Abstract
In the flowering plant Wollastonia biflora (L.) DC. the first step in 3-dimethylsulfoniopropionate (DMSP) synthesis is conversion of methionine to S-methylmethionine (SMM) and the last is oxidation of 3-dimethylsulfoniopropionaldehyde (DMSP-ald) (F. James, L. Paquet, S.A. Sparace, D.A. Gage, A.D. Hanson [1995] Plant Physiol 108: 1439-1448). DMSP-ald was shown to undergo rapid, spontaneous decomposition to dimethylsulfide and acrolein. However, it was stable enough (half-life [greater than or equal to] 1 h) in tertiary amine buffers to use as a substrate for enzyme assays. A dehydrogenase catalyzing DMSP-ald oxidation was detected in extracts of W. biflora mesophyll protoplasts. This enzyme had a high affinity for DMSP-ald (Km = 1.5 [mu]M), was subject to substrate inhibition, preferred NAD to NADP, and was immunologically related to plant betaine aldehyde dehydrogenases. After fractionation of protoplast lysates, [greater than or equal to]90% of DMSP-ald dehydrogenase activity was recovered from the chloroplast stromal fraction, whereas the enzyme that mediates SMM synthesis, S-adenosylmethionine:methionine S-methyltransferase, was found exclusively in the cytosolic fraction. Immunohistochemical analysis confirmed that the S-methyltransferase was cytosolic. Intact W. biflora chloroplasts were able to metabolize supplied [35S]SMM to [35S]DMSP. These findings indicate that SMM is made in the cytosol, imported into the chloroplast, and there converted successively to DMSP-ald and DMSP.
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- Bohnert H. J., Nelson D. E., Jensen R. G. Adaptations to Environmental Stresses. Plant Cell. 1995 Jul;7(7):1099–1111. doi: 10.1105/tpc.7.7.1099. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cline K. Import of proteins into chloroplasts. Membrane integration of a thylakoid precursor protein reconstituted in chloroplast lysates. J Biol Chem. 1986 Nov 5;261(31):14804–14810. [PubMed] [Google Scholar]
- Edwards G. E., Robinson S. P., Tyler N. J., Walker D. A. Photosynthesis by isolated protoplasts, protoplast extracts, and chloroplasts of wheat: influence of orthophosphate, pyrophosphate, and adenylates. Plant Physiol. 1978 Aug;62(2):313–319. doi: 10.1104/pp.62.2.313. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Eichel J., González J. C., Hotze M., Matthews R. G., Schröder J. Vitamin-B12-independent methionine synthase from a higher plant (Catharanthus roseus). Molecular characterization, regulation, heterologous expression, and enzyme properties. Eur J Biochem. 1995 Jun 15;230(3):1053–1058. doi: 10.1111/j.1432-1033.1995.tb20655.x. [DOI] [PubMed] [Google Scholar]
- Ellis K. J., Morrison J. F. Buffers of constant ionic strength for studying pH-dependent processes. Methods Enzymol. 1982;87:405–426. doi: 10.1016/s0076-6879(82)87025-0. [DOI] [PubMed] [Google Scholar]
- GREENE R. C. Biosynthesis of dimethyl-beta-propiothetin. J Biol Chem. 1962 Jul;237:2251–2254. [PubMed] [Google Scholar]
- Hanson A. D., Rivoal J., Paquet L., Gage D. A. Biosynthesis of 3-dimethylsulfoniopropionate in Wollastonia biflora (L.) DC. Evidence that S-methylmethionine is an intermediate. Plant Physiol. 1994 May;105(1):103–110. doi: 10.1104/pp.105.1.103. [DOI] [PMC free article] [PubMed] [Google Scholar]
- James F., Nolte K. D., Hanson A. D. Purification and properties of S-adenosyl-L-methionine:L-methionine S-methyltransferase from Wollastonia biflora leaves. J Biol Chem. 1995 Sep 22;270(38):22344–22350. doi: 10.1074/jbc.270.38.22344. [DOI] [PubMed] [Google Scholar]
- James F., Paquet L., Sparace S. A., Gage D. A., Hanson A. D. Evidence implicating dimethylsulfoniopropionaldehyde as an intermediate in dimethylsulfoniopropionate biosynthesis. Plant Physiol. 1995 Aug;108(4):1439–1448. doi: 10.1104/pp.108.4.1439. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mudd S. H., Datko A. H. The S-Methylmethionine Cycle in Lemna paucicostata. Plant Physiol. 1990 Jun;93(2):623–630. doi: 10.1104/pp.93.2.623. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nolte K. D., Koch K. E. Companion-Cell Specific Localization of Sucrose Synthase in Zones of Phloem Loading and Unloading. Plant Physiol. 1993 Mar;101(3):899–905. doi: 10.1104/pp.101.3.899. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rathinasabapathi B., McCue K. F., Gage D. A., Hanson A. D. Metabolic engineering of glycine betaine synthesis: plant betaine aldehyde dehydrogenases lacking typical transit peptides are targeted to tobacco chloroplasts where they confer betaine aldehyde resistance. Planta. 1994;193(2):155–162. doi: 10.1007/BF00192524. [DOI] [PubMed] [Google Scholar]
- Wallsgrove R. M., Lea P. J., Miflin B. J. Intracellular localization of aspartate kinase and the enzymes of threonine and methionine biosynthesis in green leaves. Plant Physiol. 1983 Apr;71(4):780–784. doi: 10.1104/pp.71.4.780. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Weigel P., Lerma C., Hanson A. D. Choline oxidation by intact spinach chloroplasts. Plant Physiol. 1988 Jan;86(1):54–60. doi: 10.1104/pp.86.1.54. [DOI] [PMC free article] [PubMed] [Google Scholar]
