Quasi-simultaneous imaging/pulling analysis of single polyprotein molecules by atomic force microscopy.
Most of studies in protein nanomechanics have used the atomic force microscope (AFM) in its force-measuring mode on immobilized protein repeats (polyproteins) as single-molecule markers. Here, we add imaging capabilities to a standard, state-of-the-art AFM "puller" and integrate the most powerful programs of analysis available for both AFM modes. This unique instrument allows high-resolution, quasi-simultaneous imaging/force spectroscopy in aqueous solution. We demonstrate its capabilities using polyproteins of a model system (titin I27 domain). This tool should greatly facilitate the development of a much needed universal functionalization system for AFM, one that should allow better sample control and an improved efficiency of protein immobilization.
Instituto Cajal, CSIC and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), E-28002 Madrid, Spain.
Alejandro
A
Valbuena
Javier
J
Oroz
Andrés Manuel
AM
Vera
Alejandro
A
Gimeno
Julio
J
Gómez-Herrero
Mariano
M
Carrión-Vázquez
D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation* / Q000379:methods; D008846:Micromanipulation / Q000295:instrumentation* / Q000379:methods; D018625:Microscopy, Atomic Force / Q000295:instrumentation* / Q000379:methods; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry* / Q000648:ultrastructure*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D013048:Specimen Handling / Q000295:instrumentation* / Q000379:methods; D013314:Stress, Mechanical
D011506:Proteins