Research at a Glance:
Methodological Focus
Schulten began his research thirty years ago as a theoretical physicist. His academic career in physics focussed early on exclusively on biological research problems. His original discipline, though, is reflected in the high methodological level of his work. Among the methods Schulten developed are: the theory of first passage times [14] and its generalization [15]; Brownian dynamics [16,17]; topology representing neural networks [18]; the application of classical and quantum mechanical non-equilibrium statistical mechanics to biomolecular systems as in velocity echoes [19], in MRI microscopy [20] of quantum chemistry methods to molecular biology as reflected in his ground breaking work on polyene excited states [23,24] as well as in his long investigations on bacteriorhodopsin suggesting that retinal acts as a proton switch [25], explaining how the protein catalizes retinal's sterochemistry [26,27] and describing the quantum dynamics of retinal's femtosecond photoisomerization [28,29]. In molecular modelling, Schulten introduced multiple time scale integration [30] and together with J. Board of Duke U. the O(N) multipole algorithm for electrostatics [31].
Schulten's advances were based on systematic efforts in developing methods in computational biology that include hardware and software engineering. For example, he combined cameras, computer vision hardware and a parallel computer with a softarm robot to study visuo-motor control through neural networks [32,33].
With his collaborators during 1988-92, he designed, built and programmed a 60 processor parallel computer for molecular dynamics [ 34] that ran nearly uninterrupted for two years a simulation of a 27,000 atom lipid bilayer-water system and demonstrated a close agreement between computation and observation [49], establishing modern membrane modeling. In 1993, Schulten's group configured a cluster of workstations linked through an optical switch and developed for it a new molecular dynamics program that provided a powerful and extremely cost effective route to the modeling of large biomolecular systems, still unrivaled today [ 35]. The respective molecular dynamics program (NAMD1), written in the C++ language as all of the software in Schulten's group, is distributed free of charge in the research community and is under continuous development in close collaboration with computer scientists L. Kale and R. Skeel. Today the program (NAMD) runs efficiently on up to hundreds of processors [36] and includes all key features of modern modelling tools like periodic boundary conditions, NpT ensemble simulation and the particle mesh Ewald method for exact electrostatics. Schulten's group develops and distributes also the program VMD for molecular graphics [37 ] that has been combined with NAMD2 to steer molecular modelling visually and interactively as described in [35]. This software and other programs under development permitting web-based computing and collaborations in structural biology [38] are freely available through the group's web site.
