1JTN

Alternative Structures of a Sequence Extended T4 Lysozyme Show that the Highly Conserved Beta-Sheet Region has weak intrinsic Folding Propensity

1JTN の概要

• エントリーDOI: 10.2210/pdb1jtn/pdb
• 関連するPDBエントリー: 1JTM
• 分子名称: LYSOZYME, SULFATE ION (3 entities in total)
• 機能のキーワード: sequence duplication, context dependent folding, sequence repeat, hydrolase
• 由来する生物種: Enterobacteria phage T4
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 40634.53

構造登録者

Sagermann, M.,Matthews, B.W. (登録日: 2001-08-21, 公開日: 2002-03-20, 最終更新日: 2023-08-16)

主引用文献

Sagermann, M.,Matthews, B.W.
Crystal Structures of a T4-lysozyme Duplication-extension Mutant Demonstrate that the Highly Conserved beta-Sheet Region has Low Intrinsic Folding Propensity
J.Mol.Biol., 316:931-940, 2002

PubMed Abstract: Residues 24 to 35 of T4 lysozyme correspond to the second and third strands of a region of beta-sheet that is highly conserved in all known lysozyme and chitinase structures. To evaluate the intrinsic propensity of these amino acid residues to form a defined structure they were added at the C terminus of the native protein, together with a dipeptide linker. Two crystal structures of this active, mutant protein were obtained, to 1.9A and 2.3A resolution, respectively. Even though the crystal conditions are similar, the appended sequence adopts very different secondary structures. In one case it is weakly structured and appears to extend through the active-site cleft, perhaps in part adding an extra strand to the original beta-sheet. In the other crystal form the extension is largely alpha-helical. The formation of these alternative structures shows that the sequence does not have a strong intrinsic propensity to form a unique fold (either beta-sheet or otherwise). The results also suggest that structural conservation during evolution does not necessarily depend on sequence conservation or the conservation of folding propensity.

PubMed: 11884133
DOI: 10.1006/jmbi.2001.5376

実験手法

X-RAY DIFFRACTION (2.3 Å)