Structure-Based Design of a Sulfonamide Probe for Fluorescence Anisotropy Detection of Zinc with a Carbonic Anhydrase-Based Biosensor

详细信息    查看全文

• 作者：Daniel Elbaum ; Satish K. Nair ; Marcia W. Patchan ; Richard B. Thompson ; and David W. Christianson
• 刊名：Journal of the American Chemical Society
• 出版年：1996
• 出版时间：September 4, 1996
• 年：1996
• 卷：118
• 期：35
• 页码：8381 - 8387
• 全文大小：363K
• 年卷期：v.118,no.35(September 4, 1996)
• ISSN：1520-5126

文摘

Given the avid and selective metal binding properties ofnaturally-occurring metalloproteins, it is possibleto exploit these systems in the development of novel sensors, i.e.,"biosensors", for the detection of trace quantitiesof metal ions. Here, we exploit the high affinity of humancarbonic anhydrase II (CAII) for zinc in the detection ofnanomolar concentrations of this metal ion by fluorescence anisotropyusing a fluorescein-derivatized arylsulfonamideprobe,4-aminosulfonyl[1-(4-N-(5-fluoresceinylthioureido)butyl)]benzamide(3). This probe was designed throughan iterative, structure-based approach and was demonstrated to bindtightly only to the zinc-bound holoenzyme(K_d= 2.3 nM) and not the metal-free apoenzyme. Furthermore, theprobe exhibits anisotropy that is proportional to theconcentration of bound zinc, and this behavior can be exploited in thedetection of zinc in the 10-1000 nM range.Strategies for the structure-based design of improved CAII-basedmetal ion biosensors are considered in view ofthese results.