EXAMPLE ligand.dpf file. Notes appear below. Written by Marty Pagel Reviewed by Karl Scheidt. types CNOH # atom type names fld cruzdok_maps.fld # grid data file map cruzdok_C.map # C-atomic affinity map map cruzdok_N.map # N-atomic affinity map map cruzdok_O.map # O-atomic affinity map map cruzdok_H.map # H-atomic affinity map map cruzdok_e.map # electrostatics map move lig.pdbq # small molecule about -15.475 -4.374 12.172 # small molecule center tran0 random # initial coordinates/A quat0 random # initial quaternion:unit-vector(qx,qy,qz);angle/deg(qw) ndihe 11 # numbe of dihedral angles to change during the run dihe0 random #initial dihedrals/deg tstep 0.05 # translation step/A qstep 1. # quaternion step/deg dstep 1. # torsion step/deg trnrf 1. # trans reduction factor/per cycle quarf 1. # quat reduction factor/per cycle dihrf 1. # tors reduction factor/per cycle intnbp 1272653.000 1127.684 12 6 # C-C internal energy non-bond parameters/Cn,Cm,n,m intnbp 610155.100 783.345 12 6 # C-N internal energy non-bond parameters/Cn,Cm,n,m intnbp 588883.800 633.754 12 6 # C-O internal energy non-bond parameters/Cn,Cm,n,m intnbp 88604.240 226.910 12 6 # C-H internal energy non-bond parameters/Cn,Cm,n,m intnbp 266862.200 546.765 12 6 # N-N internal energy non-bond parameters/Cn,Cm,n,m intnbp 249961.400 445.918 12 6 # N-O internal energy non-bond parameters/Cn,Cm,n,m intnbp 39093.660 155.983 12 6 # N-H internal energy non-bond parameters/Cn,Cm,n,m intnbp 230584.400 368.677 12 6 # O-O internal energy non-bond parameters/Cn,Cm,n,m intnbp 38919.640 124.049 12 6 # O-H internal energy non-bond parameters/Cn,Cm,n,m intnbp 1908.578 46.738 12 6 # H-H internal energy non-bond parameters/Cn,Cm,n,m rt0 500. # initial RT rtrf 0.95 # RT reduction factor/per cycle runs 1 # number of runs cycles 355 # number of cycles accs 300000 # steps accepted rejs 300000 # steps rejected select m # minimum or last outlev 2 # diagnostic output level rmstol 0.5 # cluster tolerance/A trjfrq 100000 # trajectory frequency trjbeg 1 # start trj output at cycle trjend 355 # end trj output at cycle trjout lig.trj # trajectory file trjsel A # A=acc only;E=either acc or rej extnrg 1000. # external grid energy Notes about this file: 1. Each run produces a separate docked ligand. You need more than 1 run if you perform culstering. 2. Each run consists of a number of cycles (you can set the number of cycles by setting "cycles ###" above). 3. At the start of each cycle, the coordinates of the ligand are randomly changed. If the resulting structure is LOWER in energy, this step is always accepted. If the resulting structure is HIGHER in energy, this step may be accepted based upon the Boltzman probability distribution (see manual). In other words, when the temperature is high, many steps that are higher in energy than the previous step are accepted; when the temperature is low, few steps that are higher in energy than the previous step are accepted. When the total number of accepted or rejected steps meets the 'accs' or 'rejs' numbers you type in above, then that cycle is finished. 4. When a new cycle begins, the minimum or last structure from the previous cycle is used (depending if 'select' is 'm' or 'l'). The temperature for the cycle is set to: (previous cycle temp)(rtrf) 5. Structures that have and RMSD < rmstol when they are superimposed will be 'binned' together (e.g., the program will 'cluster' these structures and tell you that they are part fo the same family of structures.) 6. A trajectory frame is saved every trjfrq steps. Make sure that the 'trjout' file exists and is empty before starting autodock. 7. Don't forget to include ndihe and dihe0, or your totatable bonds won't rotate. 8. While our results are preliminary, it appears that the calculation rejects all steps once the temperature is < 2 or 3K. Therefore, the number of cycles should be set to: cycles = ln(2/rt0) / ln(rtrf) It also appears that rt0 = 500 is OK. Finally, we think the rate of cooling should be as slow as reasonalbly possible. We set rtrf=0.99 and accs=rejs=80000. A typical calculation with these parameters and run=1 is about 6 hours on a Indy 180 MHz R5000SC.