioinformatics analyses were performed on 58 PAO protein sequences of 15 different plant species. Multiple clusters with gene duplications were identified in both dicot and monocot-species. According to the conserved motifs obtained by MEME and MAST tools, four motifs were similar in most plant species. As there is no structural information available on PAOs, structural analyses were carried out on PAOs from Oryza sativa and Arabidopsis thaliana as representative of monocot and dicot plants, respectively. Secondary structure analysis revealed that alpha helix dominated among secondary structure elements followed by random coils, extended strand and beta turns for all sequences. Tertiary structures were predicted with SWISS-MODEL server. The best templates with high similarity that their structure determined by experimental methods were selected. To our knowledge, this is the first report of phylogenetic and structural relationships of plant PAOs. Our results may provide a theoretical basis for future studies of functional and structural details of plants PAOs.

In the present study, synthesis of new POLYAMINE ligands using vinamidinium salts in the presence of N-ethyl diisopropylamine in ethanol were reported. In the first part of this study, the synthesis of new POLYAMINE ligands has been reported, in the presence of N-ethyl diisopropylamine in ethanol in three steps: 1. Preparation of N-heteroaryl acetic acid salts, 2. Synthesis of vinamidinium salts and 3. synthesis of POLYAMINE ligands using vinamidinium salts. In the second part, from the reaction of nickel acetate with synthesized POLYAMINE compounds in DMSO as the solvent, the corresponding nickel (II) complexes were obtained and studied by UV spectroscopy.

C ontribution of POLYAMINEs (PAs) in response to cold stress (4◦ C) were studied in chickpea (Cicer arietinum L. ) genotypes. The content of putrescine (Put), spermidine (Spd), Spermine (Spd), hydrogen peroxide (H2O2) and relative expression of Arginine decarboxylase (ADC) and ornithine decarboxylase (ODC) genes that involve in Put biosynthesis pathway were investigated in cold-tolerant (Sel96th 11439) and cold-sensitive (ILC533) genotypes. In the tolerant genotype, H2O2 accumulation was gradually decreased (up to 4. 7%) from the first day to 6th day of cold stress treatment and its accumulation decreased while its accumulation in sensitive genotype increased up to 50% compared to the control. Under cold stress, as damage index (H2O2) was decresed, PA and Put content increased comparing to control conditions (up to 116%), while Put content in cold-sensitive genotype was lower compared to cold-tolerant genotype on the sixth day (up to 14%). Therefore, Put accumulates as an osmoprotectant in response to induced damage caused by cold stress. Under cold stress, increasing in Put content was accompanied by increasing of Spd and Spm comparing to control conditions (up to 66% and 69%) while, their increases in cold-tolerant genotype was more than cold-sensitive one. Also in both genotypes, under cold stress the transcript levels of ADC gene was increased up to 26-fold and the transcripts of ODC gene was increased up to 2-fold comparing to control conditions. These results showed that in chickpea under cold stress, increase of Put biosynthesis dependent on ADC pathway was dominant compared to ODC gene. Possibly increasing relative expression of the ADC gene with the production of Put improved cold tolerance mechanisim. Therefor, increasing PAs content particularly Put which is probably synthesized by the up-regulation of ADC gene, plays an important role in cold tolerance development in chickpea.

Growth, development and productivity of plants are greatly affected by various abiotic stresses. Physiological and molecular studies have shown that naturally occurring plant POLYAMINEs (PAs) are involved in conferring abiotic stress tolerance in plants. POLYAMINE oxidases (PAOs) are FAD-dependent enzymes associated with POLYAMINE catabolism in peroxisomes, the apoplast and the cytoplasm. In plants, increasing evidence supports the idea that PAO genes play essential roles in abiotic and biotic stresses responses. In this study, bioinformatic analysis identified eight putative PAO genes (VvPAO1– VvPAO8) in grape (Vitis vinifera) using the released 12×assemble grape genomic sequences. Phylogenetic analysis indicates that these VvPAOs can be classified into three subgroups as found in Arabidopsis and rice and also reveal that grape PAO proteins are more closely related to Arabidopsis than to those in rice. The VvPAO genes contained zero to nine introns and were distributed across 6 out of the 19 chromosomes in grape. Promoter analysis showed the presence of several cis-regulatory elements related to stress and hormone responses in regulatory regions, indicating their probable role in stress response. Microarraybased expression analysis of VvPAO orthologs in Arabidopsis under abiotic stresses showed that transcript levels of PAO genes were up-regulated significantly by such treatments, indicating their vital roles during stress adaptation. The results obtained provide basic information for future research on the functions of PAO genes in grape.

Introduction: Cherry is one of the most popular and important horticultural products for the food processing industry. Since POLYAMINEs compounds in postharvest processing have a special role, this study was conducted to examine the effect of POLYAMINEs on the firmness and the shelf life of cherries after harvesting.Materials and Methods: In this study, 16 trees of 19 years old with the same growth condition were randomly selected. After selecting the healthy branches the external parts were treated with two types of POLYAMINEs, spermidine and putrescine in triplicate orders. The former was applied at the concentrations of 0.1, 0.5 and 1 mM and the latter at 0.5 and 1 mM. External applications of POLYAMINEs were carried out in three phenological stages, 5 to 10 days before the full bloom, 5 to 10 days after the full bloom and the staining.Results: After treatment, characteristics such as fruit size, fruit weight, acidity (TA), soluble solids, percent carbohydrate, and ratio of soluble solids to acidity were measured. Spermidine 1 mM treatment increased size and weight, and also increased the amount of carbohydrates and fruit firmness.Conclusions: Treatment of POLYAMINEs, especially spermidine in 1 mM increased the firmness and durability and the effect strongly depends on the time of spraying and the concentration of these compounds.

In this research, we studied POLYAMINEs including putrescine (put), spermidine (spd) and spermine (spm) changes in three common bean (Phaseolus vulgaris) genotypes, K-S-31167, GE-288 and NAZ under drought stress. Our result showed steadily increase in putrescine (put) and spermine (spm) in all three genotypes. GE-288 genotype showed decrease and then increasing in spermidine (spd) content but K-S-31167 and NAZ genotypes showed steadily increasing in spermidine (spd). NAZ genotype accumulated putrescine more than other POLYAMINEs and showed the highest amount of putrescine in compare with other genotypes. K-S-31167 genotype accumulated the highest spermine content in compared with other genotypes. Our result showed significant increase in electrolyte leakage (EL) in all three genotypes. K-S-31167 as drought tolerant genotype and ZAZ as drought sensitive genotypes showed the lowest and the highest increase in EL, respectively.

POLYAMINEs are oxidatively deaminated by amine oxidases (AOs), including copper amine oxidases (CuAOs) and FAD-dependent POLYAMINE oxidases (PAOs). PAOs are associated with POLYAMINE catabolism in peroxisome, apoplast and cytoplasm. In plants, increasing evidences support that PAO genes play an essential roles in growth and developmental processes such as organogenesis, senescence, and also responses to abiotic and biotic stresses. The availability of the maize genome sequences has provided an excellent opportunity for whole-genome annotation, classification and comparative genomics research. In this study, through bioinformatics analysis approaches, nine putative PAO (ZmPAO1– ZmPAO9) were identified in maize genome. According to Phylogenetic analysis ZmPAOs can be divided into three major groups as found in their orthologous in Arabidopsis and rice. It is also demonstrated that maize PAO proteins are more closely related to rice than those in Arabidopsis. Gene structural analysis showed that the ZmPAOs have zero to nine introns and they are distributed across 4 out of 10 chromosomes in maize. Duplication pattern analysis shows that segmental and tandem duplication are the main reasons for maize PAOs expansion. Using public microarray data, the roles of ZmPAOs in growth and development processes were assessed. These results have been provided evidences regarding the important functions of the gene family in maize developmental regulation. These results provide a basis for further functional characterization of ZmPAOs at the tissue/developmental level and in response to stresses. Using public microarray data, ZmPAO expression profiles strongly suggested that ZmPAOs have a role in growth and development processes.

According to previous studies, salicylic acid decreases the hyperhydricity in Thymus daenesis and this event might be due to the effect on POLYAMINEs metabolism. POLYAMINE oxidase enzyme catabolizes the POLYAMINEs in the cell and one of its byproducts is hydrogen peroxide (H2O2). Purpose of this study is analyses of salicylic acid effect on POLYAMINE oxidase activity in thymus daenensis callus. In this study, the activity of POLYAMINE oxidase, content of H2O2, and responses of enzymatic antioxidant including catalase and peroxidase was measured. Results showed that salicylic acid (concentrations of 10 and 20 μ M) caused an increase in POLYAMINE oxidase activity in a dose dependent manner. In callus under salicylic acid treatment (20 μ M) a decrease in soluble peroxidase activity and an elevated H2O2 content was observed. Increase of H2O2 might be due to the influence of salicylic acid on POLYAMINE oxidase and peroxidase activities. While variations in H2O2 levels resulted in no changes of catalase activity. Regulation of H2O2 level by salicylic acid through its effect on POLYAMINE oxidase activity might contribute to ROS homeostasis, which is necessary for in vitro developmental processes in plant cells.

Objective: Human milk (HM) is the ideal food for all newborns and infants. Apart from various bioactive compounds, including cytokines, antibodies, hormones, vitamines, it also contains POLYAMINEs, such as spermine (Sp), spermidine (Spd) and putrescine (Put).Aim: The present study investigated POLYAMINE metabolism in colostrum and mature human milk by measuring the POLYAMINE oxidase (PAO) and diamine oxidase (DAO) enzyme activities, which are necessary for POLYAMINE catabolism, as well as by determining the malondialdehyde (MDA) levels, the final product of POLYAMINE biodegradation.Methods: The PAO, DAO activity and MDA levels were quantified in colostrum (1st and 2nd day) as well as in mature human milk, 30th day of lactation.Findings: We found the steady increase of PAO activity and steady decrease of DAO activity and MDA levels during first month of lactation.Conclusion: Since the products of PAO activity such as, amino aldehydes and hydrogen peroxide (H2O2) might have potential antimicrobial effects, promoting the oxidative stress, it is likely that human milk PAO throughout the lactation period, contributes to the protective effects of human milk.