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The following is not an answer to the original question: "Are Gram negative bacteria classified as such because of their negative membrane potential?" but to the questions later in the text. Usually the membrane potential is given for the inner cytosolic part and the extracellular space, for E. Coli it is around -120 mV; see also this article. Due to the ...


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Short answer The distinction between Gram positive (Gram+) and negative bacteria (Gram-) has absolutely nothing to do with membrane potentials; it is all about the Gram staining procedure. Background The Gram staining was named after the Danish bacteriologist Hans Christian Gram, who originally devised it in 1882 (Gram, 1884). Gram staining is a common ...


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Proteins can move around the membrane. The protein does move: the membrane is a liquid crystal and has fluid behaviour. Specifically this is due to the membrane being in a gel-state. This gel state allows phase behaviour which means that the protein is able to move around on the surface by a similar process. This is often referred to as the fluid mosaic ...


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See this paragraph and image from The Cell: A Molecular Approach. 2nd edition.: During passive diffusion, a molecule simply dissolves in the phospholipid bilayer, diffuses across it, and then dissolves in the aqueous solution at the other side of the membrane...Passive diffusion is thus a nonselective process by which any molecule able to dissolve in the ...


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I try to answer your two questions briefly: Ion gradients are dependent on charge, but there exist independent transport mechanisms, extending diffusion. Trans-membrane transport proteins can specifically move only one sort of ions. Also symport or antiport exists, that can depend on gradients of other (e.g. non-charged molecules). In addition, the ...



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