TRANSMEMBRANE ELECTRICAL POTENTIAL AND TRANSMEMBRANE PH GRADIENT IN THE ACIDOPHILE THIOBACILLUS-FERROOXIDANS
TRANSMEMBRANE ELECTRICAL POTENTIAL AND TRANSMEMBRANE PH GRADIENT IN THE ACIDOPHILE THIOBACILLUS-FERROOXIDANS
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DOI：
10.1042/bj1780195
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发表时间：
1979-01-01
影响因子：
4.1
通讯作者：
INGLEDEW, WJ
中科院分区：
文献类型：
--
作者：
COX, JC;NICHOLLS, DG;INGLEDEW, WJ
T.在pH2.0条件下，氧化亚铁酶能够利用O2对Fe 2+的氧化作用作为生长和CO2固定的唯一能量来源。该细菌在1.0-8.0的外部pH范围内保持6.5的细胞内pH，如通过[14 C]乙酸盐和[3 H]甲胺分布测量的。膜电位由脂溶性阳离子二苄基二甲基铵和阴离子SCN-的分布估计。在pH 2.0（生长的pH）下，在Fe 2+氧化期间，跨膜pH梯度为4.5单位，相对膜电位为-10 mV，得到+256 mV的质子电化学梯度。这种梯度是积极维持。
T. ferrooxidans is capable of using the oxidation of Fe2+ by O2 at pH 2.0 as the sole source of energy for growth and CO2 fixation. The bacterium maintains an intracellular pH of 6.5 over a range of external pH from 1.0-8.0, as measured by [14C]acetate and [3H]methylamine distribution. The membrane potential was estimated by the distribution of the lipid-soluble cation dibenzyldimethylammonium and the anion SCN-. At pH 2.0 (the pH of growth) during Fe2+ oxidation the transmembrane pH gradient is 4.5 units with an opposing membrane potential of -10 mV, giving a proton electrochemical gradient of +256 mV. This gradient is actively maintanined.