In molecular modeling and design, specifying chains efficiently can save significant time and effort. If you've ever wondered how to fine-tune your selection or manipulate chain-specific data in SAMSON's integrative molecular design platform, this guide to Chain Attributes will help you understand the power of the chain attribute space.
What are Chain Attributes?
Chain attributes in SAMSON reside within the chain attribute space (abbreviated as c). These attributes specifically address chain nodes and inherit properties from other attribute spaces like node and structuralGroup. With these attributes, you can query, filter, and affect chains in a highly granular manner based on various properties.
Commonly Used Chain Attributes
Let's explore some practical chain attributes and how they can be applied:
- Visibility Settings: Attributes like
visible (c.v),hidden (c.h), and their associated flags (visibilityFlag (c.vf)) allow you to manipulate the display of specific chains in your model. For example, usenot c.vto hide chains that are currently visible. - Material Properties: Check or filter chains based on their material attributes using
hasMaterial (c.hm)orownsMaterial (c.om). For instance,c.omwill select chains that own material.
Advanced Numerical Filtering with Structural Data
If your modeling work focuses on chain composition and structure, attributes inherited from the structuralGroup attribute space will be invaluable:
numberOfAtoms (c.nat): Use filters likec.nat < 1000to focus on chains with fewer than 1000 atoms.numberOfCarbons (c.nC),numberOfHydrogens (c.nH), andnumberOfOxygens (c.nO): Quickly pinpoint chains based on element-specific counts. For example,c.nC 10:20matches chains with 10 to 20 carbon atoms.numberOfCoarseGrainedAtoms (c.ncga): Ideal for coarse-grained models, you can select chains by atom range — say,c.ncga 100:200.
Specific Chain-Level Analysis
SAMSON provides chain-specific attributes beyond inherited properties to refine your molecular analysis even further. For example:
chainID (c.id): Seamlessly identify specific chains using their ID. Usec.id 1for a single chain or a range likec.id 2:4, 6to work with multiple chain IDs.numberOfResidues (c.nr): Apply filters to chains with specific residue counts. For example,c.nr > 130matches chains with more than 130 residues.numberOfSegments (c.ns): Focus on chains by segmentation, e.g.,c.ns < 3selects chains with fewer than 3 segments.numberOfStructuralGroups (c.nsg): Pinpoint chains based on their structural group count using filters likec.nsg > 10.
Conclusion
Mastering chain attributes in SAMSON is a powerful way to save time and enhance the precision of your molecular modeling work. Whether you're visualizing, analyzing, or filtering chains by specific properties, the platform's robust attribute system provides unmatched flexibility.
To explore more details about each of the chain attributes, including practical examples, visit the official documentation page here: https://documentation.samson-connect.net/users/latest/nsl/chain/.
SAMSON and all SAMSON Extensions are free for non-commercial use. Get SAMSON today at https://www.samson-connect.net.
