Copyright 1999.  ASM Digital Image Collection. Terry

Animation of Electron transport in Bacteria

Go to Animation of ATP synthesis in Bacteria

The schematic diagram above illustrates a bacterial cell. The region in the box is magnified in the second image, showing the electron transport system located in the cell membrane. In the animation, watch as NADH transfers H⁺ ions and electrons into the electron transport system.

Key points:

1. Protons are translocated across the cell membrane, from the cytoplasm to the periplasmic space
2. Electrons are transported along the membrane, through a series of protein carriers
3. Oxygen is the terminal electron acceptor, combining with electrons and H⁺ ions to produce water
4. As NADH delivers more H⁺ and electrons into the ETS, the proton gradient increases, with H⁺ building up outside the cell membrane, and OH^- inside the membrane.