Fig 1.
Lifestyles of nematophagous P. lilacinum and the structures of leucinostatins.
(A) Microscopic conidiophores and conidia (c) of P. lilacinum. Scale bar = 10 μm. The soil saprophyte (s) P. lilacinum colonizes plant roots as an endophyte (e), and the parasite (p) can occur in nematode eggs in the egg mass (em) generated after the infection with the plant nematode (n). (B) Chemical structure of leucinostatins A and B.
Fig 2.
Genomic synteny of PLBJ-1 and PLFJ-1.
(A) The syntenic genome sequences of PLBJ-1 and PLFJ-1 were analyzed by BLASTN, with an E-value cutoff of 1e-5. The red semicircle represents the scaffolds of PLBJ-1, while the blue semicircle represents the scaffolds of PLFJ-1. Scaffold lengths of ≥ 100 Kb were used for this analysis, and the threshold of matched blocks was ≥ 1000 bp, which are connected by lines of the same color. (B) An example of a super-scaffold inferred by syntenic analysis.
Table 1.
Genome feature of the three P. lilacinum isolates.
Fig 3.
Phylogenomic relationships and orthologous gene clusters.
(A) Maximum likelihood phylogeny was computed from a concatenated alignment of 855 groups of single-copy orthologues. Bootstrap values are shown beside the nodes. (B) The number of gene clusters shared by P. lilacinum with other major associated ecologies. Gray = P. lilacinum isolates PLBJ-1 and PLFJ-1; blue = nematode egg parasite P. chlamydosporia isolates 123 and 170; pink = nematode parasite H. minnesotensis; and yellow = nematode-trapping fungi A. oligospora and M. haptotylum.
Fig 4.
The boundary of the lcs cluster in P. lilacinum with its homologues in T. ophioglossoides.
(A) Horizontal arrows of the same color represent the orthologous genes. The sequence identity between the homologous genes from two fungi is shown by shaded areas with different colors. TO, T. ophioglossoides; PL, P. lilacinum. The bars indicate boundaries of the lcs cluster predicted by antiSMASH, SMURF, and qRT-PCR. (B) The expression ratio of the genes around lcsA when expression in PLBJ-1 cultured in leucinostatin-inducing medium was compared to expression in non-inducing medium. The ratios for different genes demonstrated an extensive range, so the breakpoint was inserted into the Y axis.
Fig 5.
HPLC profiles (UV 210 nm) of culture extracts from the wild type P. lilacinum strain and mutants when grown in PDB medium.
Leucinostatins A and B were detected in the wild type isolate, while they were abolished in ΔlcsA, ΔlcsC, ΔlcsD and ΔlcsE.
Table 2.
Description of the genes in the leucinostatin biosynthetic cluster.
Fig 6.
The role of leucinostatins in antagonism between P. lilacinum and Phytophthora.
(A) Cocultivation of P. infestans and wild type, ΔlcsA and OE::lcsF P. lilacinum on rye agar medium. (B) Cocultivation of P. capsici and wild type, ΔlcsA and OE::lcsF P. lilacinum on PDA medium.
Fig 7.
A putative biosynthetic pathway for leucinostatin A.