金属离子对面包酵母合成ATP的影响机制初探

对Mg2+, K+和Na+在面包酵母酶系合成ATP过程中的影响机制进行了初步研究. 发现Mg2+对ATP的合成影响很大，当Mg2+浓度为40 mmol/L时，ATP合成量达到最大值，为6.07 mmol/L；高浓度磷酸钾缓冲液会抑制ATP的合成，进一步研究发现高浓度K+对ATP合成具有明显抑制作用，但K+完全缺乏时，也不利于腺苷的转化；Na+可通过激活腺苷酸激酶的活性来促进ATP合成，同时激活腺苷脱氨酶的活性，其存在会使底物腺苷向肌苷转化.

Influence Mechanism of Metal Ions on ATP Production by the Cells of Saccharomyces cerevisiae

ATP (adenosine 5￠-triphosphate) is very important in all lives as a carrier of energy. It can also be used as an energy supply for some enzymatic reaction systems. In this report the cells of Saccharomyces cerevisiae WSH-J701were used for the enzymatic production of ATP from glucose and adenosine. The influences of Mg2+, K+ and Na+ on ATP production were investigated. The results showed that Mg2+ greatly affected the synthesis of ATP. The highest ATP production (6.07 mmol/L) could be achieved at Mg2+ concentration of 40 mmol/L. High concentration of potassium phosphate buffer was not favorable for ATP production. At high levels of K+ concentration, ATP production was obviously inhibited, whereas adenosine could not be completely consumed in the absence of K+. Na+ promoted ATP production by stimulating the activity of adenylate kinase. In the meantime, the presence of Na+ resulted in the conversion of adenosine to inosine by stimulating the activity of adenine dehydrated ammonia enzyme.