Dear Tom:

Thanks for your suggestion. You are absolutely right on doing more testings. I simply haven't figure out what the appropriate test is yet. Could you be more specific about "these parameters perform just as well as"? What kind of test did you do?

Also, is there a reason why you choose Amber over Charmm? Is it more "compatible" with OPLS?

Thanks,
Bin

On Jun 23, 2010, at 2:48 AM, Thomas Piggot wrote:

Well I would suggest you should do some very careful testing to validate the combination of CHARMM charges and one dihedral with the rest of the parameters from OPLS. It is not very common (or generally wise) to mix and match parameters from different forcefields, see:
http://www.gromacs.org/index.php?title=Documentation/How-tos/Parameterization

I would also say that you should also take care with the OPLS-AA DNA parameters as these have not been substantially tested/used and so you should double check the atom types for yourself.

On the specific topic of ATP for OPLS-AA/L I have performed simulations using the AMBER ATP parameters in OPLS-AA/L (with no changes for anything such as the different combination rules) and have found these parameters perform just as well as with the AMBER forcefields. There will be a section about this (showing the results from some of the tests I performed) in a paper I am currently writing.

The AMBER ATP parameters can be found at:

http://www.pharmacy.manchester.ac.uk/bryce/amber#cof

However, I would also ask is there a specific reason you wish to use OPLS-AA/L? If not then it is probably easier to use one of the AMBER forcefields with these parameters as you do not need to do any testing (or wait for me to publish my work!)

Cheers

Tom

BIN ZHANG wrote:
Hi, I recently made up a topology for ADP. You can probably modify it to ATP easily. I used native OPLS atom types based on the DNA parameters (http://rnp-group.genebee.msu.su/3d/ff.htm). The charges are copied from CHARMM27. Also, there is one dihedral angle missing, again, copied from CHARMM.
Please let me know if you have any question, suggestion, ....
Cheers,
Bin
===============================
In the ffoplsaa.rtp file, I added:
[ ADP ]
[ atoms ]
   PB    opls_440   1.100     0 ;P
  O1B    opls_441  -0.900     1 ;O
  O2B    opls_441  -0.900     2 ;O
  O3B    opls_441  -0.900     3 ;O
   PA    opls_440   1.500     4 ;P
  O1A    opls_441  -0.820     5 ;O2
  O2A    opls_441  -0.820     6 ;O2
  O3A    opls_442  -0.740     7 ;OS
  O5'    opls_442  -0.620     8 ;OS
  C5'    opls_443  -0.080     9 ;CT
 H5''    opls_444   0.090    10 ;HC
 H5'     opls_444   0.090    11 ;HC
  C4'    opls_158   0.160    12 ;CT
  H4'    opls_156   0.090    13 ;HC
  O4'    opls_180  -0.500    14 ;OS
  C1'    opls_158   0.160    15 ;CT
  H1'    opls_156   0.090    16 ;HC
   N9    opls_354  -0.050    17 ;NA
   C8    opls_353   0.340    18 ;CK
   H8    opls_359   0.120    19 ;H5
   N7    opls_352  -0.710    20 ;NB
   C5    opls_350   0.280    21 ;CB
   C6    opls_351   0.460    22 ;CA
   N6    opls_356  -0.770    23 ;N2
  H61    opls_357   0.380    24 ;H
  H62    opls_358   0.380    25 ;H
   N1    opls_346  -0.740    26 ;NC
   C2    opls_347   0.500    27 ;CQ
   H2    opls_355   0.130    28 ;H5
   N3    opls_348  -0.750    29 ;NC
   C4    opls_349   0.430    30 ;CB
  C2'    opls_158   0.140    31 ;CT
 H2''    opls_156   0.090    32 ;HC
  O2'    opls_171  -0.660    33 ;OH
  H2'    opls_172   0.430    34 ;HO
  C3'    opls_158   0.140    35 ;CT
  H3'    opls_156   0.090    36 ;HC
  O3'    opls_171  -0.660    37 ;OS
  H3T    opls_172   0.430    38
[ bonds ]
  PB    O3A
  PB    O1B
  PB    O2B
  PB    O3B
 O3A     PA
  PA    O1A
  PA    O2A
  PA    O5'
 O3'    H3T
 O5'    C5'
 C5'    C4'
 C4'    O4'
 C4'    C3'
 O4'    C1'
 C1'     N9
 C1'    C2'
  N9     C4
  N9     C8
  C4     N3
  C2     N1
  C6     N6
  N6    H61
  N6    H62
  C6     C5
  C5     N7
 C2'    C3'
 C2'    O2'
 O2'    H2'
 C3'    O3'
 C1'    H1'
 C2'   H2''
 C3'    H3'
 C4'    H4'
 C5'    H5'
 C5'   H5''
  C8     H8
  C2     H2
  N1     C6
  N3     C2
  C4     C5
  N7     C8
===============================
===============================
In the ffoplsaabon.itp file, I added:
; copied from ffoplsaanr
[ angletypes ]
 NA     CT     OS      1   109.500    418.680   ; DNA DCY
[ dihedraltypes ]
; these are again copied from ffoplsaanr
NA C CM CT 3 30.35430 0.00000 -30.35430 0.00000 0.00000 0.00000 ; aromatic ring DNA DTH C CM CT HC 3 -0.77874 -2.33623 0.00000 3.11498 0.00000 0.00000 ; aromatic ring DNA DTH HC CT CT NA 3 0.97134 2.91401 0.00000 -3.88535 0.00000 0.00000 ; RNA NA CT CT OH 3 16.74720 -16.74720 0.00000 0.00000 0.00000 0.00000 ; RNA CM NA CT OS 3 -3.14010 -3.14010 6.28020 0.00000 0.00000 0.00000 ; DNA DCY C NA CT OS 3 -3.14010 -3.14010 6.28020 0.00000 0.00000 0.00000 ; DNA DCY CT OS CT NA 3 -5.23350 7.32690 6.28020 -8.37360 0.00000 0.00000 ; [ dihedraltypes ]
; copied from charmm
 O2   P    OS  P  1   0.0       0.1255    3.0
 O2   P    OS  P  1   0.0       0.4184    2.0
 OS   P    OS  P  1   0.0       0.1255    3.0
 OS   P    OS  P  1   0.0       0.1255    2.0
===============================
On Jun 22, 2010, at 5:07 AM, Efrat Noy wrote:
Hi,
Does anyone have OPLS-AA topologies for ATP?
Thanks, Efrat
--
gmx-users mailing list gmx-users@gromacs.org <mailto:gmx-users@gromacs.org >
http://lists.gromacs.org/mailman/listinfo/gmx-users
Please search the archive at http://www.gromacs.org/search before posting! Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org <mailto:gmx-users-requ...@gromacs.org >.
Can't post? Read http://www.gromacs.org/mailing_lists/users.php

--
Dr Thomas Piggot
University of Southampton, UK.
--
gmx-users mailing list    gmx-users@gromacs.org
http://lists.gromacs.org/mailman/listinfo/gmx-users
Please search the archive at http://www.gromacs.org/search before posting! Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org.
Can't post? Read http://www.gromacs.org/mailing_lists/users.php

--
gmx-users mailing list    gmx-users@gromacs.org
http://lists.gromacs.org/mailman/listinfo/gmx-users
Please search the archive at http://www.gromacs.org/search before posting!
Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org.
Can't post? Read http://www.gromacs.org/mailing_lists/users.php

Reply via email to