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CoQ10具有呼吸链电子传递者、抗氧化性、调控基因表达等多种生理生化功能,目前不仅用作药物也用作食品添加剂。微生物发酵法是当前生产CoQ10的主要方法。在细菌中,芳香族氨基酸和CoQ10的苯核环都是通过莽草酸途径合成;它们在生物体中各自的合成存在着相互调控作用。本试验通过在培养过程中添加芳香族氨基酸来考察了其对沼泽红假单胞菌J001合成CoQ10的影响。结果表明:当色氨酸添加量≥15 mg/L时对CoQ10的合成具有强列的抑制作用;苯丙氨酸添加量≥50 mg/L时对CoQ10的合成具有一定的抑制作用但当添加量≥75 mg/L后对CoQ10的合成变为一定的促进作用;酪氨酸添加量为75~175 mg/L时对CoQ10的合成具有一定的促进作用,但当添加量≥200 mg/L后对CoQ10的合成变为一定的抑制作用。当添加苯丙氨酸100 mg/L+酪氨酸150 mg/L时,CoQ10含量达最高(25.6±1.3 mg CoQ10/g干细胞),比不添加对照提高52.2%。以上结果说明:该菌株CoQ10的合成受到3种芳香族氨基酸的调控,3-脱氧-D-阿拉伯己酮糖-7-磷酸合成酶是同工酶系统并主要受色氨酸调控,无色氨酸培养基及在培养期间添加适量的苯丙氨酸与酪氨酸对该菌株合成CoQ10有利。
CoQ10 has respiratory chain electron transfer, antioxidant, gene expression and other physiological and biochemical functions, is currently used not only as a drug but also as a food additive. Microbial fermentation is currently the main method of producing CoQ10. In bacteria, both the aromatic amino acids and the benzene nucleus of CoQ10 are synthesized by the shikimate pathway; their mutual regulation exists in the individual organisms. In this study, we investigated the effect of Rhodopseudomonas palustris J001 on the synthesis of CoQ10 by adding aromatic amino acids during the culture. The results showed that when the content of tryptophan was more than 15 mg / L, the inhibition of CoQ10 synthesis was inhibited strongly. When the amount of phenylalanine≥50 mg / L, the synthesis of CoQ10 was restrained. However, The amount of 75 mg / L or 75 mg / L could promote the synthesis of CoQ10. When the dosage of tyrosine was 75-175 mg / L, it could promote the synthesis of CoQ10. However, when the dosage was ≥200 mg / L After the synthesis of CoQ10 becomes a certain inhibition. When the concentration of phenylalanine 100 mg / L + tyrosine 150 mg / L was added, the content of CoQ10 was the highest (25.6 ± 1.3 mg CoQ10 / g stem cells), which was 52.2% higher than that of control. The above results indicate that the synthesis of CoQ10 is regulated by three kinds of aromatic amino acids. The 3-deoxy-D-arabinofuranosyl-7-phosphate synthase is an isoenzyme system and is mainly regulated by tryptophan. Acid medium and the addition of proper amount of phenylalanine and tyrosine during the cultivation of this strain of CoQ10 synthesis favorable.