Single-Molecule Measurement of Carbonic Anhydrase in Cation Coordinated Environment Using MspA Nanopore  

作　　者：Dandan Song Yunjiao Wang Shaoxia Zhang Lingyu Zhao Linyu Gong Liyuan Liang Liang Wang 

机构地区：[1]School of Optoelectronic Engineering,Chongqing University of Posts and Telecommunications,Chongqing,400065 China [2]Chongqing Institute of Green and Intelligent Technology,Chinese Academy of Sciences & Chongqing School,University of Chinese Academy of Sciences,Chongqing,400714 China

出　　处：《Chinese Journal of Chemistry》2023年第11期1341-1347,共7页中国化学（英文版）

基　　金：National Key Research and Development Program of China(2022YFB3205600);Chongqing Talents:Exceptional Young Talents Project(cstc2021ycjh-bgzxm0016);Beibei Technology Talents and Independent Innovation Project(No.2022-34);the Natural Science Foundation of Chongqing,China(cstc2021jcyj-jqx0030).

摘　　要：Carbonic anhydrase accounts for catalytic reaction of CO_(2)/HCO_(3)^(–) transformation, thus resulting in neutralization and acidification of the cellular environment, thereby favoring tumor development. Hence, it is a classical protein model of greatly biocatalytic significance as well as a highly expressed biomarker with renal tumor. We herein proposed a single-molecule measurement on carbonic anhydrase using MspA nanopore, in [BMIM+] and asymmetric K^(+)/Ca^(2+) cationic coordinated environment, instead of usual symmetric KCl/NaCl electrolyte. Significantly, our empirical analysis showed that asymmetric K^(+)/Ca^(2+) cationic environment contributes to distinguishable current modulations, thus yielding better resolution for carbonic anhydrase measurement, which is independent of applied voltage and more importantly, is stable enough at varied pH conditions and for very low concentration test in urine sample. Our results provide a classical model for nanopore protein analysis, and may also permit biocatalytic measurement at single-molecule level.

关 键 词：Carbonic anhydrase Nanopore biosensing Biocatalytic biophysical analysis Cation coordinated environment Renal tumorbiomarker Proteinmodel lonicchannel 

分 类 号：O64[理学—物理化学]