Accelerated exchange of a buried water molecule in selectively disulfide-reduced bovine pancreatic trypsin inhibitor.

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

Using magnetic relaxation dispersion (MRD), we have previously shown that the four internal water molecules in bovine pancreatic trypsin inhibitor (BPTI) exchange with bulk water on time scales between 10(-8) and 10(-4) s at room temperature. Because this exchange is controlled by the protein structure, internal water molecules can be used to probe rare conformational fluctuations. Here, we report (2)H and (17)O MRD data at three temperatures for wild-type BPTI and two BPTI variants where the 14-38 disulfide bond has been cleaved by a double Cys --> Ser mutation or by disulfide reduction and carboxamidomethylation. The MRD data show that the internal water molecules are conserved on disulfide cleavage. However, the exchange rate of the water molecule buried near the disulfide bond is enhanced by 2-4 orders of magnitude. The relation of water exchange to other dynamic processes in BPTI is discussed.

Detaljer

Författare
Enheter & grupper
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Biokemi och molekylärbiologi
Originalspråkengelska
Sidor (från-till)12020-12027
TidskriftBiochemistry
Volym43
Utgivningsnummer38
StatusPublished - 2004
PublikationskategoriForskning
Peer review utfördJa