Fabs Enable Single Particle cryoEM Studies of Small Proteins

Shenping Wu, Agustin Avila-Sakar, JungMin Kim, David S. Booth, Charles H. Greenberg, Andrea Rossi, Maofu Liao, Xueming Li, Akram Alian, Sarah L. Griner, Narinobu Juge, Yadong Yu (+8 others)
2012 Structure  
In spite of its recent achievements, the technique of single particle electron cryomicroscopy (cryoEM) has not been widely used to study proteins smaller than 100 kDa, although it is a highly desirable application of this technique. One fundamental limitation is that images of small proteins embedded in vitreous ice do not contain adequate features for accurate image alignment. We describe a general strategy to overcome this limitation by selecting a fragment antigen binding (Fab) to form a
more » ... le and rigid complex with a target protein, thus providing a defined feature for accurate image alignment. Using this approach, we determined a three-dimensional structure of an $65 kDa protein by single particle cryoEM. Because Fabs can be readily generated against a wide range of proteins by phage display, this approach is generally applicable to study many small proteins by single particle cryoEM. Structure Single Particle cryoEM of Small Proteins Structure 20, 582-592, April 4,
doi:10.1016/j.str.2012.02.017 pmid:22483106 pmcid:PMC3322386 fatcat:hel4ksfv7zcejnkjupfwqtw5ha