Department of Chemical and Biomolecular Engineering, Clemson University, 206 S. Palmetto Blvd., Clemson, SC, 29634, USA.
Microb Cell Fact. 2017 Nov 17;16(1):206. doi: 10.1186/s12934-017-0820-8.
The oleaginous yeast, Trichosporon oleaginosus, has been extensively studied for its ability to metabolize non-conventional feedstocks. These include phenol-containing waste streams, such as distillery wastewater, or streams consisting of non-conventional sugars, such as hydrolyzed biomass and various bagasse. An initial BLAST search suggests this yeast has putative aromatic metabolizing genes. Given the desirability to valorize underutilized feedstocks such as lignin, we investigated the ability of T. oleaginosus to tolerate and metabolize lignin-derived aromatic compounds.
Trichosporon oleaginosus can tolerate and metabolize model lignin monoaromatics and associated intermediates within funneling pathways. Growth rates and biomass yield were similar to glucose when grown in 4-hydroxybenzoic acid (pHBA) and resorcinol, but had an increased lag phase when grown in phenol. Oleaginous behavior was observed using resorcinol as a sole carbon source. Fed-batch feeding resulted in lipid accumulation of 69.5% on a dry weight basis.
Though the exact pathway of aromatic metabolism remains to be determined for T. oleaginosus, the results presented in this work motivate use of this organism for lignin valorization and phenolic wastewater bioremediation. Trichosporon oleaginosus is the first yeast shown to be oleaginous while growing on aromatic substrates, and shows great promise as a model industrial microbe for biochemical and biofuel production from depolymerized lignin.
产油酵母（Trichosporon oleaginosus）因其能够代谢非常规饲料而被广泛研究。这些非常规饲料包括含有苯酚的废水流，如酿酒厂废水，或由非常规糖组成的流，如水解生物质和各种甘蔗渣。初步的 BLAST 搜索表明，这种酵母具有潜在的芳香族代谢基因。考虑到利用未充分利用的饲料（如木质素）的可取性，我们研究了 T. oleaginosus 耐受和代谢木质素衍生芳香族化合物的能力。
产油酵母能够耐受和代谢模型木质素单芳烃和相关的漏斗途径中的中间产物。在 4-羟基苯甲酸（pHBA）和间苯二酚中生长时，其生长速率和生物量产量与葡萄糖相似，但在苯酚中生长时，其生长延迟期增加。在单独使用间苯二酚作为碳源时观察到油脂生成行为。补料分批进料导致基于干重的脂质积累达到 69.5%。
尽管 T. oleaginosus 的芳香族代谢途径仍有待确定，但本工作中的结果为利用该生物体进行木质素增值和酚类废水生物修复提供了动力。产油酵母是第一个在芳香族底物上生长时具有油脂生成能力的酵母，并且作为从解聚木质素生产生化和生物燃料的模型工业微生物具有很大的潜力。
