Comparative Glucose and Xylose Coutilization Efficiencies of Soil-Isolated Yeast Strains Identify Cutaneotrichosporon dermatis as a Potential Producer of Lipid

Abstract

Glucose and xylose are the major hydrolysates of lignocellulose, and therefore, it is of great implication to identify the microbes involved in simultaneous utilization of glucose and xylose. In this study, the strain ZZ-46 isolated from the soil of Nanyang, China, could simultaneously assimilate glucose and xylose efficiently to produce lipid. Upon cultivation with a 2:1 glucose/xylose mixture as the carbon source for 144 h, the cell biomass, lipid concentration, lipid content, and lipid yield of ZZ-46 reached 19.85 ± 0.39 g/L, 9.53 ± 0.60 g/L, 48.05 ± 3.51%, and 0.142 ± 0.003 g/g sugar, respectively. Moreover, C16 and C18 fatty acids were the main constituents of lipid produced by ZZ-46. In addition, ZZ-46 was identified as Cutaneotrichosporon dermatis by the morphology features and phylogenetic analyses. The strain ZZ-46 would have good perspective in practical application for converting lignocellulose into microbial lipid.

Draft Genome Assembly and Annotation for Cutaneotrichosporon dermatis NICC30027, an Oleaginous Yeast Capable of Simultaneous Glucose and Xylose Assimilation

“…Yet, the modified strains created by these techniques are incapable of efficiently co-utilizing xylose and glucose. The strain C. dermatis NICC30027 demonstrated natural capacity to consume xylose and glucose [ 15 ]. In our opinion, one of the following conditions exists in the strain C. dermatis NICC30027: i) there is a high level of the cAMP-CAP complex in the cell due to some unknown metabolic mechanisms; ii) the expressions of key genes involved in xylose metabolism do not require cAMP-CAP mediated activation.…”

“…The NICC30027 strain was cultured in YPD medium (glucose 20 g/L, yeast extract 10 g/L, and peptone 10 g/L) at 30°C with constant shaking (180 rpm) [ 15 ]. Cultures were established by inoculating a single colony in 10 mL of YPD medium in a 50 mL flask and culturing the cells overnight, followed by the transfer of 1 mL of this solution to 100 mL of YPD medium in a 500 mL flask.…”

“…In a prior investigation, our team obtained a yeast strain capable of producing lipids from the soil in Nanyang, China. This strain was identified as Cutaneotrichosporon dermatis using morphological and phylogenetic analysis and is now housed in the Nanyang Center of Industrial Culture Collection (NICC, Henan Province, China; S.No: NICC30027) [ 15 ]. Regardless of the glucose/xylose ratios, strain NICC30027 could efficiently absorb glucose and xylose simultaneously to accumulate a significant quantity of lipid when mixed sugars were employed as the carbon source.…”

“…Regardless of the glucose/xylose ratios, strain NICC30027 could efficiently absorb glucose and xylose simultaneously to accumulate a significant quantity of lipid when mixed sugars were employed as the carbon source. The biomass and lipid concentrations were maximum when the glucose/xylose ratio was 2:1, attaining 19.85 ± 0.39 and 9.53 ± 0.60 g/L, respectively [ 15 ]. Additionally, strain NICC30027 largely produced fatty acids in the C16 and C18 series with content comparable to that of vegetable oil, suggesting that this microorganism may be well suited for use in biodiesel production [ 15 ].…”

“…The biomass and lipid concentrations were maximum when the glucose/xylose ratio was 2:1, attaining 19.85 ± 0.39 and 9.53 ± 0.60 g/L, respectively [ 15 ]. Additionally, strain NICC30027 largely produced fatty acids in the C16 and C18 series with content comparable to that of vegetable oil, suggesting that this microorganism may be well suited for use in biodiesel production [ 15 ].…”