Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2000 May;44(5):1174-80.
doi: 10.1128/AAC.44.5.1174-1180.2000.

Syringomycin E inhibition of Saccharomyces cerevisiae: requirement for biosynthesis of sphingolipids with very-long-chain fatty acids and mannose- and phosphoinositol-containing head groups

Affiliations

Syringomycin E inhibition of Saccharomyces cerevisiae: requirement for biosynthesis of sphingolipids with very-long-chain fatty acids and mannose- and phosphoinositol-containing head groups

S D Stock et al. Antimicrob Agents Chemother. 2000 May.

Abstract

Syringomycin E is an antifungal cyclic lipodepsinonapeptide that inhibits the growth of Saccharomyces cerevisiae by interaction with the plasma membrane. A screen conducted to find the yeast genes necessary for its fungicidal action identified two novel syringomycin E response genes, SYR3 and SYR4. A syr3 mutant allele was complemented by ELO2 and ELO3. These genes encode enzymes that catalyze the elongation of sphingolipid very long chain fatty acids. Tetrad analysis showed that SYR3 was ELO2. Strains with deletions of SYR3/ELO2 and ELO3 were resistant to syringomycin E, and lipid analyses of both mutants revealed shortened fatty acid chains and lower levels of sphingolipids. SYR4 was identified by Tn5 inactivation of genomic library plasmids that complemented a syr4 mutant allele. SYR4 was found to be identical to IPT1, which encodes the terminal sphingolipid biosynthetic enzyme, mannosyl-diinositolphosphoryl-ceramide synthase. Deletion Deltasyr4/ipt1 strains were viable, were resistant to syringomycin E, did not produce mannosyl-diinositolphosphoryl-ceramide, and accumulated mannosyl-inositolphosphoryl-ceramide. Accumulation of mannosyl-inositolphosphoryl-ceramide was not responsible for resistance since a temperature-sensitive secretory pathway mutant (sec14-3(ts)) accumulated this sphingolipid and was sensitive to syringomycin E. Finally, Deltacsg1/sur1 and Deltacsg2 strains defective in the transfer of mannose to inositolphosphoryl-ceramide were resistant to syringomycin E. These findings show that syringomycin E growth inhibition of yeast is promoted by the production of sphingolipids with fully elongated fatty acid chains and the mannosyl and terminal phosphorylinositol moieties of the polar head group.

PubMed Disclaimer

Figures

FIG. 1
FIG. 1
HPLC analysis of fatty acid derivatives from elo2 and elo3 syringomycin E-resistant mutants. Shown are the HPLC profiles of the phenacyl fatty acid derivatives of strains W303C (ELO2 ELO3), W303-Δelo2, and W303-Δelo3. Twenty microliters from each extract was analyzed as described in Materials and Methods.
FIG. 2
FIG. 2
Sphingolipid analysis of strains with Δelo2 and Δelo3 deletions. An autoradiogram of a thin-layer chromatographic plate with separated 32P-labeled sphingolipids from W303C (ELO2 ELO3), W303-Δelo2, and W303-Δelo3 is shown (A). The radiolabeled spots were scraped; and IPC (filled bar), MIPC (grey bar), and M(IP)2C (blank bar) were quantitated (B). Data are from three separate experiments, and the error bars represent standard deviations.
FIG. 3
FIG. 3
Sphingolipid analysis of a strain with the Δsyr4/ipt1 deletion. The results of two-dimensional thin-layer chromatography of 32P-labeled lipids of W303H (Δsyr4/ipt1) (A) and W303I (SYR4/IPT1) (B) are shown.
FIG. 4
FIG. 4
Quantification of sphingolipids in a strain with the Δsyr4/ipt1 deletion. Strains W303I (SYR4/IPT1) and W303H (Δsyr4/ipt1) were labeled with [32P]H3PO4; and the sphingolipids IPC (filled bar), MIPC (grey bar), and M(IP)2C (open bar) were extracted and quantified as described in Materials and Methods. ∗, M(IP)2C was not detected in extracts from strain W303H (Δsyr4/ipt1). Data were obtained from three separate experiments. Error bars represent standard deviations.
FIG. 5
FIG. 5
Syringomycin E sensitivity of MIPC-accumulating strain CTY1-1A (sec14-3ts). Strains CTY1-1A (sec14-3ts), CTY-182 (SEC14), and W303H (Δsyr4/ipt1) were plated onto YPD agar medium containing 0, 0.2, 0.4, or 0.8 μg of syringomycin E per ml and were grown at a permissive temperature (28°C).
FIG. 6
FIG. 6
Effects of CSG1 and CSG2 deletions on sphingolipid composition and syringomycin E sensitivity. (A) Thin-layer chromatograph of sphingolipids of strains with Δcsg1 and Δcsg2 deletions. Yeast strains were grown and labeled in YPD medium containing 10 μCi of [32P]phosphoric acid per ml for 16 h. Lipids were extracted, deacylated with methylamine reagent, and analyzed by thin-layer chromatography. Lane 1, 39alt22A (CSG1 CSG2); lane 2, 39alt22A Δcsg1 (csg1::LEU2 CSG2); lane 3, TDY2037 (CSG1 CSG2); lane 4, TDY2038 (CSG1 csg2::LEU2). (B) Syringomycin E sensitivity of csg1 and csg2 strains. Five colonies of each strain were plated onto YPD medium with 0.5 μg of syringomycin E per ml. The strains shown are as follows: CSG1, strain 39alt22A; Δcsg1, strain 39alt22AΔcsg1; CSG2, strain TDY2037; Δcsg2, strain TDY2038.

Similar articles

Cited by

References

    1. Altschul S F, Gish W, Miller W, Myers E W, Lipman D J. Basic local alignment search tool. J Mol Biol. 1990;215:403–410. - PubMed
    1. Ballio A, Bossa F, Di Giorgio D, Ferranti P, Paci M, Scaloni A, Segre A, Strobel G. Novel bioactive lipodepsipeptides from Pseudomonas syringae: the pseudomycins. FEBS Lett. 1994;355:96–100. - PubMed
    1. Bankaitis V A, Malehorn D E, Emr S D, Greene R. The Saccharomyces cerevisiae SEC14 gene encodes a cytosolic factor that is required for transport of secretory proteins from the yeast Golgi complex. J Cell Biol. 1989;108:1271–1281. - PMC - PubMed
    1. Beeler T J, Fu D, Rivera J, Monaghan E, Gable K, Dunn T M. SUR1 (CSG1/BCL21), a gene necessary for growth of Saccharomyces cerevisiae in the presence of high Ca2+ concentrations at 37°C, is required for mannosylation of inositolphosphorylceramide. Mol Gen Genet. 1997;255:570–579. - PubMed
    1. Bull C T, Wadsworth M L, Sorensen K N, Takemoto J Y, Austin R K, Smilanick J L. Syringomycin E produced by biological control agents controls green mold on lemons. Biol Control. 1998;12:89–95.

Publication types

MeSH terms

Substances

LinkOut - more resources