Cyberlindnera dasilvae sp. nov., a xylitol-producing yeast species isolated from rotting wood and frass of cerambycid larva

Abstract

Six yeast isolates were obtained from rotting wood samples in Brazil and frass of a cerambycid beetle larva in French Guiana. Sequence analysis of the ITS-5.8S region and the D1/D2 domains of the large subunit rRNA gene showed that the isolates represent a novel species of Cyberlindnera. This novel species is related to Cyberlindnera japonica, Cyberlindnera xylosilytica, Candida easanensis and Candida maesa. It is heterothallic and produces asci with two or four hat-shaped ascospores. The name Cyberlindnera dasilvae sp. nov. is proposed to accommodate the novel species. The holotype of Cy. dasilvae is CBS 16129T and the designated paratype is CBS 16584. The MycoBank number is 838252. All isolates of Cy. dasilvae were able to convert xylose into xylitol with maximum xylitol production within 60 and 72 h. The isolates produced xylitol with values ranging from 12.61 to 31.79 g l−1 in yeast extract–peptone–xylose medium with 5% xylose. When the isolates were tested in sugarcane bagasse hydrolysate containing around 35–38 g l−1 d-xylose, isolate UFMG-CM-Y519 showed maximum xylitol production.

The Brazilian Amazonian rainforest harbors a high diversity of yeasts associated with rotting wood, including many candidates for new yeast species

“…shehatae (both present in our samples), and some members of the genus Spathaspora are considered prominent species for the conversion of xylose to ethanol (Cadete & Rosa, 2018; Cadete et al, 2015; Morais et al, 2020). Among other species we reported here, C. tropicalis , C. intermedia , C. maltosa , and species of the genera Cyberlindnera , Sugiyamaella , Wickerhamomyces , Meyerozyma , and Pichia were also reported to ferment xylose into ethanol and/or xylitol (Barros et al, 2021; Bazoti et al, 2017; Geijer et al, 2020; Morais et al, 2020; Narisetty et al, 2021; Sena et al, 2017).…”

“…Similarly, C. albicans is known as a human commensal and opportunistic pathogen, but it is sporadically found on plant materials (Bensasson et al, 2019; Lachance et al, 1923; Opulente et al, 2019). Cyberlindnera species are frequently recovered from this type of substrate (Barros et al, 2021; Boontham et al, 2017). In this study, we found two new species belonging to this clade.…”

“…Some possible new species isolated in this work were placed in clades reported to harbor species that can convert xylose into products of great economic interest (Morais et al, 2020). Among the major clades of yeasts associated with rotting wood habitats, five are worth mentioning for their ability to assimilate/ferment lignocellulose‐related sugars and/or to produce enzymes that act on this substrate: Spathaspora , Scheffersomyces , Spencermartinsiella , Sugiyamaella , and Cyberlindnera (Barros et al, 2021; Cadete et al, 2017).…”

“…Spathaspora, Scheffersomyces, Spencermartinsiella, Sugiyamaella, and Cyberlindnera (Barros et al, 2021;Cadete et al, 2017).…”

“…Starmerella species are prevalent in stingless bees in Brazilian savannas, and Torulaspora delbrueckii was also frequently isolated from those insects (Januário da Costa Neto & Benevides de Morais, 2020). Finally, the guts of wood‐feeding insects are rich in ascomycete yeasts, in particular xylose‐fermenting and xylose‐assimilating yeasts, which are commonly present in the guts, frass, and larvae of beetles of Passalidae and Cerambycidae families (Barros et al, 2021; Nguyen et al, 2006; Souza et al, 2017; Urbina et al, 2013).…”