Release Notes v1.42d

The User Guide has also been rewritten for this release.

THINK v1.42d

KNIME

KNIME (pronounced naim) provides a means of visualising and configuring the steps for a molecular modelling study where each step has a pictorial representation as a node in a workflow. More information can be found here.

THINK 1.42 allows optional inputs to be used in place of files for Search, Similarity, R-group and Docking nodes. In addition, it is now only necessary to connect those inputs of the Enumeration node which correspond to R-groups which are to be used in the enumeration.

THINK 1.42c is compatible with KNIME 2.2.0 and does not work with earlier releases.

Note: It is necessary the define the environment variables THINK_EXEC and THINK_WORKING for the paths to the THINK software folder and a working folder. Different users may have different working folders. Without these definitions KNIME does not know the location of the THINK software or where to write temporary files for THINK.

De Novo

The 3D De Novo capabilities have been enhanced to allow docked fragments to grow into larger drug-like molecules. In this case, larger increases in the number of non-hydrogens atoms can be enabled by setting the CURB value. The transformation probability is progressively decreased for transformation which insert more than this number of non-hydrogen atoms to reach zero at twice the curb value.

Enhancements to Display

Orientate

The 3D display functionality has been enhanced by functionality which allows molecules to be orientated to view along a bond, a vector (line between 2 atoms) and onto a plane. The Orientate item is found on the right mouse button popup.

Superimpose

The ability to fit molecules together by matching pairs of atoms is now available from 3D display. The Superimpose item is found as a subitem to Orientate on the right mouse button popup. The functionality to manipulate a fragment independently of other fragments has also been included. Use the Global motion item on the right mouse button popup to switch between global motion and that of a selected fragment.

Atom selection

The select and highlight atoms has been extended to use modifier keys which are pressed at the same time as the mouse is clicked to allow:  
SelectClickModifier key
AtomAtom 
MoleculeAtomTAB
FragmentAtom then
Same atom

SHIFT
PathFirst atom then
Second atom

SHIFT
Bond/ChainBond
Atoms in sphereClick atom drag
then Release
 
Atoms in rectangleClick drag
then Release
 
Invert selection CTRL with above

These capabilities can be used with the new Edit Group found on the right mouse button popup. Select the group number to which atoms are to be set then select the atoms (which will be highlighted). This functionality is useful when the 3D De Novo capabilities are used for controlling which parts of docked fragments grow into molecules.

Bridged rings

Coordinates for most bridged rings can now be generated (2D and 3D) and adequately displayed.

Other Changes

2D Edit

There have been some improvements to 2D Edit including:

Transformations

In most cases, it is no longer essential to use explicit hydrogens in De Novo transformations as these will be added with the appropriate group numbers automatically. When saving transformations using text commands a new option TRANSFORMS forces hydrogens to be included and converts atom type 0-9 for connections to A.

Lipophilic centres

The functionality to create interaction centres for binding sites has been extended to include the creation of lipophilic centres.

Bug fixes

The annealing step in the De Novo derivative 2D mode was inadvertently disabled in THINK 1.42c. This has been re-enabled in THINK 1.42d except for 3D mode. A problem concerning atoms with high serial numbers (>1000) causing derivatives to be rejected with the condition "too many generations" has also been eliminated.

SERVER v1.42

There are no software changes.

Release Notes v1.41d

THINK v1.41d

KNIME

KNIME (pronounced naim) provides a means of visualising and configuring the steps for a molecular modelling study where each step has a pictorial representation as a node in a workflow. More information can be found here.

THINK 1.41 has two additional nodes to allow focused and diverse subsets of molecules to be selected based on the pharmacophores they exhibit compared to a reference set. The pharmacophore node has been enhanced by to allow the pharmacophore profile for a set of molecules to be an additional output. A focused selection has overlapping pharmacophores with this reference set whereas a diverse selection has non-overlapping pharmacophores. The minimum number of overlapping or non-overlapping pharmacophores may be configured.

WorkflowConfiguration WorkflowConfiguration
Show dialog FocusedSet node Show dialog DiverseSet node

The De Novo node has also been enhanced to provide 3D De Novo capabilities.

Demonstration videos of the main new capabilities are available.

Focused subset
3D De Novo

THINK 1.4.1 is compatible with KNIME 1.3.3.

Note: It is necessary the define the environment variables THINK_EXEC and THINK_WORKING for the paths to the THINK software folder and a working folder. Different users may have different working folders. Without these definitions KNIME does not know the location of the THINK software or where to write temporary files for THINK.

3D De Novo

The De Novo structure generation has been enhanced to modify/add 3D substituents to a molecule which has been previously docked into a protein site. Only transformations with one connection position are used whereas 2D De Novo derivative transformations may have multiple connection positions. This development requires the protein to be present in order to constrain the derivatives (and their conformations) in order to fit within the binding site. If derivatives of the known ligand from a PDB file are required, then this ligand can be extracted and saved (output 3 from the FindSites node) for subsequent use with the Docking node.

WorkflowConfiguration
Show dialog De Novo node
CommandsDialogs
SUGGEST MOLECULE=#1 MAXIMUM=100 TIME=1000 OUTPUT=more.sdf SITE=1FGI 3D De Novo is not supported

The 3D De Novo functionality may also be used with a pharmacophore volume constraint map. When using KNIME these can be generated by selecting the appropriate mode in the Pharmacophore node, using the Search node to orientate the molecule inside the constraint map and the corresponding mode in the De Novo node to use the map as a constraint.

WorkflowConfiguration
Show dialog De Novo node
Show configuration dialog

Note: There have been changes to the transformation file (tranform.smi) which may result in different 2D derivatives being generated than earlier releases.

Enhancements to Display

Map on/off

The map display visbility can now be toggled on the right mouse button pop-up menu without returning to the configuration dialog. This is especially useful when using a KNIME workflow.

Scroll Bar

The 3D display with a display panel has been enhanced by the addition of a scroll bar on the main graphics window. For a series of docked molecules/poses, this allows users to scroll between them without clicking on the Display Panel to swap visibility.

Mouse Sensitivity

The sensitivity of the mouse movement for scaling and clipping has been reduced.

Other Changes

Residue Connectivity

If the connectivity of a non-standard residue is omitted in a PDB file, THINK will now attempt to generate the connectivity (as well as the bond order).

CSV output

CSV output files will no longer contain fields which have not been populated or previously referenced/defined.

Implicit Hydrogens

The use and definition of added (ie implicit) hydrogens has been improved with the consequence that they are no longer included in MACCS SD 2D files which are subsequently written. (This was important for R-group searching and enumeration).

SERVER v1.41

There are no software changes.

Release Notes v1.40h

THINK v1.40h

KNIME

KNIME (pronounced naim) provides a means of visualising and configuring the steps for a molecular modelling study where each step has a pictorial representation as a node in a workflow. Using workflows for computer aided chemistry is both easier and more intuitive than traditional GUI and command scripts. Workflow technology is well established in the pharmaceutical industry for ChemInformatics applications usually processing 2D information, for instance to select subsets of commercial catalogues.

Demonstration videos of the main capabilities are available.

2D functionality
Structure-based virtual screening
Pharmacophore tools

KNIME is also used by some other vendors of computational chemistry software and provides a platform for integrating functionality provided by vendors as well as developed in-house. KNIME also includes a wide-range of statistical tools. The automation of KNIME facilitates exploring more possibilities such as alternative binding sites and reporting the performance of different possibilities in concise tabular forms.

Note: It is necessary the define the environment variables THINK_EXEC and THINK_WORKING for the paths to the THINK software folder and a working folder. Different users may have different working folders. Without these definitions KNIME does not know the location of the THINK software or where to write temporary files for THINK.

Site Searches

Water

In previous releases, water molecules could be included in the protein molecule associated with a site query. These molecules are ignored if they overlap with ligand atoms. Water molecules which are present in the binding site and interact with a ligand used to create the query are now automatically placed and saved in the protein molecule. This eliminates adding these waters by manually editing the PDB file.

Centre Positions

When creating a site query using a docked ligand, it was possible that the interaction centre positions were not appropriate for reproducing a known interaction such as a hydrogen bond. If the distance between the relevant ligand atom and the nearest interaction centre is greater than the tolerance an additional interaction centre is now placed at the coordinates of the ligand atom. There have also been some small changes to the interaction centre positioning including increasing the separation of aromatic centres from the defining ring to 3.7Å and the number of centres and their positions for water molecules.

Other Changes

List Distances

A command and dialog item has been added to allow distances to be listed. When used to list interaction distances between a ligand and a protein it is necessary to specify the molecules and desirable to specify a distance range to limit the size of the listing.

CommandsDialogs
LIST INFO=DISTANCES SELECT=^2CHM,^#3,0,4 List distances is not supported
LIST INFO=DISTANCES SELECT=^2CHM,"^CHM-METAL",0,4

SD files without hydrogens

An option has been added to omit hydrogens from SD files. In previous releases 3D SD files always included hydrogens while 2D SD files do not.

CommandsDialogs
SAVE FILE=molecule.sdf OPTION=NOHYDROGEN Not supported from dialogs

Calculating Bond Orders

Functionality has been added to calculate bond orders retaining existing connections. This is used automatically when reading HET groups such as ligands from PDB files. The algorithm which is also used when computing connections has been improved to deduce aromaticity for planar rings.

CommandsDialogs
MODIFY MOLECULE=#1 REBUILD=BOND-ORDERS Not supported from dialogs

Pharmacophore volume and area

The pharmacophore area and volume checks during a site searches eliminate hits which exhibit the pharmacophore in a small fraction of the molecule. This can now be disabled by setting the volume/area to zero giving more hits.

CommandsDialogs
CUSTOM AREA=0. VOLUME=0. Not supported from dialogs

KNIME related changes

There have been a number of small changes which have improved the integration with KNIME and access to appropriate functionality:

Bug fixes

SERVER v1.40

There are no software changes.

Release Notes v1.32g

THINK v1.32g

Dialog help text

Help text is now available for all dialogs as tooltip help (in a popup box) for each item. The help text for all items on a dialog is also available online and accessed by clicking Menus on the Help menu.

Activity Dialog

An extra tab has been added to the Preferences dialog for specifying the activity field, activity type and significance (to identify the most active and most inactive molecules). When the activity type is specified the significance configuration is changed. The functionality to subdivide molecules into "most active" and "most inactive" has been revised to allow absolute values of activity to be specified.

CommandsDialogs
CUSTOM ACTIVITY=activity SIGNIFICANCE=4,8 ATTRIBUTES=HIGH Show dialog File > Preferences > Activity

Previously, a subset of these activity configuration controls were duplicate in part on several different dialogs. In command mode, it is now necessary to use the CUSTOMISE command rather than additional keywords to various other commands.

Pharmacophore Profiles

Profile Comparisons

Logical operations between a profile being read and on already in memory may now be performed. Common pharmacophores between the profiles for two sets of molecules may be identified using AND and different pharmacophores using the NOT keyword. Other logic keywords include ADD, NEW, OR and EOR.

CommandsDialogs
READ FILE=profile1.proProfile logical operations not supported
READ FILE=profile2.pro LOGIC=AND

Saving Pharmacophore Coordinates

The coordinates for the pharmacophores in a profile can now be stored in a file with the extension .phc. This change allows such files to be created without resorting to command scripts. It is usually adviseable to limit the number of pharmacophores written and/or specify a threshold on the pharmacophore population. The profile is ordered so that pharmacophores with the highest population are written first.

CommandsDialogs
CUSTOMISE PHARMACOPHORE=100 EMPTY=10 Show dialog File > Preferences > Pharmacophores
SAVE FILE=pharm_coords.phc molecule=* Show dialog File > Save As > Type: Pharmacophore coordinates

Please note: In general, it is advisable to specify the molecule=* option in command mode as otherwise an existing profile will be used to avoid unnecessary recalculation.

Activity Profiles

If the name of the field containing the activity and an activity threshold (with associated attributes) is defined, then the profile calculated is that for the active molecules is less that for the inactive molecules. In THINK 1.32g the profiles for the active and inactive molecules are normalised before subtraction.

CommandsDialogs
CUSTOM ACTIVITY=pactivity ATTRIBUTE=ABSOLUTE SIGNIFICANCE=6Not supported via preferences
SAVE FILE=profile1.pro molecule=*

Pharmacophore Profiling Performance

The performance of pharmacophore profiling has been improved by applying pharmacophore volume and accessibility tests to the pharmacophores. This reduces the number of small and irrelevant pharmacophores in the profile and significantly improves the performance by typically more than 10-fold.

If one or more molecules do not exhibit any pharmacophores, then a trace option can be used to report the reasons to the console. (The same trace mode is supported for 3D searches).

CommandsDialogs
LET #ITRACE=1025Not supported

Ligand Query Dialog

The steps necessary to create a Ligand Query Volume map from a set of active molecules and use this in 3D pharmacophore searches with volume constraints have been brought together in a single dialog. Previously it was necessary to perform the following tasks using different dialogs or hand written command scripts:

  1. Create the pharmacophore profile for the active molecules
  2. Perform a series of pharmacophore searches, saving the conformations from which the volume maps are created.
  3. Perform the required searches

The new dialog has the essential configuration options and 3 buttons to perform the tasks in sequence. The first step is invariably to specifiy the file containing the active molecules. Additional information about the calculations is written to a file with the same filename as the active molecules and the extension type .lis. In most cases it is advisable to limit the number of pharmacophores saved to around 100 and ensure that the validation percentage allows one of the active molecules not to be found. It is not unusual to increase the tolerance to 1.

CommandsDialogs
No command equivalent Show dialog Calculate > Ligand Query

If activity data is present in the molecule file, the activity field name, type and significant configured, then a difference pharmacophore profile will be calculated which can reduce the number of pharmacophores and maps which are created. When this file is used in the search step, then additional output reports how successful each volume map is at eliminating inactive molecules and future searches can be restricted to the most effective map constraint.

Known limitation: The file containing the active molecules must be in the current working folder. If this is not the case then the second step fails with a file not found message.

Site Searches

Scoring functions

A number of improvements have been made to the scoring function which are referred to as THINKScore 1.0 (abbreviated to TS1.0) which is used by default in preference to ChemScore 2.1 (abbreviated to CS2.1) which remains available. The most significant difference is the use of a Coulombic charge term for hydrogen bonding in preference to the ChemScore parameterised term.

CommandsDialogs
CUSTOM SCORE=CS2.1Only changed using commands

The constants used in the scoring function are in common variables (reported by LIST CUSTOMISE) and in some circumstances it may be appropriate to change these values using command scripts.

Side-Chain motion

A new option has been added to adjust the side-chain torsion angles of residues in the receptor site. In practice, this is a better alternative than using soft VdW interactions that allow false positives to fit. The necessary changes to the VdW terms of the scoring function and a switch to using a Steepest Descents (rather than Conjugate Gradient) minimiser is performed automatically when side-chain motion is enabled.

CommandsDialogs
SEARCH MODE=SITE FILE=1bqo-q1-tested.smi QUERY=1BQO-Q1 OPTION=SIDE-CHAIN Show dialog Search > 3D > Side-chains

Multiple Volume Map Search Constraints

THINK 1.32 has a subtle but important improvement when using volume map search constraints. Previously, it was only possible to use one volume map for each pharmacophore during the search although the code which generated these maps produced several alternative volume map constraint for each pharmacophore. If a single map is specified using the SITE keyword, then only that map is used in the search otherwise all ligand maps are used as search constraints. The consequence of this enhancement is that the time for performing searches with map constraints is significantly reduced because the need to perform multiple searches with the same pharmacophore is eliminated.

Conformational Generation

Molecules which are very flexible are often filtered out by "drug-likeness" criteria. However, on occasions it may preferred to use a sampling method for the more flexible molecules. THINK 1.32 can be configured to automatically swap from systematic conformation generation mode to sampling such molecules based on the number of rotating bonds or an estimate the number conformations which will be processed (ie the flexibility derived from the product of the number of sample points about each bond). This enhancement means that slightly more flexible molecules can be included pharmacophore profiles without excessive time penalties.

CommandsDialogs
CUSTOMISE TWIST=8 GENERATE=6561 SAMPLE=1000 Show dialog File > Preferences > Conformers

Other Changes

List Charges

A command and dialog item has been added to allow partial atomic charges to be listed (these are used by the THINK scoring function). The partial charges are calculated by the Skorcyzk method as this gives the best hydrogen bonding energies.

CommandsDialogs
LIST INFO=CHARGES MOLECULE=#1 Show dialog View > Atom Data > Data: Charges; List

Map Best Plane Projection

The ROTATE command has been extended to apply a global rotation to generate the best plane projection for a map. This orientates the map so that its longest inertial axis is along the X-axis (horizontal) and shortest axis is along the Z-axis (out of the screen). Similar functionality exists for a molecule or list of atoms.

CommandsDialogs
ROTATE TOMAP=mapnameNot available from dialogs

Script Progress Reports

When executing a command script, an extended progress dialog is now displayed which includes the file name of the script and the fraction of the file processed. The default description can be overridden using the symbol DESCRIPTION and the default fraction complete can be overridden using the symbol PROGRESS. The default behaviour may be restored with the value FILE (or undefined) and the progress dialog omitted if the DESCRIPTION value is set to OMIT.

Bug fixes

The THINK interpreter gave priority to add before subtract in arithmetic expression which does not give the intuitive results. Priority is now given to subtract!

An obscure precision problem affected some Boltzman population pharmacophore profiles, when the populations and the denominator (or partition function) was not computed with sufficient precision. In THINK 1.32 relative energies are used for calculating the exponent term and the base energy value is reset during the calculation when appropriate.

In pharmacophore profiles, the maximum population of a bin is now 100% regardless of redundant populations (when one conformation exhibits the a pharmacophore more than once).

SERVER v1.32

There are no software changes.

Release Notes v1.31

THINK v1.31

Map Display

The graphics capabilities have been enhanced by the ability to display and manipulate 3D VdW volume and electrostatic potential maps. Users may specify the level and colours of the contours and delete the maps when they are no longer required.

CommandsDialogsOutput
CALCULATE MAP=dopamine_VDW TYPE=VDW MOLECULE=dopamine Show dialog Calculate > Maps > Calculate
CUSTOM VDW=1.0,Magenta,0.99,BlueShow dialogFile > Preferences Contours 
DISPLAY MODE=3D STYLE=STICK MOLECULE=* MAP=dopamine_VDW Show dialog View > Molecule 3D Stick; Show Map:dopamine_VDW; Display Show map display
LIST INFO=MAPS SELECT=T11_* Show dialog View > Atom Data > Data: Maps; List
DELETE MAP=T11_* Show dialog Edit > Delete > Maps; Delete

Maps may also be saved to disk with the file type .map when they are written as a text file which can be read in on another occasion. It is important to appreciate that when a global viewing transformation is applied, the orientation of any map subsequently saved will be changed. This means that if molecules and maps are saved at different times with intervening transformations, they will not be aligned correctly when read back in!

CommandsDialogs
SAVE FILE=test2.map MAP=T11_* Show dialog File > Save As > Save As Type: Maps; File name: test2.map; Save

The current implementation does not include the ability to perform logical operations between maps such as Union (OR), Difference (XOR) etc

Active Volume Search Constraints

This major enhancement allows Site Searches to be performed without a model or crystal structure of the active site. In overview, a volume constraint which represents the known minimum volume of the binding cavity is automatically constructed from a set of known active molecules. The implementation uses a combination of the pharmacophore profiling capabilities and the 3D volume maps.

OPEN FILE=fgi-t.smi CUSTOM COUNT=POPULATION EMPTY=20 BEST=100 SAVE FILE=fgi-t.phc OPEN FILE=fgi-t.phc SEARCH MODE=3D FILE=fgi-t.smi OPTIONS=ALL QUERY=AADX-105066 OUTPUT=AADX-105066.sdf OPEN FILE=aadx-105066.sdf CALCULATE MAP=aadx-105066-ligand TYPE=LIGAND MOLECULES=@AADX-105066 SEARCH MODE=SITE QUERY=AADX-105066 FILE=collection.smi OUTPUT=selected.sdf SITE=AADX-105066_1

When the pharmacophore profile is exported with the file type .phc as a set of coordinates for each pharmacophore, it is sorted by population so that the most common pharmacophores across the set of active molecules are written first. When using dialogs, the pharmacophores are calculated and saved for all molecules using the current conformational generation and pharmacophore configurations. Occasionally, the population exceeds 100% which implies that at least one molecule exhibits that pharmacophore more than once in the same conformation. The pharmacophores are sorted in descending population count and it is often useful to truncate the number saved either by the ignoring counts below a threshold value (the empty value) or by processing the 'n' most common pharmacophores.

CommandsDialogs
CUSTOM COUNT=POPULATION EMPTY=10 PHARMACOPHORES=100 Show dialog File > Preferences Pharmacophores Profile:Boltzman Empty=10; Use best=100
SAVE FILE=actives.phc Show dialog File > Save As > Save As Type: Pharmacophore coordinates; File name: actives.phc; Save

The pharmacophores can be used immediately in a Site Search but in the absence of a volume constraint tend to give too many false positives. It is often necessary to increase the default tolerance (of 0.5) in order to validate that the set of molecules used to generate the pharmacophore, will be found in a Site Search using that pharmacophore. This is an inevitable consequence of the granularity of the bin model used to represent distances in the pharmacophore profile. There are usually a number of pharmacophores which occur sufficiently frequently to justify their use as search queries.

When a pharmacophore is used in a 3D Search, a set of conformations is generated which exhibit that query. These conformations are used to calculate a volume search constraint for that pharmacophore. The software will automatically select subsets of these conformations (one for each molecule) which exhibit the lowest union volumes and create a volume map for each subset and (by default) retain the best 10 alternative maps distinguished by numeric suffixes. If no molecules are specified, all molecules with conformation numbers are processed. Such ligand volume maps can be used as active volume search constraints analogously to the protein residues which constitute the active site.

CommandsDialogs
SEARCH MODE=3D QUERY=ADDX-115266 FILE=actives.smi OUTPUT=addx-115266.sdf OPTION=ALL-CONFORMERS Show dialog Search > File: actives.smi; Best Conformation:Off; Search
CALCULATE MAP=ADDX-115266-LIGAND TYPE=LIGAND Show dialog Calculate > Maps > Ligand; Map name: ADDX-115266-LIGAND; Calculate
SEARCH MODE=SITE QUERY=ADDX-115266 FILE=collection.smi OUTPUT=hits.sdf Show dialog Search > File: collection.smi; Site:On; Search

In a site search, if the name of the constraint map is omitted, the first active volume map present will be used although the first protein site will be used in preference if present.

Minor Graphics Enhancements

The 3D display manipulation has been enhanced to allow the clipping slab thickness to be adjusted using Y-motion of the mouse while holding down the TAB key.

SERVER v1.31

There are no software changes.

Release Notes v1.30

This file contains the release notes for THINK v1.30 and THINK SERVER v1.30.

THINK v1.30

Molecular Mechanics

Some molecular mechanics capabilities have been added. These include a Simplex geometry optimisation and the use of the molecular mechanics energy in pharmacophore profiling (see below). In general it is NOT recommended to optimise the geometry of the starting conformation of a molecule in a conformational search as this inevitably gives a bias to the conformations which are accepted. However, the geometries of strained rings are usually improved by a molecular mechanics geometry optimisation and then fixed during a conformer generation.

Command: MODIFY REBUILD=OPTIMISE MOLECULE=name
Dialog: Not available from dialogs

The molecular mechanics energy calculation use simple (Chem-X like) quadratic terms for bond length and angle cosine terms. The form and barrier constant of the torsion term depends on whether the bond is conjugated or not. A Lennard-Jones (12-6) term is used for non-bonding interactions. The constants were included in the parameters files of previous versions. The current implementation has no option to include a Coulombic energy term arising from partial charges.

Bond length kl(l-lo)2 Where l is the bond length, kl and lo are constants for each pair of atom types
Bond angle kc(c-co)2 Where c is the cosine of the angle, kc and co are constants for each atom type
Conjugated torsion Vc(1-cos2f) Where Vc is the conjugated torsion constant and f is the torsion angle
Non-conjugated torsion Vnc(1 + cos3f) Where Vnc is the non-conjugated torsion constant and f is the torsion angle
Non-bonding interactions e1e2(1/r12 - 2/r6) Where e1 and e2 are constants for the atom types and r is the distance between them

At present, the molecular mechanics energy cannot be reported for a single conformation of a molecule or included in the property table.

Reading PDB files

The PDB format does not explicitly support the division of its contents into molecules. There are usually several indicators which can be used to identify molecules but the process is prone to error because certain types of records (eg HETNAM and HETSYN) are used for both non-standard residues and non-protein molecules. A strict application of the molecule concept would also create a separate molecule every occurrence of water and make somewhat arbitray decisions (based on connectivity) about whether a residue chain should be a different molecule.

For greater convenience THINK 1.30 attemps to create the following molecules from a PDB file:

In addition, changes have been made to reading site and secondary structure records.
Command: OPEN FILE=filename CHAIN=SEPARATE
Dialog: Not available from dialogs

Under some circumstances it is still necessary to edit a PDB file manually and insert NAME records to indicate the start of each molecule. For instance, when certain water molecules which are present in the active site are essential for binding and need to be in the protein molecule or when residue chains need to be grouped into subsets and stored as molecules.

Protein Sites

The way in which the site definitions are stored has been changed and the site identifier is now included in the residue part of the atom specification following the sequence number and separated by a full stop eg _(123A.ST1). Any secondary structure assignment is also included after the chain identify and separated from it by a full stop. Some new keyword values have been added to the INFO parameter of the LIST verb.

SITES To list the protein binding sites
RESIDUES To list the residues specified using the SELECT keyword
ATOMS To list the atoms specified using the SELECT keyword

Command: LIST INFO=SITES
Dialog: View > Atom Data > Data : Sites, List

Pharmacophore Population Profiles

The original implementation of pharmacophore profiling counts pharmacophore occurrences without consideration of the population of the conformers in which the pharmacophore occurs. This has the potential to cause misleading comparisons of pharmacophore profiles. In addition, it is not apparent from the pharmacophore count the proportion of molecules that exhibit a pharmacophore.

Two new options have been added to the CUSTOMISE COUNT keyword in 1.30:

Command: CUSTOMISE COUNT=POPULATION
Dialog: File > Preferences > Pharmacophores > Pharmacophore Profile: Boltzman Population

Note: If a pharmacophore occurs more than once in a conformation, this can lead to the profile value exceeding 100%.

Additional functionality has been added to generate and write out the pharmacophore geometries in SD file format.

Command: SAVE FILE=filename OPTION=COORDINATES
Dialog: Not available from dialogs

The functionality to select a subset of diverse molecules has been extended to allow pharmacophores to be used. The minimum number of new pharmacophores is expressed in percentage points when using POPULATION or FRACTION count methods.

Command: SELECT FILE=filename OUTPUT=filename PHARMACOPHORES=n
Dialog: Calculate > Selection > Pharmacophores

Minor Search Enhancements

After some hardware failures or shutdowns without stopping THINK, the progress information saved in the checkpoint or restart file was not consistent with the contents of the results file. In 1.30, the contents of the results file takes priority over the restart file, thus avoiding omitting hits in the results file.

Minor Graphics Enhancements

The functionality of the Display Panel has been extended for proteins to include options to extend the current selection from typically one residue to the chain or site (if any) containing the original selection.

Bug fixes

A minor correction has been made to the Lipophilic and Bad Contact terms in the docking scoring function. This can sometimes change the number of hits given by a search.

In the Windows version, the 2D functional group keys were sometimes written out as a string of question marks instead of hex codes. This was due to a compiler error and has now been worked around.

Progress reports have been added to the clustering code.

Release Notes for THINK v1.25


Server v1.30

Multiple copies

The queue locking implementation has been enhanced to support multiple copies of the queue manager running at the same time. This allows a copy to be running to assign jobs at the same time as another copy is used to load more jobs etc.