Heat-induced conversion of ovalbumin into a proteinase inhibitor.

The Journal of Biological Chemistry
P MelletJ G Bieth

Abstract

Ovalbumin is a member of the serine proteinase inhibitor (serpin) family but is unable to inhibit proteinases. Here we show that heating transforms it into inhibitory ovalbumin (I-ovalbumin), a potent reversible competitive inhibitor of human neutrophil elastase (Ki = 5 nM) and cathepsin G (Ki = 60 nM) and bovine chymotrypsin (Ki = 30 nM). I-ovalbumin also inhibits bovine trypsin, porcine elastase and alpha-lytic proteinase with Ki values in the micromolar range. Thus, I-ovalbumin differs from active serpins by its inability to form irreversible complexes with proteinases. I-ovalbumin is unusually thermostable: it does not undergo any structural transition between 45 degrees C and 120 degrees C as tested by differential scanning calorimetry, and it retains full inhibitory capacity after heating at 120 degrees C. It has 8% less alpha-helices and 9% more beta-sheet structures than native ovalbumin, as shown by circular dichroism. Our results show that the primary sequence of ovalbumin contains the information required for enabling the first step of the serpin-proteinase interaction to occur, i.e. the formation of the Michaelis-like reversible complex, but does not contain the information needed for stabilizing this initial complex.

References

Feb 1, 1976·Journal of the Science of Food and Agriculture·J W Donovan, C J Mapes
Jun 15, 1992·Proceedings of the National Academy of Sciences of the United States of America·E Remold-O'DonnellM Alberts
Jul 31, 1980·Biochemical and Biophysical Research Communications·L T Hunt, M O Dayhoff
Jul 1, 1995·Proteins·H T Wright, J N Scarsdale
Oct 27, 1995·The Journal of Biological Chemistry·D A LawrenceJ D Shore
Apr 1, 1995·Protein Science : a Publication of the Protein Society·J A HuntingtonP G Gettins
Jan 1, 1995·Methods in Enzymology·J G Bieth
Oct 15, 1993·Proceedings of the National Academy of Sciences of the United States of America·P CoughlinP Bird
Feb 1, 1996·Plant Molecular Biology·S K RasmussenJ Hejgaard
Apr 1, 1965·Australian Journal of Biological Sciences·M B SMITH, J F BACK

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Citations

Sep 27, 2000·Biochimica Et Biophysica Acta·M R PeltierP J Hansen
Oct 19, 2004·Biochimica Et Biophysica Acta·Massimiliano CuccioloniMauro Angeletti
Jun 20, 2013·International Journal of Biological Macromolecules·Gulam Mohmad Rather, Munishwar Nath Gupta
Sep 3, 2021·Acta Crystallographica. Section D, Structural Biology·Barbora KascakovaIvana Kuta Smatanova
Oct 24, 2003·Analytical Chemistry·Jeremy D RamseyJ Michael Ramsey

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