Mannosylerythritol lipids secreted by phyllosphere yeast Pseudozyma antarctica is associated with its filamentous growth and propagation on plant surfaces.
The biological function of mannosylerythritol lipids (MELs) towards their producer, Pseudozyma antarctica, on plant surfaces was investigated. MEL-producing wild-type strain and its MEL production-defective mutant strain (ΔPaEMT1) were compared in terms of their phenotypic traits on the surface of plastic plates, onion peels, and fresh leaves of rice and wheat. While wild-type cells adhering on plastic surfaces and onion peels changed morphologically from single cells to elongated ones for a short period of about 4 h and 1 day, respectively, ΔPaEMT1 cells did not. Microscopic observation of both strains grown on plant leaf surfaces verified that the wild type colonized a significantly bigger area than that of ΔPaEMT1. However, when MELs were exogenously added to the mutant cells on plant surfaces, their colonized area became enlarged. High-performance liquid chromatography analysis revealed a secretion of higher amount of MELs in the cell suspension incubated with wheat leaf cuttings compared to that in the suspension without cuttings. Transcriptional analysis by real-time reverse transcriptase PCR verified that the expression of erythritol/mannose transferase gene and MELs transporter gene of P. antarctica increased in the cells inoculated onto wheat leaves at 4, 6, and 8 days of incubation, indicating a potential of P. antarctica to produce MELs on the leaves. These findings demonstrate that MELs produced by P. antarctica on plant surfaces could be expected to play a significant role in fungal morphological development and propagation on plant surfaces.
National Institute for Agro-Environmental Sciences (NIAES), 3-1-3, Kan-nondai, Tsukuba, Ibaraki, 305-8604, Japan.
Shigenobu
S
Yoshida
Tomotake
T
Morita
Yukiko
Y
Shinozaki
Takashi
T
Watanabe
Yuka
Y
Sameshima-Yamashita
Motoo
M
Koitabashi
Dai
D
Kitamoto
Hiroko
H
Kitamoto
D002448:Cell Adhesion; D020869:Gene Expression Profiling; D005964:Glucosyltransferases / Q000032:analysis; D006017:Glycolipids / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000378:metabolism; D008853:Microscopy; D019697:Onions; D012275:Oryza; D018515:Plant Leaves / Q000382:microbiology*; D010969:Plastics; D013997:Time Factors; D014908:Triticum; D014587:Ustilaginales / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism* / Q000502:physiology
D006017:Glycolipids; D026901:Membrane Transport Proteins; D010969:Plastics; C439671:mannosylerythritol lipid; D005964:Glucosyltransferases