| Citation | Helen Saibil is internationally recognised for her application and development of cryoelectron microscopic image analysis to the dynamic behaviour of large (mega-Dalton) protein complexes in solution. Her remarkable cryo-EM images of the chaperonin complexes, revealing large, rigid-body domain movements pre-dated (and were largely confirmed by) crystallographic studies at higher resolution. Since then she has skilfully combined the static crystallographic information with the lower resolution (7-30Å) cryo-EM data to greatly extend the range of structure determination. More importantly, by integrating biochemical, kinetic and genetic approaches with time-resolved cryo-EM, her work has yielded valuable insights into the multiple, dynamic structural changes which accompany the function of these biological nanomachines. (The moving images of the chaperonins-in-action which she has generated are best seen at Saibil's home page, www.cryst.bbk.ac.uk/~ubcg16z/chaperone.html) Most recently, she has successfully investigated the structural transitions associated with two important diseases, the formation of fibrils associated with amyloid disease and membrane pore formation by pneumolysin, the toxin of bacteria which cause pneumonia. |