Amide proton exchange in the alpha-amylase polypeptide inhibitor Tendamistat studied by two-dimensional 1H nuclear magnetic resonance.
The individual amide proton exchange rates in Tendamistat at pH 3.0 and 50 degrees C were measured by using two-dimensional 1H nuclear magnetic resonance. Overall, it was found that the distribution of exchange rates along the sequence is dominated by the interstrand hydrogen bonds of the beta-sheet structures. The slowly exchanging protons in the core of the two beta-sheets were shown to exchange via an EX2 mechanism. Further analysis of the data indicates that different large-scale structure fluctuations are responsible for the exchange from the two beta-sheets, even though the three-dimensional structure of Tendamistat appears to consist of a single structural domain.
Wang
Q W
QW
Institut für Molekularbiologie und Biophysik, Eidgenössische Technische Hochschule Zürich-Hönggerberg, Switzerland.
Kline
A D
AD
Wüthrich
K
K
D000577:Amides; D000595:Amino Acid Sequence; D006859:Hydrogen; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D010455:Peptides; D011522:Protons; D000516:alpha-Amylases / Q000037:antagonists & inhibitors*
D000577:Amides; D010455:Peptides; D011522:Protons; D006859:Hydrogen; D000516:alpha-Amylases; C030526:tendamistate