A Gene Cluster for Biosynthesis of Mannosylerythritol Lipids Consisted of 4-O-β-D-Mannopyranosyl-(2R,3S)-Erythritol as the Sugar Moiety in a Basidiomycetous Yeast Pseudozyma tsukubaensis.
Mannosylerythritol lipids (MELs) belong to the glycolipid biosurfactants and are produced by various fungi. The basidiomycetous yeast Pseudozyma tsukubaensis produces diastereomer type of MEL-B, which contains 4-O-β-D-mannopyranosyl-(2R,3S)-erythritol (R-form) as the sugar moiety. In this respect it differs from conventional type of MELs, which contain 4-O-β-D-mannopyranosyl-(2S,3R)-erythritol (S-form) as the sugar moiety. While the biosynthetic gene cluster for conventional type of MELs has been previously identified in Ustilago maydis and Pseudozyma antarctica, the genetic basis for MEL biosynthesis in P. tsukubaensis is unknown. Here, we identified a gene cluster involved in MEL biosynthesis in P. tsukubaensis. Among these genes, PtEMT1, which encodes erythritol/mannose transferase, had greater than 69% identity with homologs from strains in the genera Ustilago, Melanopsichium, Sporisorium and Pseudozyma. However, phylogenetic analysis placed PtEMT1p in a separate clade from the other proteins. To investigate the function of PtEMT1, we introduced the gene into a P. antarctica mutant strain, ΔPaEMT1, which lacks MEL biosynthesis ability owing to the deletion of PaEMT1. Using NMR spectroscopy, we identified the biosynthetic product as MEL-A with altered sugar conformation. These results indicate that PtEMT1p catalyzes the sugar conformation of MELs. This is the first report of a gene cluster for the biosynthesis of diastereomer type of MEL.
Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan.
Azusa
A
Saika
Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan.
Hideaki
H
Koike
Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan.
Tokuma
T
Fukuoka
Toyobo Co., Ltd., Tsuruga Institute of Biotechnology, Tsuruga, Fukui, Japan.
Shuhei
S
Yamamoto
Toyobo Co., Ltd., Tsuruga Institute of Biotechnology, Tsuruga, Fukui, Japan.
Takahide
T
Kishimoto
Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan.
Tomotake
T
Morita
D000595:Amino Acid Sequence; D053898:Biosynthetic Pathways / Q000235:genetics*; D066241:Carbon-13 Magnetic Resonance Spectroscopy; D002855:Chromatography, Thin Layer; D004896:Erythritol / Q000031:analogs & derivatives* / Q000378:metabolism*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics; D005800:Genes, Fungal; D006017:Glycolipids / Q000096:biosynthesis* / Q000737:chemistry; D008362:Mannosides / Q000378:metabolism*; D005810:Multigene Family; D010802:Phylogeny; D010957:Plasmids / Q000378:metabolism; D066244:Proton Magnetic Resonance Spectroscopy; D016415:Sequence Alignment; D020539:Sequence Analysis, Protein; D017386:Sequence Homology, Amino Acid; D013237:Stereoisomerism; D014587:Ustilaginales
D005656:Fungal Proteins; D006017:Glycolipids; D008362:Mannosides; C439671:mannosylerythritol lipid; D004896:Erythritol