For molecular modelers, working with side chains is an essential aspect of refining and analyzing biomolecular structures. The ability to efficiently query and manipulate side chain attributes can significantly enhance productivity, making the process of molecular design more seamless and accurate. In this post, we’ll explore the Side Chain Attributes available in SAMSON’s Node Specification Language (NSL) and highlight how they can be used to tackle common modeling challenges.
What are Side Chain Attributes?
Side chain attributes are part of SAMSON’s Node Specification Language and are housed within the sideChain attribute space (with a short name, s). These attributes specifically match side chain nodes, allowing you to target and interact with molecular side chains in a precise manner.
Why Side Chain Attributes Matter for Modelers
Molecular modelers often need to answer precise questions or apply filters to side chain properties. Examples include identifying hidden side chains, filtering by atom counts, or querying for specific formal charges. Without streamlined tools, this process can be tedious and prone to error. The NSL functionality in SAMSON eliminates this pain by offering short, logical queries that are easy to implement.
Key Attributes and Their Applications
Here are some of the most common side chain attributes, their short names, and examples of how they can be utilized:
| Attribute | Short Name | Example Use Case |
|---|---|---|
| hasMaterial | hm |
Check whether a side chain owns material using sc.hm. |
| name | n |
Quickly identify side chains by name with sc.n "A". |
| numberOfAtoms | nat |
Query all side chains with an atom count below 1000 using sc.nat < 1000. |
| partialCharge | pc |
Target side chains with specific charge values using sc.pc 1.5:2.0. |
How to Use Side Chain Attributes
- Select Hidden Side Chains: Use the
hiddenattribute (sc.h) to target side chains marked as hidden. This is particularly useful for visualization and cleanup tasks. - Query Specific Elements: Attributes like
numberOfCarbons(nC) andnumberOfNitrogens(nN) allow you to filter side chains containing specific atoms or ranges of atom counts. For example, you can usesc.nC 10:20for carbons. - Owned Materials: With
ownsMaterial(om), check ownership of materials by side chains to optimize hierarchy or perform detailed structural queries.
Putting It All Together
Side chain attributes streamline the process of focusing on relevant molecular sections, saving time and improving accuracy. By mastering the attributes and leveraging NSL’s concise syntax, modelers can customize their workflow to suit specific tasks. Whether searching for visibility states, iterating through atom counts, or targeting side chains with specific names, these tools bring clarity to molecular modeling pipelines.
Learn More
Interested in diving deeper into side chain attributes and their potential applications? Visit the official SAMSON documentation for detailed explanations, examples, and more.
Note: SAMSON and all SAMSON Extensions are free for non-commercial use. Get SAMSON here.