Role of S-methylmethionine in the plant metabolism

Abstract

S-methylmethionine (SMM), a naturally occurring, biologically active compound, is a free amino acid derivative, which is increasingly recognised as playing an important part in the plant metabolism. SMM, which is synthesised from methionine, is involved in crucial processes in the S metabolism, such as the regulation of methionine and S-adenosyl methionine levels, the methylation processes taking place in cells, and the transport and storage of sulphur in certain phases of development. It is of great importance in the development of resistance to abiotic and biotic stress factors, as it is a direct precursor in the biosynthesis of the osmoprotectants and other S-containing compounds involved in defence mechanisms, while also influencing the biosynthesis of major plant hormones such as polyamines and ethylene. The present paper discusses our increasing understanding of the role played by SMM in the plant metabolism and its possible role in the improvement of traits that enable plants to overcome stress.

Effect of S-methylmethionine on the photosynthesis in maize at different chilling temperatures

“…In the course of the methionine cycle this compound is able to revert to methionine through a transmethylation reaction involving homocysteine. SMM consequently plays a role in regulating the levels of both methionine and S-adenosyl methionine [3][4][5], participates in methylation processes within the cell and plays an important role in the transportation and storage of sulphur [6,7]. It is able to moderate the damaging effects of numerous stressors by enhancing the production of dimethyl sulphopropionate which acts as an osmo-and cryoprotectant [8,9], and by increasing the biosynthesis of polyamines, and by regulating ethylene production [10][11][12].…”

Production of volatiles by the red seaweed Gelidium arbuscula (Rhodophyta): emission of ethylene and dimethyl sulfide

“…Together with DMS and its precursor DMSP, SAM and SMM are related sulfonium compounds derived from methionine (Szegö et al. ). It was proposed that DMSP that accumulates in plants and marine algae acts as an osmoprotectant (Kocsics et al.…”

“…Besides its generation by DMSP lyase, higher plants can also generate DMS through an intermediate step involving S‐methylmethionine (SMM; Szegö et al. , Ogawa and Mitsuya ). An alternative metabolic route relates DMS synthesis to ethylene synthesis.…”

Interactions of S-methylmethionine and UV-B can modify the defence mechanisms induced in maize

“…It has an important role in the sulphur metabolism, and either directly or indirectly, in the stress and disease tolerance of plants. SMM is synthesized from methionine using S-adenosyl methionine as the methyl donor and is able to revert to methionine (through a transmethylation reaction involving homocysteine) in the course of the methionine cycle (Szegő et al 2007 ). Consequently, it plays a role in regulating the levels of both methionine and S-adenosyl methionine.…”

“…SMM participates in methylation processes within the cell and plays an important role in the transportation and storage of sulphur (Gigolashvili and Kopriva 2014 ). It is able to moderate the damaging effects of numerous stressors by enhancing the production of dimethyl sulphopropionate, which acts as an osmo-and cryoprotectant (Ogawa and Mitsuya 2012 ), by increasing the biosynthesis of polyamines, and by regulating ethylene production (Ko et al 2004 ;Szegő et al 2007 ).…”