Wilfred van Gunsteren: 35 Years of Biomolecular Simulation.

T special issue of the Journal of Chemical Theory and Computation is dedicated to one of the founders of the field of biomolecular simulation, Prof. Wilfred F. van Gunsteren, in honor of his 65th birthday and 35 years of research in this field. The description of biological processes at the molecular level is one of the greatest challenges in theoretical biology, and the key to understanding how biomolecules, biomolecular systems, cells, and, ultimately, living organisms function. In turn, the description of molecular properties at the (sub)atomic level is rooted in the field of theoretical physics, namely, in the laws of quantum mechanics or of its classical Newtonian approximation, the connection between microscopic and macroscopic levels being provided by statistical mechanics. Biomolecular simulation therefore bridges a broad spectrum of scientific disciplines, and it is not surprising to see that many key players in this field, such as Wilfred, combine a strong background in physics with a deep appreciation of both chemistry and biology. Biomolecular simulation is nowadays a well-established yet still rapidly evolving field. Scientists happily dwelling in a mature scientific area generally do so because they are standing “on the shoulders of giants”, in this case, the pioneers who dreamed once about simulating the molecules of life based on the laws of physics, designed the basic methods and algorithms to do so, programmed them into computers, and made their dream come true. It is beyond doubt that Wilfred was one of these pioneers. His contributions to the toolkit, the applications, and even the “philosophy” of biomolecular simulation over more than three decades are extensive and varied. Owing to his innovative mind, scientific rigor, unbounded energy, and strong personal charisma, Wilfred is definitely one of the “giants” of the field. Wilfred was born on August 7, 1947, in the town of Wassenaar in The Netherlands as Willem Frederik van Gunsteren, youngest child in a family of eight. As an undergraduate, he studied physics at the Free University of Amsterdam (“Vrije Universiteit Amsterdam”), obtaining his bachelor's degree (“kandidaats”) in 1968 and his master's degree (“doctoraal”) cum laude in 1972. Wilfred undertook his doctoral work in nuclear physics under the supervision of Prof. Dr. Egbert Boeker, was awarded the Royal Dutch−Shell Prize (1975) for this work, and obtained his Ph. D. cum laude in 1976. In addition to studying physics, Wilfred also prepared (without actually following the lectures!) a master's degree in law (“meester in de rechten”), which he obtained in 1974. While he never formally worked as a lawyer, the unusual combination of law and physics has been visible throughout his later career, in the form of a keen interest in matters of correctness, integrity, and justice, and in the careful formulation of arguments. Despite having just completed a highly successful Ph. D., Wilfred was unsure whether he wanted to pursue a career in nuclear physics. It was at this point that hemet Prof. Herman J. C. Berendsen, professor of physical chemistry at the University of Groningen. Herman convinced Wilfred that his skills in physics and computation might enable him to address fundamental questions in biology, a new and radical idea for the time. Wilfred worked with Herman at the University of Groningen as a postdoctoral fellow from 1976 to 1978, developing the basic algorithms and programs needed to efficiently simulate (bio)molecular systems. This period was followed by a second postdoctoral stay from 1978 to 1980 in the group of Prof. Martin Karplus at Harvard University, another leading center in this rapidly developing field. These years were important ones, not only scientifically but also privately: Wilfred and his wife Jolande, who had married in December 1970, became parents of two children, Job, born in 1976, and Eva, born in 1978. It was at Harvard that Wilfred began to write the code that would ultimately form the basis of the GROMOS (GROningen MOlecular Simulation) package, which he was to develop and refine over the course of his career. He returned from the U.S. in 1980 to take a position of senior lecturer at the University of Groningen, and became professor of physical chemistry at this university in 1987. From 1987 to 1988, he also spent one year at the University of California in San Francisco (UCSF), where he worked with his friend, the late Prof. Peter A. Kollman. In early 1990, Wilfred accepted an offer of the Eidgenössische Technische Hochschule (ETH) in Zürich and moved to Switzerland to become professor of computer-aided chemistry (“informatikgestützte chemie”) in September of that year. Wilfred has received numerous honors and prizes. Notable examples include the gold medal of the Royal Dutch Union of Chemists (1987) and the Max-Planck Forschungspreis für Chemie and Pharmazie (2002). Wilfred was also made Stiftungsgastprofessur für Chemie and Medizin of the Johann Wolfgang Goethe-Universitaẗ in Frankfurt (1988), corresponding member of the Royal Dutch Academy of Arts and Sciences (1995), 73rd Priestly Lecturer of Penn State University (1999), and 10th Huygens Lecturer of the Dutch Science Foundation (2001). Last but not least, Wilfred recently received the Golden Tricycle award of the Academic Association of Scientific Staff at ETH Zürich (2009), a unique prize awarded to group leaders at ETH for their support of family friendly policies. Wilfred has supervised nearly 50 Ph. D. students and as many postdoctoral