Draft Genome Sequence of a Basidiomycetous Yeast, Ustilago shanxiensis CBS 10075, Which Produces Mannosylerythritol Lipids

The basidiomycetous yeast Ustilago shanxiensis CBS 10075, which was isolated from a wilting leaf in China, produces mannosylerythritol lipid (MEL) biosurfactants. Here, we report the draft genome sequence of U. shanxiensis CBS 10075, which was 21.7 Mbp in size, with a GC content of 52.55%, comprising 65 scaffolds.

Basidiomycetous Yeast, Glaciozyma antarctica, Forming Frost-Columnar Colonies on Frozen Medium

The basidiomycetous yeast, Glaciozyma antarctica, was isolated from various terrestrial materials collected from the Sôya coast, East Antarctica, and formed frost-columnar colonies on agar plates frozen at −1 °C. Thawed colonies were highly viscous, indicating that the yeast produced a large number of extracellular polysaccharides (EPS). G. antarctica was then cultured on frozen media containing red food coloring to observe the dynamics of solutes in unfrozen water; pigments accumulated in frozen yeast colonies, indicating that solutes were concentrated in unfrozen water of yeast colonies. Moreover, the yeast produced a small quantity of ice-binding proteins (IBPs) which inhibited ice crystal growth. Solutes in unfrozen water were considered to accumulate in the pore of frozen colonies. The extracellular IBPs may have held an unfrozen state of medium water after accumulation in the frost-columnar colony.

CONFIRMATION OF ENDOPHYTIC MICROBES CAUSING CONTAMINATION IN WATER SPINACH (Ipomoea aquatica Forssk.) TISSUE CULTURE

Konfirmasi Mikroba Endofit Penyebab Kontaminasi pada Kultur Jaringan Kangkung (Ipomoea aquatica Forssk.) Tanaman kangkung secara alami bersimbiosis dengan mikroba endofit, yang berpotensi menjadi kontaminan pada kultur jaringan kangkung karena berada di dalam jaringan dan sulit dijangkau saat proses sterilisasi eksplan. Tujuan penelitian ini adalah mengonfirmasi mikroba endofit penyebab kontaminasi pada kultur jaringan kangkung ‘Tetraploid’ sehingga dapat menjadi informasi awal untuk metode sterilisasi yang efektif. Sebanyak 14 sampel kontaminan pada media tanam kultur jaringan kangkung diisolasi dan diidentifikasi secara molekuler berdasarkan gen 16S rDNA untuk bakteri, daerah D1/D2 dari gen LSU rRNA untuk khamir, dan daerah ITS dari gen rDNA untuk jamur. Keragaman jenis mikroba yang teridentifikasi dibandingkan dengan keragaman jenis mikroba endofit dari jaringan tanaman kangkung yang ditanam pada media kultur jaringan tidak terkontaminasi mikroba, media kultur jaringan terkontaminasi mikroba, media tanam campuran tanah steril dan tidak steril, serta kangkung yang didapatkan dari pasar. Hasil penelitian ini mengonfirmasi bahwa khamir endofit dari kelompok Ustilaginaceae (basidiomycetous yeast) yang berasal dari jaringan tanaman kangkung sama dengan jenis kontaminan yang mengontaminasi media kultur jaringan kangkung ‘Tetraploid’. Khamir dari kelompok Ustilaginaceae (basidiomycetous yeast) tersebut juga merupakan mikroba paling dominan yang mengontaminasi media tanam kultur jaringan kangkung ‘Tetraploid’. Keywords: Ipomoea aquatica, kultur jaringan, mikroba endofit, morfologi, pohon filogeni Water spinach in nature lives in symbiosis with endophytic microbes, which have the potential to become contaminants in water spinach tissue culture because they are difficult to eliminate during the explant sterilization process. This study aimed to confirm endophytic microbes that cause contamination in the tissue culture of 'Tetraploid' water spinach so that it can provide initial information for an effective sterilization method. Fourteen contaminant samples in water spinach tissue culture media were isolated and identified molecularly based on the 16S rDNA gene for bacteria, the D1/D2 region of the LSU rRNA gene sequences for yeast, and ITS region of the rDNA gene for mold. The diversity of microbial species identified was compared with the diversity of endophytic microbial types from water spinach plant tissue grown on sterile tissue culture media, microbially contaminated tissue culture media, sterile and non-sterile soil mixed planting media, and water spinach obtained from the market. The results confirmed that endophytic yeast from Ustilaginaceae group (basidiomycetous yeast) derived from water spinach plant tissue was the same type of microbe that contaminated the 'Tetraploid' water spinach tissue culture media. The results gave new information that yeast from the Ustilaginaceae (basidiomycetous yeast) group was the most dominant microbe contaminating water spinach ‘Tetraploid’ tissue culture media. This group is endophytic yeast that lives within Ipomoea aquatica tissues.

Yeast the Present and Future Cell Facture

Yeasts are eukaryotic microorganisms that are existing in a wide range of habitats, thanks to their ability to adapt even in extreme locations and conditions. Moreover, the unicellular nature of yeasts makes them better suited for deep liquid substrates or moist and uneven surfaces. Till now, about 1500 species of yeasts are described, and the genus Saccharomyces is the well-studied genus of all the yeasts in terms of physiology and genetics. In this review, we elucidate the role of yeasts as biotechnological tool and their current and potential applications. We also highlighted the features, and industrial application of some marine yeasts. Furthermore, describing rarely basidiomycetous yeast involved in different applications. Contributions of yeasts and their enzymes in food, industrial, and pharmaceuticals fields were also discussed. Finally, employment of yeasts in biotransformation process was show.

Teunia rosae sp. nov. and Teunia rudbeckiae sp. nov. (Cryptococcaceae, Tremellales), two novel basidiomycetous yeast species isolated from flowers

Three yeast strains isolated from three flower samples were identified as representing two novel species of Teunia based on molecular phylogenetic analysis and phenotypic comparisons. Strains 12A8 and 21S4 with pink cream colonies and subglobose to globose cells had identical sequences in the ITS and LSU D1/D2 regions, which differed from strain X54 with cream colonies and ovoid to ellipsoidal cells by 6 nt substitutions (1 %) and 9 nt mismatches (1.5 %) in the D1/D2 domains and ITS region, respectively. They could also be distinguished from each other in assimilation of glucitol and salicin, growth at 28 °C and cell fibrillar appendages under scanning electron microscopy. The three strains differed from known species of Teunia by more than 8 nt (1.3 %) and 30 nt (5 %) in the D1/D2 domains and ITS region, respectively. Therefore, the names Teunia rudbeckiae sp. nov. (Holotype CGMCC 2.5840, Mycobank MB 835892) and Teunia rosae sp. nov. (Holotype CGMCC 2.5830, MycoBank MB 835891) are proposed to accommodate strain X54, and strains 12A8 and 21S4, respectively.