Navon G, Shulman R G, Yamane T, Eccleshall T R, Lam K B, Baronofsky J J, Marmur J
Biochemistry. 1979 Oct 16;18(21):4487-99. doi: 10.1021/bi00588a006.
High-resolution phosphorus-31 nuclear magnetic resonance (31P NMR) spectra of wild-type and mutant strains of Saccharomyces cerevisiae were observed at a frequency of 145.7 MHz. Levels of various phosphorus metabolites were investigated upon addition of glucose under both aerobic and anaerobic conditions. Three mutant strains were isolated and their biochemical defects characterized: pfk lacked phosphofructokinase activity; pgi lacked phosphoglucose isomerase activity; and cif had no glucose catabolite repression of the fructose bisphosphatase activity. Each mutant strain was found to accumulate characteristic sugar phosphates when glucose was added to the cell suspension. In the case of the phosphofructokinase deficient mutant, the appearance of a pentose shunt metabolite was observed. 31P NMR peak assignments were made by a pH titration of the acid extract of the cells. Separate signals for terminal, penultimate, and central phosphorus atoms in intracellular polyphosphates allowed the estimation of their average molecular weight. Signals for glycero(3)phosphochline, glycero(3)phosphoserine, and glycero(3) phosphoethanolamine as well as three types of nucleotide diphosphate sugars could be observed. The intracellular pH in resting and anaerobic cells was in the range 6.5--6.8 and the level of adenosine 5'-triphosphate (ATP) low. Upon introduction of oxygen, the ATP level increased considerably and the intracellular pH reached a value of pH 7.2--7.3, irrespective of the external medium pH, indicating active proton transport in these cells. A new peak representing the inorganic phosphate of one of the cellular organelles, whose pH differed from the cytoplasmic pH, could be detected under appropriate conditions.
在145.7兆赫兹的频率下观察了酿酒酵母野生型和突变株的高分辨率磷-31核磁共振（31P NMR）光谱。在有氧和无氧条件下添加葡萄糖后，研究了各种磷代谢物的水平。分离出三个突变株并对其生化缺陷进行了表征：pfk缺乏磷酸果糖激酶活性；pgi缺乏磷酸葡萄糖异构酶活性；cif对果糖双磷酸酶活性没有葡萄糖分解代谢抑制作用。当向细胞悬液中添加葡萄糖时，发现每个突变株都会积累特征性的糖磷酸盐。在磷酸果糖激酶缺陷型突变体的情况下，观察到了戊糖支路代谢物的出现。通过对细胞酸提取物进行pH滴定来确定31P NMR峰的归属。细胞内多磷酸盐中末端、倒数第二个和中心磷原子的单独信号使得能够估计它们的平均分子量。可以观察到甘油（3）磷酸胆碱、甘油（3）磷酸丝氨酸和甘油（3）磷酸乙醇胺以及三种类型的核苷酸二磷酸糖的信号。静止和厌氧细胞的细胞内pH值在6.5 - 6.8范围内，腺苷5'-三磷酸（ATP）水平较低。引入氧气后，无论外部培养基的pH值如何，ATP水平都会显著增加，细胞内pH值达到7.2 - 7.3，表明这些细胞中有活跃的质子转运。在适当条件下，可以检测到代表一种细胞器无机磷酸盐的新峰，其pH值与细胞质pH值不同。
