MICROBIAL GROWTH ON C1 COMPOUNDS .2. SYNTHESIS OF CELL CONSTITUENTS BY METHANOL- AND FORMATE-GROWN PSEUDOMONAS AM 1, AND METHANOL-GROWN HYPHOMICROBIUM VULGARE
MICROBIAL GROWTH ON C1 COMPOUNDS .2. SYNTHESIS OF CELL CONSTITUENTS BY METHANOL- AND FORMATE-GROWN PSEUDOMONAS AM 1, AND METHANOL-GROWN HYPHOMICROBIUM VULGARE
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DOI：
10.1042/bj0810470
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发表时间：
1961-01-01
影响因子：
4.1
通讯作者：
PEEL, D
中科院分区：
文献类型：
--
作者：
LARGE, PJ;QUAYLE, JR;PEEL, D
已研究了通过在甲醇上生长的假单胞菌 AM 1 和普通丝菌培养物从[ 14 C]甲醇和[ 14 C]碳酸氢盐中掺入C，以及通过在甲酸上生长的假单胞菌AM 1 培养物从[ 14 C]甲酸和[ 14 C]碳酸氢盐中掺入C。孵育长达2分钟后，通过色谱法和放射自显影分析了细胞的乙醇可溶部分的非挥发性成分内的放射性分布。 [14C]甲醇或[14C]甲酸固定的第一个稳定产物是丝氨酸（约占固定总数的50%）和C4二羧酸，例如苹果酸和天冬氨酸。在 H. vulgare 中也观察到放射性乙醇酸盐。放射性磷酸化化合物最早存在于甲醇培养的假单胞菌 AM 1 中，但仅在其他两个培养实验中较晚才出现。放射性甘氨酸在培养早期出现，但其占固定总计数的比例不超过15%，并且始终低于丝氨酸。在培养过程中出现标记的其他化合物包括谷氨酸盐、柠檬酸盐以及假单胞菌 AM 1 中的海藻糖。 [14]碳酸氢盐固定的第一个稳定产物是C4酸、苹果酸和天冬氨酸（它们占固定总计数的40-70%）和甘氨酸。其他被标记的化合物包括丝氨酸、磷酸化化合物、谷氨酸和假单胞菌 AM 1 中的海藻糖。将每种放射性化合物中所含的固定总计数的百分比相对于时间作图。获得的曲线的斜率表明，丝氨酸是[14C]甲醇或[14C]甲酸掺入的主要产物（以及H. vulgare中的乙醇酸），而苹果酸或天冬氨酸是[14C]-碳酸氢盐掺入的主要产物。在空气[14C]甲醇中生长的假单胞菌 AM 1 中获得的细胞材料的比放射性在鼓泡空气[长划线]CO2 (99 1, v/v) 中通过生长培养物降低了 1/2。这表明至少 50% 的 C 掺入必须经过 CO2 或与其处于平衡状态的化合物的阶段。在生物体的无细胞提取物中未发现羧基歧化酶活性。这一事实与其他数据一起表明，涉及二氧化碳固定的核酮糖二磷酸循环的自养代谢无法运行。
A studv has been made of the incorporation of C from [14C]methanol and [14C]bicarbonate by cultures of Pseudomonas AM 1 and Hyphomicrobium vulgare grown on methanol, and from [14C]formate and [14C]bicarbonate by cultures of Pseudomonas AM 1 grown on formate. The distribution of radioactivity within the nonvolatile constituents of the ethanol-soluble fractions of the cells, after incubation for periods up to 2 min., has been analysed by chromatography and radioautography. The first stable products of [14C]methanol or [14C]formate fixation were serine (containing approx. 50% of the total count fixed) and C4 dicarboxylic acids such as malate and aspartate. Radioactive glycollate was also observed in H. vulgare. Radioactive phosphorylated compounds were present at the earliest time in methanol-grown Pseudomonas AM 1, but only appeared at later times in the other two incubation experiments. Radioactive glycine appeared at early times of incubation, but its proportion of the total count fixed did not exceed 15% and was less at all times than that of serine. Other compounds which appeared labelled during the incubations included glutamate, citrate and, in Pseudomonas AM 1, trehalose. The first stable products of [14]bicarbonate fixation were the C4 acids, malate and aspartate (containing between them 40-70% of the total count fixed) and glycine. Other compounds becoming labelled included serine, phosphorylated compounds, glutamate, and, in Pseudomonas AM 1, trehalose. The percentage of the total count fixed which was contained in each of the radioactive compounds was plotted against time. The slopes of the curves obtained show that serine is a primary product of [14C]methanol or [14C]formate incorporation (and glycollate in H. vulgare), and that malate or aspartate is a primary product of [14C]-bicarbonate incorporation. The specific radioactivity of cellular material obtained from Pseudomonas AM 1 grown on [14C]methanol in air reduced by 1/2 on bubblingair[long dash]CO2(99 1, v/v) through the growing culture. This shows that at least 50% of the C incorporated must have passed through the stage of CO2 or a compound in ready equilibrium with it. No carboxydismutase activity has been found in cell-free extracts of the organisms. This fact, together with the other data, shows that an autotrophic metabolism involving the ribulose diphosphate cycle of CO2 fixation cannot be operating.