Despite the expansive applications of gas-phase unfolding techniques,the molecular mechanism for the solvent-free forced unfolding pathway which substrate multidomain proteins usually adopt remains elusive at the seco...Despite the expansive applications of gas-phase unfolding techniques,the molecular mechanism for the solvent-free forced unfolding pathway which substrate multidomain proteins usually adopt remains elusive at the secondary structure level.Herein,upon carefully selecting CRM_(197) as a therapeutically-relevant model system containing multiple secondary structure-separated domains,we systematically examine its solvent-free unfolding pathway.Further-more,utilizing the hybrid of noncovalent chemical probing with niacinamide and ion mobility-mass spectrometry-guided all-atom molecular dynamics simulations,we map a nearly complete unfolding atlas for the conjugate vaccine carrier protein CRM_(197) in a domain-and secondary structure-resolved manner.The totality of our data supports the preferential unfolding of the sheet-rich domain,indicating the dynamic transition from β-sheet toα-helix,and demonstrating that helix exhibit comparatively higher stability thanβ-sheets.We propose that this sheet-to-helix dynamic transition may be central to the gas-phase unfolding pathways of multidomain proteins,suggesting the need for systematic studies on additional multidomain protein systems.展开更多
Untargeted metabolomics aims to comprehensively profile metabolites as many as possible in biological samples.Recently,ion mobility-mass spectrometry(IM-MS)has emerged as a powerful technology for untargeted metabolom...Untargeted metabolomics aims to comprehensively profile metabolites as many as possible in biological samples.Recently,ion mobility-mass spectrometry(IM-MS)has emerged as a powerful technology for untargeted metabolomics.The emerging role of IM-MS in untargeted metabolomics enables the separation of metabolite isomers and generation of multidimension data to support the identification of metabolites.In this review,we first introduced the basic principles of IM-MS instruments commonly used for untargeted metabolomics.Then,we demonstrated the application of IM-MS for metabolite separation and identification of both known and unknown metabolites.Finally,we discussed the future developments of IM-MS technology to improve untargeted metabolomics.展开更多
基金support by the National Key R&D Program of China(No.2022YFA1305200,to GL)National Natural Science Foundation of China(No.22104064 to GL,No.22173020 to JL)the US National Institute of Mental Health(No.R01MH122742,to CJW)for financial and instrumental support.
文摘Despite the expansive applications of gas-phase unfolding techniques,the molecular mechanism for the solvent-free forced unfolding pathway which substrate multidomain proteins usually adopt remains elusive at the secondary structure level.Herein,upon carefully selecting CRM_(197) as a therapeutically-relevant model system containing multiple secondary structure-separated domains,we systematically examine its solvent-free unfolding pathway.Further-more,utilizing the hybrid of noncovalent chemical probing with niacinamide and ion mobility-mass spectrometry-guided all-atom molecular dynamics simulations,we map a nearly complete unfolding atlas for the conjugate vaccine carrier protein CRM_(197) in a domain-and secondary structure-resolved manner.The totality of our data supports the preferential unfolding of the sheet-rich domain,indicating the dynamic transition from β-sheet toα-helix,and demonstrating that helix exhibit comparatively higher stability thanβ-sheets.We propose that this sheet-to-helix dynamic transition may be central to the gas-phase unfolding pathways of multidomain proteins,suggesting the need for systematic studies on additional multidomain protein systems.
基金The work was supported by National Natural Science Foundation of China(Grant No.31971356)Shang-hai Municipal Science and Technology Major Project(Grant No.2019SHZDZX02)。
文摘Untargeted metabolomics aims to comprehensively profile metabolites as many as possible in biological samples.Recently,ion mobility-mass spectrometry(IM-MS)has emerged as a powerful technology for untargeted metabolomics.The emerging role of IM-MS in untargeted metabolomics enables the separation of metabolite isomers and generation of multidimension data to support the identification of metabolites.In this review,we first introduced the basic principles of IM-MS instruments commonly used for untargeted metabolomics.Then,we demonstrated the application of IM-MS for metabolite separation and identification of both known and unknown metabolites.Finally,we discussed the future developments of IM-MS technology to improve untargeted metabolomics.
