无溶剂可及半胱氨酸残基的CAP衍生物，或在螺旋-转角-螺旋基序的第2位氨基酸处有独特溶剂可及半胱氨酸残基的CAP衍生物。

Derivatives of CAP having no solvent-accessible cysteine residues, or having a unique solvent-accessible cysteine residue at amino acid 2 of the helix-turn-helix motif.

作者信息

Zhang X P, Gunasekera A, Ebright Y W, Ebright R H

机构信息

Department of Chemistry and Waksman Institute, Rutgers University, New Brunswick, NJ 08855.

出版信息

J Biomol Struct Dyn. 1991 Dec;9(3):463-73. doi: 10.1080/07391102.1991.10507929.

DOI:10.1080/07391102.1991.10507929

PMID:1667734

Abstract

The Escherichia coli catabolite gene activator protein (CAP) is a helix-turn-helix motif sequence-specific DNA binding protein. CAP contains a unique solvent-accessible cysteine residue at amino acid 10 of the helix-turn-helix motif. In published work, we have constructed a prototype semi-synthetic site-specific DNA cleavage agent from CAP by use of cysteine-specific chemical modification to incorporate a nucleolytic chelator-metal complex at amino acid 10 of the helix-turn-helix motif [Ebright, R., Ebright, Y., Pendergrast, P.S. and Gunasekera, A., Proc. Natl. Acad. Sci. USA 87, 2882-2886 (1990)]. Construction of second-generation semi-synthetic site-specific DNA cleavage agents from CAP requires the construction of derivatives of CAP having unique solvent-accessible cysteine residues at sites within CAP other than amino acid 10 of the helix-turn-helix motif. In the present work, we have constructed and characterized two derivatives of CAP having no solvent-accessible cysteine residues: [Ser178]CAP and [Leu178]CAP. In addition, in the present work, we have constructed and characterized one derivative of CAP having a unique solvent-accessible cysteine residue at amino acid 2 of the helix-turn-helix motif: [Cys170;Ser178]CAP.

摘要

大肠杆菌分解代谢基因激活蛋白（CAP）是一种具有螺旋-转角-螺旋基序的序列特异性DNA结合蛋白。CAP在螺旋-转角-螺旋基序的第10位氨基酸处含有一个独特的可溶剂接触的半胱氨酸残基。在已发表的工作中，我们通过使用半胱氨酸特异性化学修饰，在螺旋-转角-螺旋基序的第10位氨基酸处掺入一个核酸裂解螯合剂-金属复合物，从CAP构建了一种原型半合成位点特异性DNA裂解剂[Ebright, R., Ebright, Y., Pendergrast, P.S.和Gunasekera, A., Proc. Natl. Acad. Sci. USA 87, 2882-2886 (1990)]。从CAP构建第二代半合成位点特异性DNA裂解剂需要构建CAP的衍生物，这些衍生物在螺旋-转角-螺旋基序第10位氨基酸以外的CAP位点具有独特的可溶剂接触的半胱氨酸残基。在本研究中，我们构建并表征了两种没有可溶剂接触半胱氨酸残基的CAP衍生物：[Ser178]CAP和[Leu178]CAP。此外，在本研究中，我们构建并表征了一种在螺旋-转角-螺旋基序第2位氨基酸处具有独特的可溶剂接触半胱氨酸残基的CAP衍生物：[Cys170;Ser178]CAP。