Bead model hydrodynamics: an in-depth comparison between GRPY and ZENO.

Area of Science:

• Biophysics
• Computational Biology
• Structural Biology

Background:

• Hydrodynamic properties like translational diffusion and intrinsic viscosity are crucial for validating macromolecular structures.
• Bead modeling is an efficient method for simulating biomacromolecules, incorporating hydration effects.
• GRPY and ZENO are computational tools for hydrodynamic calculations on bead models, each with distinct computational approaches.

Purpose of the Study:

• To conduct an in-depth comparison of the GRPY and ZENO programs for calculating hydrodynamic properties of biomacromolecules using bead models.
• To evaluate the performance and consistency of GRPY and ZENO against each other and other established methods like HYDROMULTIPOLE and BEST.
• To identify discrepancies between GRPY and ZENO and propose potential improvements for ZENO.

Main Methods:

• Utilized bead modeling to represent biomacromolecules at atomic or residue levels.
• Performed hydrodynamic calculations using the GRPY (Generalized Rotne-Prager-Yamakawa) and ZENO programs, both integrated within the US-SOMO suite.
• Compared results with other methods: HYDROMULTIPOLE (accurate, no overlaps) and BEST (boundary elements, extrapolation required).

Main Results:

• Systematic, albeit small (0.2-2%), differences were observed between GRPY and ZENO results, increasing with model size.
• GRPY demonstrated better agreement with HYDROMULTIPOLE and BEST compared to ZENO when applied to protein bead models.
• ZENO's computational efficiency is nearly independent of model size, unlike GRPY's N³ dependency.

Conclusions:

• GRPY and ZENO exhibit slight but systematic differences in hydrodynamic property calculations for protein bead models.
• GRPY shows better overall agreement with other advanced computational methods.
• A heuristic correction for ZENO is proposed to enhance its consistency with GRPY, pending further performance improvements.