Hydrogen Peroxide and Polyamines Act as Double Edged Swords in Plant Abiotic Stress Responses

Abstract

The specific genetic changes through which plants adapt to the multitude of environmental stresses are possible because of the molecular regulations in the system. These intricate regulatory mechanisms once unveiled will surely raise interesting questions. Polyamines and hydrogen peroxide have been suggested to be important signaling molecules during biotic and abiotic stresses. Hydrogen peroxide plays a versatile role from orchestrating physiological processes to stress response. It helps to achieve acclimatization and tolerance to stress by coordinating intra-cellular and systemic signaling systems. Polyamines, on the other hand, are low molecular weight polycationic aliphatic amines, which have been implicated in various stress responses. It is quite interesting to note that both hydrogen peroxide and polyamines have a fine line of inter-relation between them since the catabolic pathways of the latter releases hydrogen peroxide. In this review we have tried to illustrate the roles and their multifaceted functions of these two important signaling molecules based on current literature. This review also highlights the fact that over accumulation of hydrogen peroxide and polyamines can be detrimental for plant cells leading to toxicity and pre-mature cell death.

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

“…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.…”

“…Plants accumulate putrescine and other polyamines during drought (Gupta et al, 2016). Because drought stress and bacterial wilt disease both cause wilting, we investigated whether other wilt pathogens also triggered putrescine accumulation.…”

“…Polyamines have pleiotropic effects on plant physiology (Jim enez-Bremont et al, 2014;Gupta et al, 2016). To test the hypothesis that putrescine affects disease development, we treated tomato plant soil and leaves with 0.5 mM putrescine or water 3 h before stem inoculation with R. solanacearum.…”

“…Putrescine and other polyamines play pivotal and pleiotropic roles in plant biology. Polyamines stabilize membranes, proteins and nucleic acids; regulate plant growth; moderate drought stress; and participate in varied interactions with microbes (Marina et al, 2008;Hewezi et al, 2010;Kim et al, 2013;Jim enez-Bremont et al, 2014;Gupta et al, 2016). Polyamines sometimes benefit pathogens and sometimes boost plant immunity (Jim enez-Bremont et al, 2014).…”

“…Although R. solanacearum induces putrescine catabolism in a resistant host (Aribaud et al, 2010), we found that the activity of the putrescine catabolism enzyme diamine oxidase was 2.3fold repressed in R. solanacearum-infected versus healthy tomato plants. Conversely, polyamines can also reduce H 2 O 2 levels directly as antioxidants and indirectly by increasing host catalase activity (Gupta et al, 2016). It would be interesting to determine if putrescine dampens the oxidative defense response of susceptible tomato plants (Milling et al, 2011).…”