Zakharova E V, Rodionov Iu V, Ivanovskiĭ R N
Mikrobiologiia. 1980 Mar-Apr;49(2):215-20.
Whole cells and cell-free preparations of the methylotrophic bacteria, Pseudomonas sp. AM 1 and Achromobacter parvulus, can oxidize formate at tis concentration in the reaction medium up to 1 M. The respiration of whole cells is registered at a concentration of formate greater than 10(-2) M, while that of cell-free extracts at a formate concentration greater than 5 X 10(-5) M. This seems to be due to the presence of a permeability barrier in cells for formate. The oxidation of reduced TMPD and exogenous cytochrome c by the membrane preparations of the two bacteria is inhibited by formate and cyanide; Ki50% = 2.5 X 10(-2) and 10(-6) M, respectively. The oxidation of NADH by the membrane preparations of the bacteria is not inhibited by 1 M formate and 5 X 10(-4) M cyanide but is inhibited by formaldehyde with Ki50% = 3 X 10(-2) M. Formaldehyde has no effect on the oxidation of reduced TMPD and cytochrome c at concentrations greater than 2 X 10(-1) M. These data indicate that respiration of the studied methylotrophic bacteria in the presence of high formate concentrations should be attributed in the presence of a branched electron transport chain in them; one branch of the chain is resistant to formate and cyanide, but is sensitive to formaldehyde.
甲基营养菌假单胞菌属AM 1和微小无色杆菌的全细胞及无细胞制剂，能够在反应介质中高达1 M的甲酸盐浓度下氧化甲酸盐。全细胞的呼吸作用在甲酸盐浓度大于10⁻² M时可检测到，而无细胞提取物的呼吸作用在甲酸盐浓度大于5×10⁻⁵ M时可检测到。这似乎是由于细胞对甲酸盐存在渗透屏障。两种细菌的膜制剂对还原型TMPD和外源细胞色素c的氧化作用受到甲酸盐和氰化物的抑制；50%抑制浓度（Ki50%）分别为2.5×10⁻² M和10⁻⁶ M。细菌膜制剂对NADH的氧化作用不受1 M甲酸盐和5×10⁻⁴ M氰化物的抑制，但受到甲醛的抑制，Ki50% = 3×10⁻² M。甲醛在浓度大于2×10⁻¹ M时对还原型TMPD和细胞色素c的氧化作用没有影响。这些数据表明，所研究的甲基营养菌在高浓度甲酸盐存在下的呼吸作用应归因于它们存在分支电子传递链；该链的一个分支对甲酸盐和氰化物具有抗性，但对甲醛敏感。
