摘要
在光滑球拟酵母(Torulopsis glabrata620)生产丙酮酸的过程中,温度对丙酮酸生物合成有着重要的影响。考察了不同发酵温度下基质消耗、细胞生长、丙酮酸合成及能荷水平和氧化-还原度等方面的差异。在恒温发酵中,维持较高的发酵温度可以增强糖耗,促进菌体生长,加速丙酮酸积累,但前期胞内能荷水平较高,菌体消耗较多葡萄糖合成菌体,后续产酸能力不足,导致丙酮酸得率降低;维持较低的发酵温度可以在发酵后期提供稳定的产酸能力,但菌体代谢缓慢,后期胞内NADH/NAD+水平较高,丙酮酸生产强度降低。因此仅仅采取单一的温度控制策略很难达到丙酮酸高产量、高产率和高生产强度的统一。
Temperature plays an important role in pyruvate biosynthesis by Torulopsis glabrata 620. The effects of temperature on the substrate consumption, cell growth, pyruvate biosynthesis and level of energy charge and oxidation-reduction state have been investigated. During the constant temperature fermentation, higher temperature can enhance the rate of glucose consumption, cell growth and pyruvate production. However, it also leads to higher energy charge in the prophase of fermentation, too much consumption of glucose by cell and deficient throughput of pyruvate in the anaphase of fermentation, which brings on decrease of pyruvate yield. Oppositely, maintaining lower temperature during the fermentation can offer constant production capacity of pyruvate in the anaphase of fermentation. But the disadvantages are lower cell growth and higher level of NADH/NAD^＋ in vivo during the anaphase of fermentation, which leads to lower productivity inevitably. Disaccords above-mentioned indicate that the higher production, higher yield and higher productivity cannot be achieved at one time during a constant temperature fermentation.
出处
《生物工程学报》
CAS
CSCD
北大核心
2006年第2期316-321,共6页
Chinese Journal of Biotechnology
关键词
丙酮酸
生物合成
动力学
能荷
氧化-还原度
pyruvate, biosynthesis, kinetics, energy charge, oxidation-reduction state
