Angiotensin-converting enzyme 2(ACE2) is not only an enzyme but also a functional receptor on cell membrane for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Here, the activity of ACE2 in single living ...Angiotensin-converting enzyme 2(ACE2) is not only an enzyme but also a functional receptor on cell membrane for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Here, the activity of ACE2 in single living cell is firstly determined using a nanokit coupled electrospray ionization mass spectrometry(nanokit-ESI-MS). Upon the insertion of a micro-capillary into the living h ACE2-CHO cell and the electrochemical sorting of the cytosol, the target ACE2 enzyme hydrolyses angiotensin II inside the capillary to generate angiotensin 1-7. After the electrospray of the mixture at the tip of the capillary, the product is differentiated from the substrate in molecular weight to achieve the detection of ACE2 activity in single cells. The further measurement illustrates that the inflammatory state of cells does not lead to the significant change of ACE2 catalytic activity, which elucidates the relationship between intracellular ACE2 activity and inflammation at single cell level. The established strategy will provide a specific analytical method for further studying the role of ACE2 in the process of virus infection, and extend the application of nanokit based single cell analysis.展开更多
Cellular heterogeneity is essential for the physiological functions of organisms,and precise interpretation of the relevant biological mechanisms involved requires accurate measurement of biomolecules,including DNA,RN...Cellular heterogeneity is essential for the physiological functions of organisms,and precise interpretation of the relevant biological mechanisms involved requires accurate measurement of biomolecules,including DNA,RNA,proteins,and metabolites at the single-cell level.Cellular metabolites react most rapidly to environmental and biochemical changes such that their detection is a critical step in determining the physiological state of cells.However,their limited amounts,structural diversity,and significant content variation render single-cell metabolomics analysis technically challenging.Mass spectrometry,with its high sensitivity,good selectivity,and wide dynamic range,has been widely used in the single-cell analysis in recent years.In terms of ionization techniques,there are four main types of single-cell mass spectrometry methods:nano-electrospray ionization mass spectrometry,matrix-assisted laser desorption/ionization mass spectrometry,secondary ion mass spectrometry,and dielectric barrier discharge ionization mass spectrometry.In this mini review,the progress of single-cellmass spectrometrymethodologies and data processing strategies are summarized,and the future trends in single-cell mass spectrometry are outlined.展开更多
目的系统评价基质辅助激光解吸/电离飞行时间质谱法(matrix-assisted laser desorption/ionization time of flight mass spectrometry,MALDI-TOF-MS)检测食源性致病菌有效性.方法使用计算机检索中国期刊全文数据库、万方学术期刊全文...目的系统评价基质辅助激光解吸/电离飞行时间质谱法(matrix-assisted laser desorption/ionization time of flight mass spectrometry,MALDI-TOF-MS)检测食源性致病菌有效性.方法使用计算机检索中国期刊全文数据库、万方学术期刊全文数据库等数据库中通过MALDI-TOF MS鉴定食源性致病菌的相关文献.采用Review Manager 5.4软件进行Meta分析.结果MALDI-TOF-MS鉴定的有效性低于食品安全国家标准的传统培养法.结论MALDI-TOF-MS技术具有操作简便、高效的特点,在食品检验中值得推广应用,但仍然需要纳入更多高质量的文献做进一步证实.展开更多
基金supported by Ministry of Science and Technology of China(No.2017YFA0700500)the National Natural Science Foundation of China(Nos.22025403 and 21974060)+1 种基金Kuanren Talents Program of the Second Affiliated Hospital of Chongqing Medical UniversityYoung and Middle-aged Senior Medical Talents Studio of Chongqing。
文摘Angiotensin-converting enzyme 2(ACE2) is not only an enzyme but also a functional receptor on cell membrane for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Here, the activity of ACE2 in single living cell is firstly determined using a nanokit coupled electrospray ionization mass spectrometry(nanokit-ESI-MS). Upon the insertion of a micro-capillary into the living h ACE2-CHO cell and the electrochemical sorting of the cytosol, the target ACE2 enzyme hydrolyses angiotensin II inside the capillary to generate angiotensin 1-7. After the electrospray of the mixture at the tip of the capillary, the product is differentiated from the substrate in molecular weight to achieve the detection of ACE2 activity in single cells. The further measurement illustrates that the inflammatory state of cells does not lead to the significant change of ACE2 catalytic activity, which elucidates the relationship between intracellular ACE2 activity and inflammation at single cell level. The established strategy will provide a specific analytical method for further studying the role of ACE2 in the process of virus infection, and extend the application of nanokit based single cell analysis.
文摘Cellular heterogeneity is essential for the physiological functions of organisms,and precise interpretation of the relevant biological mechanisms involved requires accurate measurement of biomolecules,including DNA,RNA,proteins,and metabolites at the single-cell level.Cellular metabolites react most rapidly to environmental and biochemical changes such that their detection is a critical step in determining the physiological state of cells.However,their limited amounts,structural diversity,and significant content variation render single-cell metabolomics analysis technically challenging.Mass spectrometry,with its high sensitivity,good selectivity,and wide dynamic range,has been widely used in the single-cell analysis in recent years.In terms of ionization techniques,there are four main types of single-cell mass spectrometry methods:nano-electrospray ionization mass spectrometry,matrix-assisted laser desorption/ionization mass spectrometry,secondary ion mass spectrometry,and dielectric barrier discharge ionization mass spectrometry.In this mini review,the progress of single-cellmass spectrometrymethodologies and data processing strategies are summarized,and the future trends in single-cell mass spectrometry are outlined.
文摘目的系统评价基质辅助激光解吸/电离飞行时间质谱法(matrix-assisted laser desorption/ionization time of flight mass spectrometry,MALDI-TOF-MS)检测食源性致病菌有效性.方法使用计算机检索中国期刊全文数据库、万方学术期刊全文数据库等数据库中通过MALDI-TOF MS鉴定食源性致病菌的相关文献.采用Review Manager 5.4软件进行Meta分析.结果MALDI-TOF-MS鉴定的有效性低于食品安全国家标准的传统培养法.结论MALDI-TOF-MS技术具有操作简便、高效的特点,在食品检验中值得推广应用,但仍然需要纳入更多高质量的文献做进一步证实.
