Reaction: S-adenosyl-L-methionine + (2R)-2-hydroxy-4-(methylsulfanyl)butanoate = S-adenosyl-L-homocysteine + (2R)-4-(dimethylsulfaniumyl)-2-hydroxybutanoate
Other name(s): dsyB (gene name); methylthiohydroxybutyrate methyltransferase; MTHB methyltransferase
Systematic name: S-adenosyl-L-methionine:(2R)-2-hydroxy-4-(methylsulfanyl)butanoate S-methyltransferase
Comments: The enzyme, characterized from the marine bacterium Labrenzia aggregata, participates in the biosynthesis of dimethylsulfoniopropanoate (DMSP). A eukaryotic enzyme that shares little sequence similarity with the bacterial enzyme was identified in many marine phytoplankton species.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Summers, P.S., Nolte, K.D., Cooper, A.J.L., Borgeas, H., Leustek, T., Rhodes, D. and Hanson, A.D. Identification and stereospecificity of the first three enzymes of 3-dimethylsulfoniopropionate biosynthesis in a chlorophyte alga. Plant Physiol. 116 (1998) 369-378.
2. Curson, A.R., Liu, J., Bermejo Martinez, A., Green, R.T., Chan, Y., Carrion, O., Williams, B.T., Zhang, S.H., Yang, G.P., Bulman Page, P.C., Zhang, X.H. and Todd, J.D. Dimethylsulfoniopropionate biosynthesis in marine bacteria and identification of the key gene in this process. Nat. Microbiol. 2 (2017) 17009. [PMID: 28191900]
3. Kageyama, H., Tanaka, Y., Shibata, A., Waditee-Sirisattha, R. and Takabe, T. Dimethylsulfoniopropionate biosynthesis in a diatom Thalassiosira pseudonana: Identification of a gene encoding MTHB-methyltransferase. Arch. Biochem. Biophys. 645 (2018) 100-106. [PMID: 29574051]
4. Curson, A.RJ., Williams, B.T., Pinchbeck, B.J., Sims, L.P., Martinez, A.B., Rivera, P.PL., Kumaresan, D., Mercade, E., Spurgin, L.G., Carrion, O., Moxon, S., Cattolico, R.A., Kuzhiumparambil, U., Guagliardo, P., Clode, P.L., Raina, J.B. and Todd, J.D. DSYB catalyses the key step of dimethylsulfoniopropionate biosynthesis in many phytoplankton. Nat. Microbiol. 3 (2018) 430-439. [PMID: 29483657]