SAM2 encodes the second methionine S-adenosyl transferase in Saccharomyces cerevisiae: physiology and regulation of both enzymes.

Thomas, Dominique; Rothstein, Rodney; Rosenberg, Nurit; Surdin-Kerjan, Yolande

doi:10.1128/mcb.8.12.5132

Cited by 135 publications

(120 citation statements)

References 39 publications

Supporting

Mentioning

114

Contrasting

Order By: Relevance

“…In S. cerevisiae the SAM1 and SAM2 genes encode two distinct forms of AdoMet synthetase (45) that are highly homologous (83% similarity) (42). DNA microarray analysis indicate the transcriptional abundance of SAM1 and SAM2 genes increased by 2.7-and 6.9-fold, respectively, following treatment with Me 2 SO (Table I).…”

Section: Me 2 So Concentration and Duration Of Exposure-s Cerevisiaementioning

confidence: 99%

“…AdoHcy is converted to homocysteine in the methionine biosynthesis pathway, which is then remethylated to methionine by methionine synthetase (MET17/25 and MET6). AdoMet is regenerated by AdoMet synthetase (SAM) (42,43). Because AdoMet is the methyl donor in hundreds of transmethylation reactions of nucleic acids, proteins, and lipids (44), we propose that in Me 2 SO-treated cells integration of this pathway with the biosynthesis of phospholipids helps maintain membrane integrity.…”

Section: Me 2 So Concentration and Duration Of Exposure-s Cerevisiaementioning

confidence: 99%

See 1 more Smart Citation

Dimethyl Sulfoxide Exposure Facilitates Phospholipid Biosynthesis and Cellular Membrane Proliferation in Yeast Cells

Murata¹,

Watanabe²,

Sato³

et al. 2003

Journal of Biological Chemistry

View full text Add to dashboard Cite

Me 2 SO is a polar solvent that is widely used in biochemistry, pharmacology, and industry. Although there are several reports in the literature concerning the biological effects of Me 2 SO, the total cellular response remains unclear. In this paper, DNA microarray technology combined with the hierarchical clustering bioinformatics tool was used to assess the effects of Me 2 SO on yeast cells. We found that yeast exposed to Me 2 SO increased phospholipid biosynthesis through up-regulated gene expression. It was confirmed by Northern blotting that the level of INO1 and OPI3 gene transcripts, encoding key enzymes in phospholipid biosynthesis, were significantly elevated following treatment with Me 2 SO. Furthermore, the phospholipid content of the cells increased during exposure to Me 2 SO as shown by conspicuous incorporation of a lipophilic fluorescent dye (3,3 -dihexyloxacarbocyanine iodide) into the cell membranes. From these results we propose that Me 2 SO treatment induces membrane proliferation in yeast cells to alleviate the adverse affects of this chemical on membrane integrity.Dimethyl sulfoxide (Me 2 SO) 1 is widely used as a solvent in the chemical industry and as a cryoprotectant in biotechnology. It is present in the environment as a waste product of the paper industry and from the production of dimethyl sulfide (DMS) and also arises from the degradation of sulfur-containing pesticides (1). In addition, Me 2 SO forms naturally from photooxidation of DMS in the atmosphere and from degradation of DMS by phytoplankton in the marine environment (2). Because Me 2 SO has low volatility and is highly hygroscopic, it is rapidly scavenged from the atmosphere by rain and returned to earth, and thereby plays a role in the global sulfur cycle (1, 3).Microorganisms, including both prokaryotes and eukaryotes, have the capability of reducing Me 2 SO and can utilize it as a terminal electron acceptor during anaerobic growth (4 -6). Me 2 SO reductase from Escherichia coli and Rhodobacter sphaeroides catalyzes the reduction of Me 2 SO to DMS (7-9). This enzyme, which contains a molybdenum cofactor at the active center, is well characterized at the biochemical, biophysical, and molecular level and provides an excellent model system for investigating the structure and mechanism of electron transfer chain complexes (1, 10). Saccharomyces cerevisiae has a number of NADPH-dependent enzymes that, in conjunction with methionine sulfoxide reductase (MXR1), can reduce Me 2 SO to DMS (11).In E. coli, the combination of divalent cations as Ca 2ϩ and Me 2 SO has been shown to stimulate the efficiency of DNA transfer into the cell (12). In the case of mammalian cells, it is reported that the transfection efficiency is increased by Me 2 SO treatment after electroporation (13). The exact mechanism of how Me 2 SO increases membrane permeability leading to DNA uptake is unclear.In mammalian cells Me 2 SO (2% (v/v)) can induce morphological changes, for example in mouse erythroleukemic cells (14), or cause differentiation, for example ...

show abstract

Section: Me 2 So Concentration and Duration Of Exposure-s Cerevisiaementioning

confidence: 99%

Section: Me 2 So Concentration and Duration Of Exposure-s Cerevisiaementioning

confidence: 99%

Dimethyl Sulfoxide Exposure Facilitates Phospholipid Biosynthesis and Cellular Membrane Proliferation in Yeast Cells

Murata¹,

Watanabe²,

Sato³

et al. 2003

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…Expression of the SAM2 gene is induced by the presence of excess methionine in the growth medium, while expression of the SAM1 gene from S. cereVisiae is repressed (16), and there is no problem of product inhibition observed in use of the Escherichia coli SAM synthetase (17). The synthetase encoded by SAM2 was intracellularly expressed in E. coli (18).…”

Section: Introductionmentioning

confidence: 99%

Expression of Secreted His-Tagged S-adenosylmethionine Synthetase in the Methylotrophic Yeast Pichia pastoris and Its Characterization, One-Step Purification, and Immobilization

Luo¹,

Yuan²,

Luo³

et al. 2008

Biotechnol. Prog.

View full text Add to dashboard Cite

S-Adenosylmethionine synthetase (SAM synthetase) catalyzes the synthesis of S-adenosylmethionine (SAM), which plays an important role in cellular functions such as methylation, sulfuration, and polyamine synthesis. To develop a simple and effective way to enzymatically synthesize and produce SAM, a soluble form of SAM synthetase encoded by SAM2 from Saccharomyces cereVisiae was successfully produced at high level (∼200 mg/L) by the recombinant methylotrophic yeast Pichia pastoris. The secreted His 6 -tagged SAM synthetase was purified in a single chromatography step with a yield of approximately 82% for the total activity. The specific activity of the purified synthetase was 23.84 U/mg. The recombinant SAM synthetase could be a kind of allosteric enzyme with negative regulation. The enzyme functioned optimally at a temperature of 35°C and pH 8.5. The stability of the recombinant synthetase and the effectiveness of different factors in preventing the enzyme from inactivation were also studied. Additional experiments were performed in which the recombinant SAM synthetase was purified and immobilized in one step using immobilized metal-chelate affinity chromatography. The immobilized synthetase was found to be 40.4% of the free enzyme activity in catalyzing the synthesis of SAM from DL-Met and ATP.

show abstract

“…It has been shown that the presence of SAM in the growth medium represses the expression of one of the sam-s genes in yeast and that SAM is a corepresor in the biosynthesis of methionine in Escherichia Coli (SaintGirons et al, 1986;Thomas et al, 1988;Rafferty et al, 1989). A reduced leve1 of this f a m r in neighboring cells would upregulate the expression of the endogenous sam* genes to the putative threshold level necessary to elaborate the switch to the suppressed state.…”

Section: Controlled By Sam-s Activitymentioning

confidence: 99%

Distinct phenotypes generated by overexpression and suppression of S-adenosyl-L-methionine synthetase reveal developmental patterns of gene silencing in tobacco.

et al. 1994

View full text Add to dashboard Cite

S-Adenosyl-L-methionine synthetase (SAM-S) catalyzes the conversion of L-methionine and ATP into S-adenosyl-L-methionine. Tobacco plants that were transformed with a construct allowing high transcription levels of an Arabidopsis sam-s gene could be grouped into two main classes based on their morphology. One class developed yellow-green leaves and had high SAM-S activity and transgene mRNA levels, whereas the other class was stunted and had leatherlike leaves, very low SAM-S activity, and suppressed mRNA leve1 of the transgene. Because both overexpression and silencing of transgene expression led to distinct, abnormal phenotypes, the developmental pattern of transgene silencing was visualized. In the lower leaves, the suppressed phenotype was associated with the veins. In successive leaves, the area of the suppressed tissue increased until all newly developed leaves displayed the suppressed phenotype. In this study, a hypothesis is presented for this developmental gene silencing. Furthermore, transgenic plants with suppressed SAM-S activity had a characteristic smell, a consequence of the accumulation of L-methionine that is converted into the volatile methanethiol.

show abstract

SAM2 encodes the second methionine S-adenosyl transferase in Saccharomyces cerevisiae: physiology and regulation of both enzymes.

Cited by 135 publications

References 39 publications

Dimethyl Sulfoxide Exposure Facilitates Phospholipid Biosynthesis and Cellular Membrane Proliferation in Yeast Cells

Dimethyl Sulfoxide Exposure Facilitates Phospholipid Biosynthesis and Cellular Membrane Proliferation in Yeast Cells

Expression of Secreted His-Tagged S-adenosylmethionine Synthetase in the Methylotrophic Yeast Pichia pastoris and Its Characterization, One-Step Purification, and Immobilization

Distinct phenotypes generated by overexpression and suppression of S-adenosyl-L-methionine synthetase reveal developmental patterns of gene silencing in tobacco.

Contact Info

Product

Resources

About