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Identification of order and disorder in protein XPA


EMSL Project ID
2363

Abstract

The DNA repair protein Xeroderma pigmentosum group A (XPA) is a crucial component of the nucleotide excision repair pathway. The structure of full-length XPA has proved intractable by both NMR and X-ray crystallography and there is only limited structural knowledge for approximately one-third of the protein, the minimal binding domain (MBD). NMR solution structures of the MBD revealed that ~30% of its amino acids could not be assigned. XPA is a potential example of an intrinsically unstructured protein whose flexibility facilitates complex interactions without sacrificing specificity. To better characterize structural features of full-length XPA, we will perform time-resolved trypsin proteolysis on active recombinant Xenopus XPA (xXPA). The resulting proteolytic fragments will be analyzed by electrospray ionization interface coupled to a Fourier transform ion cyclotron resonance mass spectrometer and SDS-polyacrylamide gel electrophoresis (PAGE). The molecular weight of the full-length xXPA will be determined by mass spectrometry and compared with that calculated from the sequence (30922.45 Da). Moreover, the mass spectrometric data will allow the assignment of multiple xXPA fragments not resolvable by SDS-PAGE.

Project Details

Project type
Exploratory Research
Start Date
2001-10-16
End Date
2002-09-24
Status
Closed

Team

Principal Investigator

Lilia Lakoucheva
Institution
Pacific Northwest National Laboratory

Team Members

Eric Ackerman
Institution
Sandia National Laboratory

Related Publications

Aberrant mobility phenomena of the DNA repair protein XPA
Identification of intrinsic order and disorder in the DNA repair protein XPA