Aliyu Habibu, Gorte Olga, Neumann Anke, Ochsenreither Katrin
Institute of Process Engineering in Life Science 2: Technical Biology, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.
J Fungi (Basel). 2021 Sep 15;7(9):758. doi: 10.3390/jof7090758.
Unlike conventional yeasts, several oleaginous yeasts, including DSM 27192, possess the innate ability to grow and produce biochemicals from plant-derived lignocellulosic components such as hexose and pentose sugars. To elucidate the genetic basis of growth and lipid production on glucose and xylose, we performed comparative temporal transcriptome analysis using RNA-seq method. Approximately 3.4 and 22.2% of the 10,670 expressed genes were differentially (FDR < 0.05, and log2FC > 1.5) expressed under batch and fed batch modes, respectively. Our analysis revealed that a higher number of sugar transporter genes were significantly overrepresented in xylose relative to glucose-grown cultures. Given the low homology between proteins encoded by most of these genes and those of the well-characterised transporters, it is plausible to conclude that possesses a cache of putatively novel sugar transporters. The analysis also suggests that potentially channels carbon flux from xylose via both the non-oxidative pentose phosphate and potentially via the first steps of the Weimberg pathways to yield xylonic acid. However, only the ATP citrate lyase (ACL) gene showed significant upregulation among the essential oleaginous pathway genes under nitrogen limitation in xylose compared to glucose cultivation. Combined, these findings pave the way toward the design of strategies or the engineering of efficient biomass hydrolysate utilization in for the production of various biochemicals.
与传统酵母不同,包括DSM 27192在内的几种产油酵母具有从植物衍生的木质纤维素成分(如己糖和戊糖)中生长并生产生物化学物质的内在能力。为了阐明在葡萄糖和木糖上生长及脂质生产的遗传基础,我们使用RNA测序方法进行了比较性的时间转录组分析。在10,670个表达基因中,分别约有3.4%和22.2%在分批培养和补料分批培养模式下差异表达(FDR < 0.05,且log2FC > 1.5)。我们的分析表明,相对于以葡萄糖为培养基生长的培养物,在以木糖为培养基生长的培养物中,有更多的糖转运蛋白基因显著富集。鉴于这些基因中大多数编码的蛋白质与那些已充分表征的转运蛋白之间的同源性较低,可以合理地得出结论,DSM 27192拥有一批可能是新型的糖转运蛋白。该分析还表明,DSM 27192可能通过非氧化戊糖磷酸途径以及可能通过魏姆伯格途径的第一步将木糖的碳通量引导至产生木糖酸。然而,与葡萄糖培养相比,在木糖氮限制条件下,只有ATP柠檬酸裂解酶(ACL)基因在必需的产油途径基因中显示出显著上调。综合这些发现,为设计策略或对DSM 27192进行工程改造以有效利用生物质水解产物来生产各种生物化学物质铺平了道路。