Seely R J, Fahrney D E
J Bacteriol. 1984 Oct;160(1):50-4. doi: 10.1128/jb.160.1.50-54.1984.
Batch-grown Methanobacterium thermoautotrophicum cells grew nonexponentially in the absence of exogenous Pi until intracellular cyclic-2,3-diphosphoglycerate (cyclic DPG) had fallen below 2 mumol/g (dry weight), the limit of detection. Growth resumed immediately upon transfer to medium containing Pi Cyclic DPG levels were also below detection in Pi-limited chemostat cultures operating at a dilution rate of 0.173 h-1 (4-h doubling time), with reservoir Pi concentrations below 200 microM. At this dilution rate, the Pi concentration in the culture was 4 microM. An H2-limited steady state was achieved with 400 microM Pi in the inflowing medium (67 microM in the culture). The cyclic DPG content of these cells was 72 to 74 mumol/g, about one-third the amount in batch-grown cells. The specific growth rate accelerated immediately to 0.36 h-1 (1.9-h doubling time) under washout conditions at high dilution rate. The cellular content of cyclic DPG declined over a 2-h period, and then increased rapidly as the Pi level in the medium approached 200 microM. Expansion of the cyclic DPG pool coincided with a marked increase in Pi assimilation. These results indicated that M. thermoautotrophicum accumulated cyclic DPG only when Pi and H2 were readily available.
分批培养的嗜热自养甲烷杆菌细胞在没有外源磷酸根离子（Pi）的情况下呈非指数生长，直到细胞内环状2,3 -二磷酸甘油酸（环状DPG）降至2 μmol/g（干重）以下，即检测限以下。转移到含Pi的培养基后，生长立即恢复。在稀释率为0.173 h⁻¹（4小时倍增时间）且储液罐中Pi浓度低于200 μM的Pi限制恒化器培养物中，环状DPG水平也低于检测限。在此稀释率下，培养物中的Pi浓度为4 μM。在流入培养基中含400 μM Pi（培养物中为67 μM）时达到H₂限制稳态。这些细胞的环状DPG含量为72至74 μmol/g，约为分批培养细胞中含量的三分之一。在高稀释率的冲洗条件下，比生长速率立即加速至0.36 h⁻¹（1.9小时倍增时间）。环状DPG的细胞含量在2小时内下降，然后随着培养基中Pi水平接近200 μM而迅速增加。环状DPG池的扩大与Pi同化的显著增加同时发生。这些结果表明，嗜热自养甲烷杆菌仅在Pi和H₂容易获得时才积累环状DPG。
