Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, CO 80303, USA.
Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, 80045, USA.
Chembiochem. 2024 Jan 15;25(2):e202300572. doi: 10.1002/cbic.202300572. Epub 2023 Nov 29.
Biomanufacturing via microorganisms relies on carbon substrates for molecular feedstocks and a source of energy to carry out enzymatic reactions. This creates metabolic bottlenecks and lowers the efficiency for substrate conversion. Nanoparticle biohybridization with proteins and whole cell surfaces can bypass the need for redox cofactor regeneration for improved secondary metabolite production in a non-specific manner. Here we propose using nanobiohybrid organisms (Nanorgs), intracellular protein-nanoparticle hybrids formed through the spontaneous coupling of core-shell quantum dots (QDs) with histidine-tagged enzymes in non-photosynthetic bacteria, for light-mediated control of bacterial metabolism. This proved to eliminate metabolic constrictions and replace glucose with light as the source of energy in Escherichia coli, with an increase in growth by 1.7-fold in 75 % reduced nutrient media. Metabolomic tracking through carbon isotope labeling confirmed flux shunting through targeted pathways, with accumulation of metabolites downstream of respective targets. Finally, application of Nanorgs with the Ehrlich pathway improved isobutanol titers/yield by 3.9-fold in 75 % less sugar from E. coli strains with no genetic alterations. These results demonstrate the promise of Nanorgs for metabolic engineering and low-cost biomanufacturing.
生物制造依赖于微生物的碳底物作为分子原料，并提供能量来进行酶反应。这会造成代谢瓶颈，降低底物转化效率。通过纳米粒子与蛋白质和整个细胞表面的生物杂交，可以绕过对氧化还原辅因子再生的需求，从而以非特异性方式提高次生代谢产物的产量。在这里，我们提出使用纳米生物杂交体（Nanorgs），即在非光合细菌中通过核心-壳量子点（QD）与组氨酸标记酶的自发偶联形成的细胞内蛋白质-纳米粒子杂种，用于用光来控制细菌代谢。这证明可以消除代谢限制，并以光代替葡萄糖作为大肠杆菌的能源，在营养物质减少 75%的培养基中，其生长速度提高了 1.7 倍。通过碳同位素标记进行代谢组学追踪证实了通过靶向途径的通量分流，相应目标下游的代谢物积累。最后，在没有遗传改变的大肠杆菌菌株中，应用带有 Ehrlich 途径的 Nanorgs 将糖用量减少 75%，同时将异丁醇的产量提高了 3.9 倍。这些结果表明，Nanorgs 在代谢工程和低成本生物制造方面具有广阔的应用前景。
