Hatch T P, Al-Hossainy E, Silverman J A
J Bacteriol. 1982 May;150(2):662-70. doi: 10.1128/jb.150.2.662-670.1982.
Isolated reticulate bodies of Chlamydia psittaci were found to transport ATP and ADP by an ATP-ADP exchange mechanism. ATP uptake activity was not detected in elementary bodies. The apparent Km of transport for both ATP and ADP was approximately 5 microM, and the calculated Vmax for both was about 1 nmol of nucleotide transported per min per mg of protein. ADP competitively inhibited ATP transport with a Ki of 4.5 microM. Other nucleotides tested had no effect on the uptake of ATP. A magnesium-dependent, oligomycin-sensitive ATPase (ATP phosphohydrolase, EC 3.6.1.3) was associated with reticulate bodies, and most of the transported ATP was hydrolyzed to ADP, which was exchanged for additional, extracellular nucleotide. Some ADP was hydrolyzed to AMP, which exited the cells slowly. Lysine was transported against the electrochemical gradient by reticulate bodies in the presence of ATP. Oligomycin and carbonyl cyanide p-trifluoromethoxyphenylhydrazone inhibited ATP-dependent lysine transport. Lysine exited reticulate bodies when the reticulate bodies were incubated in the presence of ADP, carbonyl cyanide p-trifluoromethoxyphenylhydrazone, or a reduced concentration of ATP. The results support the concept that chlamydiae are energy parasites which are capable of drawing upon the adenine nucleotides of their hosts, hydrolyzing ATP, and establishing an energized membrane.
发现鹦鹉热衣原体的分离网状体能通过ATP-ADP交换机制转运ATP和ADP。在原体中未检测到ATP摄取活性。ATP和ADP转运的表观Km约为5 microM，计算得出两者的Vmax约为每分钟每毫克蛋白质转运1 nmol核苷酸。ADP竞争性抑制ATP转运，Ki为4.5 microM。测试的其他核苷酸对ATP摄取无影响。一种依赖镁的、对寡霉素敏感的ATP酶（ATP磷酸水解酶，EC 3.6.1.3）与网状体相关，大部分转运的ATP被水解为ADP，后者与额外的细胞外核苷酸进行交换。一些ADP被水解为AMP，其缓慢排出细胞。在ATP存在下，网状体可逆电化学梯度转运赖氨酸。寡霉素和羰基氰对三氟甲氧基苯腙抑制依赖ATP的赖氨酸转运。当网状体在ADP、羰基氰对三氟甲氧基苯腙或降低浓度的ATP存在下孵育时，赖氨酸从网状体中排出。这些结果支持衣原体是能量寄生虫的概念，它们能够利用宿主的腺嘌呤核苷酸，水解ATP，并建立一个有能量的膜。
