MolDiA Tutorial



    Table of contents

    1. Description
    2. Computing Sim/Div using the Wizard Tutorial
    3. Computing Sim/Div using the Quick Analysis Tutorial
    4. Advanced Features
        4.1. Custom structural weights
        4.2. Custom property weights
    5. Menus
        5.1 Menu File
        5.2 Menu Options
        5.3 Menu Help

    Author: Ana Maldonado

    For a full description of MolDia click here   |   Download this tutorial here   |   Come back to Ana Maldonado's webpage


    Last updated on Monday, February 26, 2007

    Creative Commons License
    Some Rights Reserved
    This work is licensed under a Creative Commons Attribution- Noncommercial-No Derivative Works 2.0 France License.


    1. Description

    MolDiA (Molecular Diversity Analysis) is a chemoinformatic program which allows computing different similarity and diversity indices between molecular files on a MOL format. These indices will help you to rank, select and classify group of molecules in an quick and automatic way. Customization of the analysis is possible using a complete weight system included in the software.
    For a complete description about MolDiA click here.




    2. Computing Sim/Div using the Wizard Tutorial

    Once MolDiA software is installed following the steps of the setup provided, execution of the software will display the following Menu which contains the software main computation options.

    Menu

    To access the Wizard Beginners Tutorial, go to the menu File | Wizard. The Welcome window (WINDOW W0) gives a brief description of the software goals and the molecular format required.

    WINDOW W0
    WINDOW W0

    Then the WINDOW W1 is displayed. To effectuate the computation, it is possible to choose between two kind of analysis:
    - The "S" analysis allows the comparison between molecules only in function of their 2D structure. Structural descriptors will be constructed and the similarity computation will depend on the common substructures between the molecule query and test.
    - The "SP" analysis allows the comparison between molecules in function of the structure and the physicochemical properties. The dual descriptors constructed will allow a more complex comparison between the molecules analyzed. It is possible to choose only one option.

    WINDOW W1
    WINDOW W1

    To personalize the analysis it is possible to use the custom options. The structural and physicochemical information belonging to the molecular descriptors contain inherent weights. The customization of the structural weights is done by means of the WINDOW W2-1, in this window a list of meta-structures is proposed. It is posible to ignore the structure setting the weight to zero, or to increase their contribution by setting the weight to two. Default values are the same for all the structures and are automatically set to one. The customization of the physicochemical property weights is done by means of the WINDOW W2-2. In this window a limited set of properties and characteristics is proposed to be customized. The same procedure described before is applied to set the property weights. For more details about the custom screens go to the Advanced Features section of this tutorial.

    WINDOW W2-1 WINDOW W2-2
    WINDOW W2-1 and WINDOW W2-2

    Once the kind of analysis is chosen and the structural and property weights modified (or not), we access to the WINDOW W3 which gives the cardinality of the comparison.

    Four posibilities are given:
    - The 1-1 Analysis, which compute a similarity comparison between two molecules called "the query" and "the test".
    - The 1-N Analysis, which compute a similarity comparison between one query molecule and a group of N test molecules.
    - The N-N Analysis, where a diversity measure is computed between all the N molecules of a database (all the molecules will act as the query structure alternately).
    - The N-M Analysis, where a diversity measure is computed between all the N molecules of a query database and all the M molecules of a test database.

    WINDOW W3
    WINDOW W3

    Once the choice is done, we can upload the molecular files to be analyzed, as shown on WINDOW W4-1 and W4-2. Only MOL files will be displayed. Pay attention to the number of query molecules, which could be restricted in the 1-1 and 1-N analysis. The right and left arrows easy the copy of molecules from one window to another.

    WINDOW W4-1 WINDOW W4-2
    WINDOW W4-1 and WINDOW W4-2

    The next step is the molecular analysis which can be run from WINDOW W5. On a first moment the tool extracts and load the molecular informations of query and test molecules on the interface. Then comes the time-consuming step, which is the construction of the descriptors for the computation of similarity or diversity between the molecules loaded.
    Computation times, will depend of the number, size and complexity of the molecules to be analyzed.

    WINDOW W5
    WINDOW W5

    When the computation is finished, the "See Results" button will appear and gives access to the WINDOW W6. This window will allow the customization of the final computation and presentation of similarity or diversity indices.

    Three diferent indices (Tanimoto, Sympson and Cosine) can be computed simultaneously or individually. It is also possible to choose to show or not the descriptor vector of the analyzed molecules.

    The final results will be presented in form of hyperlinks which will give access to the XML result files.

    WINDOW W6
    WINDOW W6

    To open the XML result or descriptor-vector files, it is posible to use a text or XML editor. The XML files can be also saved as TXT files or imported using Excel or other tool for posterior treatment and analysis (ranking, plotting, statistics, etc). To visualize the content of the XML file it is enough to open the file in a web browser (e.g. IE). The automatic visualization of the file is assured by the presence of a XSL file. This file is automically copied to the results directory and allow the user to visualize the molecules and the informations computed by MolDiA in a clear and easy way.

    Some visualization requirements:
    - To ensure the molecular visualization when loading the XML file on a web browser it is necesary to have the MDL Chime plugin, as well as the JMOL JAVA engine.
    - To avoid "broken links" of the molecular information inside the result files is important to assure that the molecules which have been part of the calculus will remain at their original localisation. The absence of the molecular files can generate an error message of the MDL Chime plugin or JMOL applet in IE which will avoid visualisation of the file.

    A brief survey of some results files (WINDOW W7-2 and WINDOW W7-3) as well as descriptor-vector files (WINDOW W7-1), visualized using Internet Explorer 7.0 is given below.

    WINDOW W7-1, W7-2, W7-3
    WINDOW W7-1, WINDOW W7-2 and WINDOW W7-3




    3. Computing Sim/Div using the Quick Analysis Tutorial

    To access the Quick analysis window, go to the menu File | Quick Analysis. This window (WINDOW Q1) is composed of different parts which allows the experienced user to make a quick choice of the kind and nature of the analysis and to load the molecules to be analyzed in a single screen. For more details about MolDiA computation options go to the Wizard Tutorial.

    WINDOW Q1
    WINDOW Q1


    To personalize the analysis it is possible to use the custom buttons. The structural and physicochemical information belonging to the molecular descriptors can be customized using inherent weights. The customization of the structural weights is done by means of the WINDOW Q2-1. The customization of the physicochemical property weights is done by means of the WINDOW Q2-2. For more details about MolDiA weights customization go to the Advanced Features section.

    WINDOW Q2-1 WINDOW Q2-2
    WINDOW Q2-1 and WINDOW Q2-2

    Once the choice is done, the molecular files can be uploaded to be analyzed, as shown on WINDOW Q3-1 and Q3-2. Only MOL files will be displayed. The right and left arrows ease the transfer of molecules from one window to another.

    WINDOW Q3-1 WINDOW Q3-2
    WINDOW Q3-1 and WINDOW Q3-2

    The molecular analysis is run from WINDOW Q4. Computation times, will depend of the number, size and complexity of the molecules to be analyzed.

    WINDOW Q4
    WINDOW Q4

    When the computation is finished, the "See Results" button will appear and give access to the WINDOW Q5. This window will allow the customization of the final computation and presentation of similarity or diversity indices. The final results will be presented in form of hyperlinks which will give access to the XML result files.

    WINDOW Q5
    WINDOW Q5


    A brief survey of some results files (WINDOW Q6-2 and WINDOW Q6-3) as well as descriptor-vector files (WINDOW Q6-1), visualized using Internet Explorer 7.0 is given below. For more details about results visualization modalities and restrictions go to the Wizard Tutorial.

    WINDOW Q6-1, Q6-2, Q6-3
    WINDOW Q6-1, WINDOW Q6-2 and WINDOW Q6-3




    4. Advanced Features

    4.1 Custom structural weights

    To access the Custom structural weight WINDOW S1, go to the menu Options | Custom structural weights.
    The structural information belonging to the molecular descriptors can be customized using inherent weights.
    The WINDOW S1 propose a list of meta-structures which have been chosen after clusterization of the MolDiA FragDB. These structures are orderered on function of their size and complexity. First are presented some functional groups and then the small and big cyclic systems. Right to each structure the weight value is setted to one, two or zero.
    - Default values are the same for all the structures and are automatically set to one.
    - To ignore a particular structure when comparing molecules, set his weight to zero.
    - To increase the contribution of one or more structures, set their weight to two.

    WINDOW S1
    WINDOW S1

    Once the structural weights are modified, these informations will be kept in memory and will be used for all the future running analysis using the Wizard or the Quick Analysis tools. The weights can be changed at any moment of the calculus.

    4.2 Custom property weights

    To access the Custom property weight WINDOW P1, go to the menu Options | Custom property weights.
    The property information belonging to the molecular descriptors can be customized using inherent weights.
    Four caracteristics or physicochemical properties are posible to customize in the WINDOW S2. These properties have been chosen for their interest as parameter in molecular similarity and diversity computations. More features can be added in the future by defining computation rules which depend on the structure and caracteristics of fragments contained on the FragDB. The customization of the property weights is done by setting different values to the desired properties.
    - Default values are the same for all the properties and are automatically set to one.
    - To erase the effect of a particular property when comparing molecules, set his weight to zero. It is advised to do not use this option extensively, since multiple structures can be affected by setting a property weight to zero. If is desired to ignore the effect of multiple molecular caracteristics or properties, is preferable to effectuate a "S" type calculation (see WINDOW W1 of the Wizard tutorial) and avoid the use of property weights.
    - To increase the contribution of one or more properties, set their weight to two.

    WINDOW P1

    5. Menus

    5.1 Menu File

    This menu allows the user to effectuate a molecular sim/div computation following a simple wizard (recommended for beginners) or a quick analysis (for advanced users).

    MenuFile

    Menu Options:
    Wizard: allow access to the beginners tutorial.
    Quick Analysis : allow access to the advanced analysis window.
    Exit : close the program.

    5.1 Menu Options

    This menu allows the user to customize a molecular similarity/diversity computation.

    MenuOptions

    Menu Options:
    Custom Properties Weight : access to the Custom property weights
    Custom Fragment Weight : access to the Custom structural weights

    5.1 Menu Help

    This menu assists the user in the calculus and the customization of a molecular sim/div computation. It contains this tutorial, online information as well as complementary software information.

    MenuHelp

    Menu Options:
    MolDiA Help : access to this tutorial.
    MolDiA Online: access to complementary online MolDia information.
    About MolDiA : give information about software MolDiA throught the following window:

    AboutMolDiA







    Creative Commons License
    Some Rights Reserved
    This work is licensed under a Creative Commons Attribution- Noncommercial-No Derivative Works 2.0 France License.

    MolDiA software will be soon available under request.


    Download this document here