Puzzle 412: Electron Density Trace Puzzle not identical but close to 1LA1 Structural plasticity and noncovalent substrate binding in the GroEL apical domain. A study using electrospay ionization mass spectrometry and fluorescence binding studies.Ashcroft, A.E., Brinker, A., Coyle, J.E., Weber, F., Kaiser, M., Moroder, L., Parsons, M.R., Jager, J., Hartl, U.F., Hayer-Hartl, M., Radford, S.E. part of 3CAU De novo backbone trace of GroEL from single particle electron cryomicroscopy. Ludtke, S.J., Baker, M.L., Chen, D.H., Song, J.L., Chuang, D.T., Chiu, W.