Our Major Collaborators:
3D cryo-electron microscopy with Alasdair Steven and James Conway
We have an active three way collaboration with James Conway in the Pitt Department of Structural Biology and Alasdair Steven at the Laboratory Of Structural Biology, National Institute of Arthritis and Musculoskeletal and Skin Diseases at the NIH. Together we have been studying HK97 capsid structure using 3 dimensional reconstructions from images made of well-preserved frozen-hydrated samples using cryo-electron microscopy done by Naiqian Cheng at the NIH . Much of this work has been published, including a study of the dynamics of maturation of HK97 Prohead II as it transforms into Head II as described in Lata, et al.,2000. This latter work resulted in the production of movies of the HK97 Prohead to Head transformation that are available on line (HK97 Movies online).
X-ray diffraction, biophysical and biochemical studies with Jack Johnson's Lab at TSRI.
We have an active collaboration with Jack Johnson's Lab at The Scripps Research Institute in La Jolla, CA. These include the completed HK97 Head II x-ray structure with Bill Wikoff, the structural and biochemical studies of HK97 expansion intermediates with Lu Gan (Gan, et al., 2004), fluorescence and small angle x-ray studies to monitor the dynamics of capsid structure during capsid maturation with Kelly Lee (Lee, et al., 2005) and (Lee, et al., 2004), the structure of Prohead II with Ilya Gertsman,(Gertsman, et al., 2009) and ongoing work including determining an X-ray crystal structure of Prohead I with Rick Huang.
Bill Wikoff grew crystals of HK97 Head II that diffracted x-rays beyond 3.5 Angstroms resolution and produced first crystallographic model of the HK97 mature empty capsid, the first of its kind. A detailed model of the HK97 head based on the near-atomic resolution structure was published in (Wikoff, et al.,2000) Science 289, 2129-33 and a refined structure and analysis in (Helgstrand, et el., 2003)