Heat shock in Escherichia coli alters the protein-binding properties of the chaperonin groEL by inducing its phosphorylation

摘要: WHEN bacterial or enkaryotic cells are exposed to high temperatures other harsh conditions, they respond by synthesis of a specific set heat-shock proteins1–3 Certain proteins such as groEL, called 'chaperonins', can prevent misfolding and promote the refolding proper assembly unfolded polypeptides generated under harmful conditions2,4. We report here new aspect response in Escherichia coli: at fraction groEL becomes modified covalently, altering its interaction with proteins. The heat-modified form be eluted ATP from an protein more easily than normal groEL. critical heat-induced modification seems phosphorylation, which is reversed on return low temperature. Treatment phosphatases caused apparent size, charge binding properties resemble those unmodified form. Thus during heat shock some reversibly phosphorylated, allows ATP-dependent release substrates in- absence usual cofactor (groES), probably promotes repair damaged polypeptides.