摘要: | 煙醯胺單核苷酸(Nicotinamide Mononucleotide, NMN)是由 D-核糖使用三種酶合成 的關鍵產物,其中5-磷酸核糖-1-焦磷酸(Phosphoribosyl pyrophosphate, PRPP)合成酶起著 至關重要的作用。PRPP合成酶催化磷酸核糖基焦磷酸(PRPP)的形成,PRPP是NMN生 物合成的關鍵前體。本研究的重點是優化PRPP合成酶以提高NMN生產效率。簡要介 紹了PRPP合成酶,強調了PRPP在細胞代謝中的重要性及其在NMN生物合成中的作 用。優化過程涉及研究各種參數,例如溫度、pH值、受質濃度和金屬輔助因子可用性。 通過系統地優化這些條件,可以改善 D-核糖向 NMN 的酵素合成,從而為通過酶促途 徑增強NMN的產生。 此外,本研究探討了用於NMN生產的一鍋合成方法,利用 D-核糖作為初始受質,, 並用三種酶的組合催化反應:核糖激酶 (Ribokinase, RBSK)、磷酸核糖焦磷酸合成酶 (Phosphoribosyl Pyrophosphate Synthetase, PRPPS)、煙酰胺磷酸核糖轉移酶 (Nicotinamide Phosphoribosyltransferase, NAMPT)。專門研究了該合成系統中 PRPP 合成酶的優化及其 酶動力學。通過系統地優化反應條件和酶濃度,最大限度地提高D-核糖向NMN的轉化 效率。 總結來說,本研究確認了使用一鍋法生成NMN,,並優化了最金金屬子子濃度為10 mM,使轉化率達到75%。最後,使用8 mM的鎂子子與2 mM的鈷子子搭配,成功將 轉化率提升至88%。;Nicotinamide Mononucleotide (NMN) is a key product synthesized from D-ribose using three enzymes, with Phosphoribosyl Pyrophosphate (PRPP) Synthetase playing a crucial role. PRPP Synthetase catalyzes the formation of PRPP, which is a critical precursor in the biosynthesis of NMN. This study focuses on optimizing PRPP Synthetase to improve NMN production efficiency. A brief introduction of PRPP Synthetase highlights its importance in cellular metabolism and its role in NMN biosynthesis. The optimization process involves studying various parameters such as temperature, pH, substrate concentration, and the availability of metal cofactors. By systematically optimizing these conditions, the enzymatic synthesis of NMN from D-ribose can be enhanced, thereby improving NMN production through enzymatic pathways. Additionally, this study explores a one-pot synthesis method for NMN production using D-ribose as the initial substrate, catalyzed by a combination of three enzymes: Ribokinase (RBSK), Phosphoribosyl Pyrophosphate Synthetase (PRPPS), and Nicotinamide Phosphoribosyltransferase (NAMPT). The research specifically focuses on optimizing PRPP Synthetase within this synthesis system and its enzyme kinetics. By systematically optimizing the reaction conditions and enzyme concentrations, the conversion efficiency of D-ribose to NMN can be maximized. II In summary, this study confirms the use of a one-pot method to produce NMN and optimizes the best metal ion concentration to 10 mM, achieving a conversion rate of 75%. Finally, by using a combination of 8 mM magnesium ions and 2 mM cobalt ions, the conversion rate was successfully increased to 88%. |