201L

HOW AMINO-ACID INSERTIONS ARE ALLOWED IN AN ALPHA-HELIX OF T4 LYSOZYME

201L の概要

• エントリーDOI: 10.2210/pdb201l/pdb
• 分子名称: T4 LYSOZYME, BETA-MERCAPTOETHANOL (3 entities in total)
• 機能のキーワード: hydrolase(o-glycosyl)
• 由来する生物種: Enterobacteria phage T4
• 細胞内の位置: Host cytoplasm : P00720
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 37883.52

構造登録者

Heinz, D.W.,Matthews, B.W. (登録日: 1993-10-12, 公開日: 1994-01-31, 最終更新日: 2024-02-14)

主引用文献

Heinz, D.W.,Baase, W.A.,Dahlquist, F.W.,Matthews, B.W.
How amino-acid insertions are allowed in an alpha-helix of T4 lysozyme.
Nature, 361:561-564, 1993

PubMed Abstract: Studies of extant protein sequences indicate that amino-acid insertions and deletions are preferentially located in loop regions, which has traditionally been explained as the result of selection removing deleterious mutations within secondary structural elements from the population. But there is no a priori reason to discount the possibility that insertions within secondary structure could either be tolerated until compensatory mutations arise, or have effects that are propagated away from secondary structure into loops. Earlier studies have indicated that insertions are generally tolerated, although much less well within secondary structure elements than in loop regions. Here we show that amino-acid insertions in an alpha-helix of T4 lysozyme can be accepted in two different ways. In some cases the inserted amino acids are accommodated within the helix, leading to the translocation of wild-type residues from the helix to the preceding loop. In other cases the insertion causes a 'looping-out' in the first or last turn of the helix. The individual structural responses seem to be dominated by the maintenance of the interface between the helix and the rest of the protein.

PubMed: 8429913
DOI: 10.1038/361561a0

実験手法

X-RAY DIFFRACTION (2 Å)