The SNP mutation responsible for sickle-cell disease changes amino acid 6 in haemoglobin β from glutamic acid (E) to valine (V). 

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#Id: 3338

#Unit 6. System Physiology – Plant

F1 has nine subunits of five different types, with the composition α₃ β₃ ϒδε

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#Id: 3340

#Unit 6. System Physiology – Plant

Each of the three β subunits has one catalytic site for ATP synthesis.

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#Id: 3341

#Unit 6. System Physiology – Plant

Fo complex, with its proton pore, is composed of three subunits, a, b, and c, in the proportion ab₂ C_n, where n ranges from 8 to 15 in various organisms; in yeast, it is 10.

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#Unit 6. System Physiology – Plant

Subunit c is a small (Mr 8,000), very hydrophobic polypeptide, consisting almost entirely of two transmembrane helices, with a small loop extending from the matrix side of the membrane

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#Id: 3343

#Unit 6. System Physiology – Plant

TLS Online TPP Program

#Id: 3344

#Unit 6. System Physiology – Plant

Each c subunit has a critical Asp (or Glu) residue about midway across the membrane, which can donate or accept a proton.