Physiological and molecular implications of plant polyamine metabolism during biotic interactions

Abstract

During ontogeny, plants interact with a wide variety of microorganisms. The association with mutualistic microbes results in benefits for the plant. By contrast, pathogens may cause a remarkable impairment of plant growth and development. Both types of plant–microbe interactions provoke notable changes in the polyamine (PA) metabolism of the host and/or the microbe, being each interaction a complex and dynamic process. It has been well documented that the levels of free and conjugated PAs undergo profound changes in plant tissues during the interaction with microorganisms. In general, this is correlated with a precise and coordinated regulation of PA biosynthetic and catabolic enzymes. Interestingly, some evidence suggests that the relative importance of these metabolic pathways may depend on the nature of the microorganism, a concept that stems from the fact that these amines mediate the activation of plant defense mechanisms. This effect is mediated mostly through PA oxidation, even though part of the response is activated by non-oxidized PAs. In the last years, a great deal of effort has been devoted to profile plant gene expression following microorganism recognition. In addition, the phenotypes of transgenic and mutant plants in PA metabolism genes have been assessed. In this review, we integrate the current knowledge on this field and analyze the possible roles of these amines during the interaction of plants with microbes.

Metabolomics of tomato xylem sap during bacterial wilt reveals Ralstonia solanacearum produces abundant putrescine, a metabolite that accelerates wilt disease

“…S10). ADCs and ODCs are rate‐determining steps in plant polyamine biosynthesis, and higher ADC and ODC transcription is correlated with increased plant putrescine production (Jiménez‐Bremont et al ., ). We measured expression of tomato polyamine biosynthesis genes in roots and stems following inoculation of unwounded roots.…”

“…Polyamines sometimes benefit pathogens and sometimes boost plant immunity (Jiménez‐Bremont et al ., ). It has been observed that ‘In plant–pathogen interactions, the organism that takes control of polyamine metabolism has the advantage’ (Jiménez‐Bremont et al ., ). Although the specific roles of polyamines in plant–microbe interactions are uncertain, there are hints.…”

“…Although the specific roles of polyamines in plant–microbe interactions are uncertain, there are hints. When polyamines contribute to plant defense, it is often because their catabolism releases the plant defense signal H 2 O 2 (Marina et al ., ; Jiménez‐Bremont et al ., ; Gupta et al ., ). Although R. solanacearum induces putrescine catabolism in a resistant host (Aribaud et al ., ), we found that the activity of the putrescine catabolism enzyme diamine oxidase was 2.3‐fold repressed in R. solanacearum ‐infected versus healthy tomato plants.…”

Molecular functions of Xanthomonas type III effector AvrBsT and its plant interactors in cell death and defense signaling

“…PAs, including putrescine, spermidine, and spermine are positively charged secondary metabolites that are associated with plant resistance to microbial pathogens (Walters 2003;Jimenez-Bremont et al 2014). BiFC and Co-IP analyses of Agrobacterium-mediated transient expression in N. benthamiana leaves verified the physical interaction of AvrBsT with CaADC1 in planta (Kim et al 2013b).…”

The Role of Polyamines in Plant Disease Resistance

“…In this review, I briefly summarize current knowledge of the role of PAs in disease resistance. More comprehensive reviews of PAs in biotic stress responses, including pathogenic and beneficial interactions, are available elsewhere (Jiménez-Bremont et al, 2014).…”