Endophytic yeasts of genus Rhodotorula are gaining importance for their ability to improve plant growth. The nature of their interaction with plants, however, remains unknown. Rhodotorula mucilaginosa JGTA-S1 was isolated as an endophyte of Typha angustifolia and promoted growth in the host. To investigate the life-strategy of the yeast from a genomics perspective, we used Illumina and Oxford Nanopore reads to generate a high-quality annotated draft assembly of JGTA-S1 and compared its genome to three other Rhodotorula yeasts and the close relative Rhodosporidium toruloides. JGTA-S1 is a haploid yeast possessing several genes potentially facilitating its endophytic lifestyle such as those responsible for solubilizing phosphate and producing phytohormones. An intact mating-locus in JGTA-S1 raised the possibility of a yet unknown sexual reproductive cycle in Rhodotorula yeasts. Additionally, JGTA-S1 had functional anti-freezing genes and was also unique in lacking a functional nitrate-assimilation pathway-a feature that is associated with obligate biotrophs. Nitrogen-fixing endobacteria were found within JGTA-S1 that may circumvent this defective N-metabolism. JGTA-S1 genome data coupled with experimental evidence give us an insight into the nature of its beneficial interaction with plants.

中文翻译：

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内生酵母粘菌Rhodotorula mucilaginosa JGTA-S1-独特的生命策略-比较基因组学观点。

红景天属的内生酵母因其改善植物生长的能力而变得越来越重要。然而，它们与植物相互作用的性质仍然未知。分离到的Rhodotorula mucilaginosa JGTA-S1是香蒲的内生菌，并促进了宿主的生长。为了从基因组学的角度研究酵母的生命策略，我们使用了Illumina和Oxford Nanopore读数来生成高质量的带注释的JGTA-S1草稿集，并将其基因组与其他三种Rhodotorula酵母和近亲Rhodosporidium toruloides进行了比较。JGTA-S1是一种单倍体酵母，具有几个可能促进其内生生活方式的基因，例如负责溶解磷酸盐和产生植物激素的基因。JGTA-S1中完整的交配位点增加了红假单胞菌酵母中未知的有性生殖周期的可能性。此外，JGTA-S1具有抗冻功能基因，并且在缺乏功能性硝酸盐同化途径方面也独树一帜，这是与专性生物营养相关的特征。在JGTA-S1中发现了固氮内细菌，它可以避免这种有缺陷的N代谢。JGTA-S1基因组数据与实验证据相结合，使我们能够深入了解其与植物相互作用的本质。