For molecular modelers, one common pain point is quickly and efficiently identifying specific molecules or subsets of molecules in large datasets. Whether you’re categorizing molecules by their atomic composition or visualizing subsets, the powerful molecule attribute space in the Node Specification Language (NSL) in SAMSON simplifies this process.
This blog post will guide you through key molecule attributes that can help streamline your molecular modeling workflow. These attributes can be used to match and manipulate molecules based on their properties, enabling you to solve otherwise time-consuming tasks effectively.
The Basics of Molecule Attributes
The molecule attribute space in NSL (with the short name mol) is designed specifically for molecule nodes. It allows you to identify molecules based on their properties such as the number of atoms, chains, structural groups, and more. Here are some key types of molecule attributes:
Attributes Inherited from Node and StructuralGroup
- Visibility Attributes: Attributes like
visible(v) andhidden(h) let you specify if a molecule is visible or hidden in the workspace. Examples include:mol.v(visible) ornot mol.h(not hidden). - Atomic Composition Attributes: Attributes such as
numberOfAtoms(mol.nat),numberOfCarbons(mol.nC), andnumberOfHydrogens(mol.nH) enable you to focus on molecules with specific atomic counts. For example,mol.nC < 10matches molecules containing less than 10 carbon atoms. - Charge-Related Attributes: Attributes like
formalCharge(mol.fc) andpartialCharge(mol.pc) make dealing with charged molecular groups straightforward. For instance, usemol.fc > 1to query molecules with a formal charge greater than 1.
Attributes Unique to Molecules
- Chain and Residue Attributes: Attributes such as
numberOfChains(mol.nc) andnumberOfResidues(mol.nr) help match molecules based on their biological structure. For example,mol.nc < 3will match molecules with fewer than 3 chains. - Structural Detail: Use attributes like
numberOfSegments(mol.ns) andnumberOfStructuralGroups(mol.nsg) for even more detailed molecular queries. For example,mol.nsg > 10matches molecules with more than 10 structural groups.
Practical Examples
If your project involves working with proteins or polymers, you might want to filter molecules with specific numbers of chains or residues. Here are a few practical examples of how these attributes work:
mol.nr > 130: Finds molecules with more than 130 residues.mol.nnc 10:20: Matches molecules with 10 to 20 carbon atoms.mol.ns 2:4: Selects molecules with segments numbering between 2 and 4.
Such filters enable you to focus on specific structures within your dataset without manually sorting through large numbers of molecules.
Why Use NSL for Molecular Queries?
Using NSL’s molecule attributes saves significant time and ensures precision in your modeling work. With this functionality, you can query highly specific molecule subsets in seconds, making your workflow efficient and error-free. Moreover, the short name versions of attributes (e.g., mol.n for name) simplify scripting and make the queries compact yet powerful.
Learn More
Interested in exploring all the molecule attributes and refining your molecular modeling workflow even further? Check out the detailed documentation at https://documentation.samson-connect.net/users/latest/nsl/molecule/.
Note: SAMSON and all SAMSON Extensions are free for non-commercial use. You can download SAMSON at https://www.samson-connect.net.
