Proline residues dehydrogenases

Fig. 15. Stereo drawing of a bent helix (glyceraldehyde-phosphate dehydrogenase residues 146-161) with an internal proline. The proline ring produces steric hindrance to the straight a-helical conformation as well as having no NH group available for a hydrogen bond. A proline is the commonest way of producing a bend within a single helix, as well as occurring very frequently at the comers between helices.

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