Bank S, Yan B, Miller T L
Department of Chemistry, State University of New York at Albany 12222, USA.
Solid State Nucl Magn Reson. 1996 Dec;7(3):253-61. doi: 10.1016/s0926-2040(96)01261-1.
Whole cells of Methanosphaera stadtmanae were grown in media containing [13C]CO2, [2-13C]acetate, [1-13C]acetate, [3-13C]serine and [1-13C]formate. The label incorporation was determined using solid state 13C CPMAS NMR spectroscopy. The incorporation of serine hydroxymethyl carbon into the purine rings of nucleic acids and most probably the methyl group of thymine is demonstrated. The one carbon atom pathway shown in our previous work is operative in the biosynthesis of purines and pyrimidines. In addition, these studies clearly identified signals not observed in solution NMR spectroscopy and revealed an important pathway not previously known. The reversibility of formyl-containing one carbon atom carriers is demonstrated. The pattern of labeled carbon atoms in sugars confirms the biosynthetic route from pyruvate, which is formed from acetic acid and carbon dioxide. Finally, a preliminary lipid assignment is indicated. The solid state 13C CPMAS NMR of these intact cells proved to be a facile method to follow specific pathways.
将史氏甲烷球形菌的全细胞在含有[¹³C]CO₂、[2-¹³C]乙酸盐、[1-¹³C]乙酸盐、[3-¹³C]丝氨酸和[1-¹³C]甲酸的培养基中培养。使用固态¹³C交叉极化/魔角旋转核磁共振光谱法测定标记掺入情况。结果表明丝氨酸羟甲基碳掺入到核酸的嘌呤环中，很可能还掺入到胸腺嘧啶的甲基中。我们之前工作中展示的一碳途径在嘌呤和嘧啶的生物合成中起作用。此外，这些研究清楚地识别出了在溶液核磁共振光谱中未观察到的信号，并揭示了一条以前未知的重要途径。证明了含甲酰基的一碳载体的可逆性。糖类中标记碳原子的模式证实了由乙酸和二氧化碳形成的丙酮酸的生物合成途径。最后，给出了脂质的初步归属。这些完整细胞的固态¹³C交叉极化/魔角旋转核磁共振证明是一种追踪特定途径的简便方法。
