Enlightening Energy Parasitism by Analysis of an ATP/ADP Transporter from Chlamydiae

• DOI: 10.1371/journal.pbio.0050231
• Publication Date: 2007-08-23T11:57:55Z
• Authors: Oliver Trentmann; Matthias Horn; Anke C. Terwissch...; H. Ekkehard Neuhaus; Ilka Haferkamp
• Keywords: Chlamydiae; Transport protein

Energy parasitism by ATP/ADP transport proteins is an essential, common feature of intracellular bacteria such as chlamydiae and rickettsiae, which are major pathogens humans. Although several have so far been characterized, some fundamental questions regarding their function remained unaddressed. In this study, we focused on the detailed biochemical analysis a representative transporter (PamNTT1), from amoeba symbiont Protochlamydia amoebophila (UWE25) to further clarify principle energy exploitation. We succeeded in purification first bacterial nucleotide (NTT) its functional reconstitution into artificial lipid vesicles. Reconstituted PamNTT1 revealed high import velocities for ATP unexpected previously unobserved stimulating effect luminal ADP affinities. Latter preference hetero-exchange independent membrane potential, therefore, not only structurally but also functionally differs well-characterized mitochondrial ADP/ATP carriers. exhibits bidirectional orientation vesicles, interestingly, carriers inserted with N-terminus directed proteoliposomal interior functional. The data presented here comprehensively explain basis how P. manages exploit pool host cell effectively using PamNTT1. This protein mediates preferred ATP, additionally stimulated internal (bacterial) ratio, orientation-dependent functionality ensures that it working mode detrimental amoebophila. Heterologous expression amounts provides crystallization structure/function analyses. Furthermore, essential chlamydial paves way high-throughput uptake studies order screen specific inhibitors potentially suitable anti-chlamydial drugs.