Nature 277, 578 (15 February 1979); doi:10.1038/277578a0

Protein structural fluctuations during a period of 100 ps

M. KARPLUS & J. A. MCCAMMON^*

Department of Chemistry, Harvard University, Cambridge, Massachusetts 02138
^*Present address: Department of Chemistry, University of Houston, Houston, Texas 77004.

A RECENT 9-ps molecular dynamics simulation¹ of the bovine pancreatic trypsin inhibitor (PTI) at 295 K revealed a rich variety of motional phenomena at the atomic level on a picosecond time scale. To obtain information about longer time processes, and to characterise more accurately the short time results, a 96-ps dynamical simulation of PTI at an average temperature of 306 K has been completed with the techniques used previously¹; an extended equilibration period of 72 ps before simulation served to eliminate internal stresses. Analysis of the present simulation has confirmed most of the conclusions of the earlier study but has shown in addition that there are significant features of the dynamics that can be observed only over a longer period, 100 ps.

References

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