Binding of calcium in the EF‐hand of Escherichia coli lytic transglycosylase Slt35 is important for stability

FEBS Letters

Dijkstra, Bauke W¹  van Asselt, Erik J¹ 

[1] BIOSON Research Institute and Laboratory of Biophysical Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands

关键词: EF-hand;    Lytic transglycosylase;    Thermostability;    Crystal structure;    Calcium;    Escherichia coli;   

DOI  :  10.1016/S0014-5793(99)01198-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The Escherichia coli lytic transglycosylase Slt35 contains a single metal ion-binding site that resembles EF-hand calcium-binding sites. The Slt35 EF-hand is only the second observation of such a domain in a prokaryotic protein. Two crystal structures at 2.1 Å resolution show that both Ca²⁺ ions and Na⁺ ions can bind to the EF-hand domain, but in subtly different configurations. Heat-induced unfolding studies demonstrate that Ca²⁺ ions are preferentially bound, and that only Ca²⁺ ions significantly increase the melting temperature of Slt35. This shows that the EF-hand calcium-binding domain is important for the stability of Slt35.

【 授权许可】

Unknown