紫外激光解离质谱揭示n端融合标签对重组蛋白构象影响机制

Key Points

• This study aims to understand how N-terminal fusion tags affect the stability of recombinant protein conformations using ubiquitin as a model.
• Developed a non-denaturing mass spectrometry (nMS) strategy combined with 193 nm UV laser dissociation (UVPD)
• Analyzed the effects of N-terminal fusion tags (His-TEV, His-FLAG, SUMO) on ubiquitin at the single residue level
• Evaluated changes in charge state distribution and conformation of ubiquitin
• Fusion tags significantly alter the overall charge distribution of ubiquitin
• Different tags induce specific local conformation changes, particularly around the fusion site
• His-FLAG increases N-terminal rigidity while inducing unfolding locally
• His-TEV considerably destabilizes the N-terminal structure
• SUMO tag rearranges complex internal hydrogen bonding network