Plasticity of secondary structure in the N-terminal region of β-dystroglycan

被引：17

作者：

Boffi, A

Bozzi, M

Sciandra, F

Woellner, C

Bigotti, MG

Ilari, A

Brancaccio, A

机构：

[1] Univ Roma La Sapienza, Dipartimento Sci Biochim, CNR, Ctr Mol Biol, I-00185 Rome, Italy

[2] Univ Roma Tor Vergata, Dipartimento Sci & Tecnol Chim, I-00133 Rome, Italy

[3] Univ Cattolica Sacro Cuore, Ist Chim Chim Clin, CNR, Ctr Chim Recettori, I-00168 Rome, Italy

[4] Subasen Med Univ Sulinin, Rheuma Zentrum, D-79106 Freiburg, Germany

来源：

BIOCHIMICA ET BIOPHYSICA ACTA-PROTEIN STRUCTURE AND MOLECULAR ENZYMOLOGY | 2001年 / 1546卷 / 01期

关键词：

dystroglycan; natively unfolded protein; secondary structure determination; infrared spectroscopy; circular dichroism spectroscopy;

D O I：

10.1016/S0167-4838(01)00131-5

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

The secondary structure content of the N-terminal extracellular domain of beta -dystroglycan (a recombinant fragment extending from positions 654 to 750) has been quantitatively determined by means of CD and FTIR spectroscopies. The elements of secondary structure, namely an 8-10 residue long alpha -helix (10%) and two beta -strands (24%) have been assigned to specific amino acid sequences by means of a GOR constrained prediction method. The remaining 66% of the whole sequence is classified as turns or unordered. The temperature dependence of CD and FTIR spectra has been investigated in detail. A reversible, non-cooperative thermal transition is observed with both CD and FTIR spectroscopies up to 95 degreesC. The profile of the transition is typical of the unfolding of isolated peptides and corresponds to the progressive loss of the secondary structure elements of the protein with no evidence for collapsing phenomena, typical of globular proteins, upon heating. (C) 2001 Elsevier Science B.V. All rights reserved.

引用

页码：114 / 121

页数：8

共 26 条

[1] Sequence analysis suggests the presence of an IG-like domain in the N-terminal region of α-dystroglycan which was crystallized after mutation of a protease susceptible site (Arg168→His) [J].