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Updated: Aug 14, 2026

From Constructs to Crystals – Towards Structure Determination of β-barrel Outer Membrane Proteins
Published on: July 4, 2016
Structure-function correlation of outer membrane protein porin from Paracoccus denitrificans
S Sukumaran1, K Hauser, E Maier
1Institut für Biophysik, Johann Wolfgang Goethe-Universität, Max von Laue-Strasse 1, 60438 Frankfurt am Main, Germany.
Abstract:
Porins from outer membrane of Gram-negative bacteria have a highly stable structure. Our previous studies on porin from Paracoccus denitrificans showed that the outer membrane protein porin is extremely stable toward heat, pH, and chemical denaturants. The major question we have addressed in this paper is whether the high stability of porin is a consequence of the beta-barrel structure and whether it is required for its function. To explain this we have analyzed two cases: first, we used porin wild-type and mutants and compared their structure and function; second, we compared the activity of porin preheated to different temperatures. Structural changes were monitored by infrared spectroscopy. We observed that the structural stability of porin is not equivalent to functional activity as minor alteration in the structure can result in drastic differences in the activity of porins.
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