Graven Patricia, Tambalo Margherita, Scapozza Leonardo, Perozzo Remo
Pharmaceutical Biochemistry Group, School of Pharmaceutical Sciences, University of Lausanne & University of Geneva, Quai Ernest-Ansermet 30, 1211 Geneva 4, Switzerland.
Pharmaceutical Biochemistry Group, School of Pharmaceutical Sciences, University of Lausanne & University of Geneva, Quai Ernest-Ansermet 30, 1211 Geneva 4, Switzerland.
Exp Parasitol. 2014 Jun;141:28-38. doi: 10.1016/j.exppara.2014.03.006. Epub 2014 Mar 19.
Human African Trypanosomiasis (HAT) is caused by the protozoan parasite Trypanosoma brucei. Although trypanosomes are well-studied model organisms, only little is known about their adenine and guanine nucleotide pools. Besides being building blocks of RNA and DNA, these nucleotides are also important modulators of diverse biochemical cellular processes. Adenine nucleotides also play an important role in the regulation of metabolic energy. The energetic state of cells is evaluated by the energy charge which gives information about how much energy is available in form of high energy phosphate bonds of adenine nucleotides. A sensitive and reproducible ion-pair RP-HPLC/UV method was developed and optimized, allowing the quantification of guanine and adenine nucleosides/nucleotides in T. brucei. With this method, the purine levels and their respective ratios were investigated in trypanosomes during logarithmic, stationary and senescent growth phases. Results of this study showed that all adenine and guanine purines under investigation were in the low mM range. The energy charge was found to decrease from logarithmic to static and to senescent phase whereas AMP/ATP, ADP/ATP and GDP/GTP ratios increased in the same order. In addition, the AMP/ATP ratio varied as the square of the ADP/ATP ratio, indicating AMP to be the key energy sensor molecule in trypanosomes.
人类非洲锥虫病（HAT）由原生动物寄生虫布氏锥虫引起。尽管锥虫是经过充分研究的模式生物，但人们对其腺嘌呤和鸟嘌呤核苷酸库却知之甚少。除了作为RNA和DNA的组成成分外，这些核苷酸还是多种生化细胞过程的重要调节因子。腺嘌呤核苷酸在代谢能量调节中也起着重要作用。细胞的能量状态通过能量电荷来评估，能量电荷提供了有关腺嘌呤核苷酸高能磷酸键形式的可用能量的信息。我们开发并优化了一种灵敏且可重复的离子对反相高效液相色谱/紫外检测法，用于定量布氏锥虫中的鸟嘌呤和腺嘌呤核苷/核苷酸。利用该方法，研究了锥虫在对数生长期、稳定期和衰老期的嘌呤水平及其各自的比例。本研究结果表明，所有被研究的腺嘌呤和鸟嘌呤嘌呤均处于低毫摩尔范围内。发现能量电荷从对数期到静止期再到衰老期逐渐降低，而AMP/ATP、ADP/ATP和GDP/GTP的比例则按相同顺序增加。此外，AMP/ATP比例随ADP/ATP比例的平方变化，表明AMP是锥虫中的关键能量传感分子。
