Data from: Modulating peptide co-assembly via macromolecular crowding: Recipes for co-assembled structures
Data files
Feb 27, 2025 version files 8.50 GB
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6K6E_DMD.tar.gz
246.65 MB
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crowder_DMD.tar.gz
8.25 GB
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README.md
13.30 KB
Abstract
Peptide-based biomaterials are commonly found in applications such as tissue engineering, wound healing, and drug delivery. Control over the size and morphology of the peptide supramolecular structure remains a challenge. One way to influence peptide assembly is through macromolecular crowding. Here we use discontinuous molecular dynamics simulation combined with the PRIME20 force field to investigate the effect of hydrophobic crowders on the architecture of co-assembled peptide aggregates. The peptide system used in this work is a mixture of oppositely-charged synthetic peptides: “CATCH(6K+)” (KQKFKFKFKQK) and “CATCH(6E-)” (EQEFEFEFEQE). The systems explored contained a mixture of 50 CATCH(6K+) and 50 CATCH (6E-) peptides at peptide concentrations of 5 mM and 20 mM, and crowders with diameters of 10, 20, 40 and 80 Å. Crowders were modeled as spheres with either hard-sphere or square-well/square-shoulder interactions. At low concentrations where CATCH co-assembly typically does not occur, the crowders were effective chaperones to trigger co-assembly. Small hard-sphere crowders promoted formation of multilayer fibrils. Large highly hydrophobic crowders promoted the formation of monolayer β-sheet structures and suppressed the formation of fibril structures. Overall, the simulations demonstrate that the crowder size and crowder-sidechain interaction strength govern the supramolecular architecture of peptide co-assemblies.
Modulating peptide co-assembly via macromolecular crowding: Recipes for co-assembled structures. Nanoscale
This directory contains the results from coarse-grained discontinuous molecular dynamics (PRIME20/DMD) simulations for the investigating the impact of macromolecular crowding on peptide co-assembly.
General overview of data included
Coordinate files from simulations are archived and compressed using tar and gzip.
| tarball name | description |
|---|---|
| 6K6E_DMD.tar.gz | contains results and files relating to PRIME20/DMD simulations for systems of CATCH(6K/6E) peptides in the absence of crowders |
| crowder_DMD.tar.gz | contains results and files relating to PRIME20/DMD simulations for systems of CATCH(6K/6E) peptides in the presence of crowders |
To preview the files within each tarball use the following command: tar -tf tarball.tar.gz. A file tree has been created for each tarball. These can be recreated using the tree command: tar -tf tarball.tar.gz | tree --fromfile ..
Additionally, a python script, read_bptnr.py, is included to open read files with a .bptnr extension. These files are described in the next section.
PRIME20 discontinuous molecular dynamics (DMD) simulations
PRIME20/DMD simulations produce two main files used for analysis: coordinate files with a .pdb file extensions, and data files specifying hydrogen bonding partners with a .bptnr file extension.
Coordinate files follow the standard Protein Data Bank file format.
Data files with a .bptnr extension contain information regarding hydrogen bonding partners. However, the very first file run0000.bptnr is empty as no assembly is present at the beginning of the simulation. Files that are generated during the simulation start at run0001.bptnr and contain a single column of integers. The first row corresponds to the collision number, the following rows corresponds to the index of the hydrogen bonding partner. As an example, consider the following snippet:
run0509.bptnr
100
30
62
...
In this data file, we are given the hydrogen bonding information for collision number 100. The 1st coarse-grained bead is hydrogen bonded to the 30th coarse-grained bead. The 2nd coarse-grained bead is hydrogen bonded to the 62nd coarse-grained bead, and so forth. Hydrogen bonding information is automatically calculated and outputed as part of the PRIME20/DMD software package.
6K6E_DMD.tar.gz
The 6K6E_DMD.tar.gz contains the final results relating to PRIME20/DMD simulations of systems containing CATCH(6K+) and (6E-) peptides. The directory names describe the system. For example, the directory "c05cr00-1": "c05" indicates a peptide concentration of 5 mM, "cr00" indicates no crowders are present, and "-1" is the simulation number (each system was simulated in triplicate).
Provided are the coordinate files (.pdb extension) and files indicating the hydrogen bonding partners (.bptnr extension). More information regarding the simulations are provided in the associated manuscript and on the Hall group's GitHub.
.
└── .
├── c05cr00-1
│ └── results
│ ├── run0000.bptnr
│ ├── run0001.bptnr
│ ├── run0001.pdb
│ ├── run0002.bptnr
│ ├── run0002.pdb
│ ├── run0003.bptnr
│ ├── run0003.pdb
│ ├── run0004.bptnr
│ ├── run0004.pdb
│ ├── run0005.bptnr
│ ├── run0005.pdb
│ ├── run0006.bptnr
│ ├── run0006.pdb
│ ├── run0007.bptnr
│ ├── run0007.pdb
│ ├── run0008.bptnr
│ ├── run0008.pdb
│ ├── run0009.bptnr
│ ├── run0009.pdb
│ ├── run0010.bptnr
│ ├── run0010.pdb
├── c05cr00-2
│ └── results
├── c05cr00-3
│ └── results
├── c20cr00-1
│ └── results
├── c20cr00-2
│ └── results
└── c20cr00-3
└── results
crowder_DMD.tar.gz
The crowder_DMD.tar.gz contains the final results relating to PRIME20/DMD simulations simulations of systems containing CATCH(6K+) and (6E-) peptides in the presence of crowders. The directory names describe the system. For example, the directory "c05cr10e00-1": "c05" indicates a peptide concentration of 5 mM, "cr10" indicates a crowder diameter of 10 Å, "e00" indicates a crowder-peptide interaction strength of 0ε (see manuscript for more detail), and "-1" is the simulation number (each system was simulated in triplicate).
Provided are the coordinate files (.pdb extension) and files indicating the hydrogen bonding partners (.bptnr extension). More information regarding the simulations are provided in the associated manuscript and on the Hall group's GitHub.
.
└── .
├── c05cr10e00-1
│ └── results
│ ├── run0000.bptnr
│ ├── run0001.bptnr
│ ├── run0001.pdb
│ ├── run0002.bptnr
│ ├── run0002.pdb
│ ├── run0003.bptnr
│ ├── run0003.pdb
│ ├── run0004.bptnr
│ ├── run0004.pdb
│ ├── run0005.bptnr
│ ├── run0005.pdb
│ ├── run0006.bptnr
│ ├── run0006.pdb
│ ├── run0007.bptnr
│ ├── run0007.pdb
│ ├── run0008.bptnr
│ ├── run0008.pdb
│ ├── run0009.bptnr
│ ├── run0009.pdb
│ ├── run0010.bptnr
│ ├── run0010.pdb
├── c05cr10e00-2
├── c05cr10e00-3
├── c05cr10e01-1
├── c05cr10e01-2
├── c05cr10e01-3
├── c05cr10e02-1
├── c05cr10e02-2
├── c05cr10e02-3
├── c05cr10e05-1
├── c05cr10e05-2
├── c05cr10e05-3
├── c05cr10ehf-1
├── c05cr10ehf-2
├── c05cr10ehf-3
├── c05cr20e00-1
├── c05cr20e00-2
├── c05cr20e00-3
├── c05cr20e01-1
├── c05cr20e01-2
├── c05cr20e01-3
├── c05cr20e02-1
├── c05cr20e02-2
├── c05cr20e02-3
├── c05cr20e05-1
├── c05cr20e05-2
├── c05cr20e05-3
├── c05cr20ehf-1
├── c05cr20ehf-2
├── c05cr20ehf-3
├── c05cr40e00-1
├── c05cr40e00-2
├── c05cr40e00-3
├── c05cr40e01-1
├── c05cr40e01-2
├── c05cr40e01-3
├── c05cr40e02-1
├── c05cr40e02-2
├── c05cr40e02-3
├── c05cr40e05-1
├── c05cr40e05-2
├── c05cr40e05-3
├── c05cr40ehf-1
├── c05cr40ehf-2
├── c05cr40ehf-3
├── c05cr80e00-1
├── c05cr80e00-2
├── c05cr80e00-3
├── c05cr80e01-1
├── c05cr80e01-2
├── c05cr80e01-3
├── c05cr80e02-1
├── c05cr80e02-2
├── c05cr80e02-3
├── c05cr80e05-1
├── c05cr80e05-2
├── c05cr80e05-3
├── c05cr80ehf-1
├── c05cr80ehf-2
├── c05cr80ehf-3
├── c20cr10e00-1
├── c20cr10e00-2
├── c20cr10e00-3
├── c20cr10e01-1
├── c20cr10e01-2
├── c20cr10e01-3
├── c20cr10e02-1
├── c20cr10e02-2
├── c20cr10e02-3
├── c20cr10e05-1
├── c20cr10e05-2
├── c20cr10e05-3
├── c20cr10ehf-1
├── c20cr10ehf-2
├── c20cr10ehf-3
├── c20cr20e00-1
├── c20cr20e00-2
├── c20cr20e00-3
├── c20cr20e01-1
├── c20cr20e01-2
├── c20cr20e01-3
├── c20cr20e02-1
├── c20cr20e02-2
├── c20cr20e02-3
├── c20cr20e05-1
├── c20cr20e05-2
├── c20cr20e05-3
├── c20cr20ehf-1
├── c20cr20ehf-2
├── c20cr20ehf-3
├── c20cr40e00-1
├── c20cr40e00-2
├── c20cr40e00-3
├── c20cr40e01-1
├── c20cr40e01-2
├── c20cr40e01-3
├── c20cr40e02-1
├── c20cr40e02-2
├── c20cr40e02-3
├── c20cr40e05-1
├── c20cr40e05-2
├── c20cr40e05-3
├── c20cr40ehf-1
├── c20cr40ehf-2
├── c20cr40ehf-3
├── c20cr80e00-1
├── c20cr80e00-2
├── c20cr80e00-3
├── c20cr80e01-1
├── c20cr80e01-2
├── c20cr80e01-3
├── c20cr80e02-1
├── c20cr80e02-2
├── c20cr80e02-3
├── c20cr80e05-1
├── c20cr80e05-2
├── c20cr80e05-3
├── c20cr80ehf-1
├── c20cr80ehf-2
└── c20cr80ehf-3
Usage Notes
Reading files with a .pdb extension
The .pdb files are human readable. The content of the .pdb files can be viewed with any text editor such as Sublime Text, Notepad++, TextEdit, etc. The .pdb file can also be loaded into a visualization software such as Visual Molecular Dynamics (VMD) or Chimera to produce a visual representation of the coordinates.
Reading files with a .bptnr extension
The .bptnr files are unformatted. These files can be read by using the format edit descriptor (i8,Ni4) where i8 is an integer that describes the collision number and N is the total of number of beads in the system. The format edit descriptor can be used to write a Fortran or Python program (using FortranFile) to read in the file.
A python script read_bptnr.py has been provided in this repository to aid in opening and reading these files. The script takes in two arguments: (1) the path of the .bptnr file to be read and (2) the total number of coarse-grained beads in the system.
Each system contains 100 CATCH peptides. Each peptide is represented by 44 coarse-grained beads. For considering only the peptides, this is a total of 4400 beads. Each crowder is represented by 1 coarse-grained bead. The number of crowders and total number of coarse-grained beads in each system considered is summarized in the table below.
| Peptide Concentration (mM) | Crowder Diameter (Å) | # of crowder beads | total # of beads |
|---|---|---|---|
| 5 | 10 | 12634 | 17034 |
| 20 | 1579 | 5979 | |
| 40 | 197 | 4597 | |
| 80 | 25 | 4425 | |
| 20 | 10 | 3148 | 7548 |
| 20 | 394 | 4794 | |
| 40 | 49 | 4449 | |
| 80 | 6 | 4406 |
The script returns the final hydrogen bonding partners in the snapshot. This information is represented using two columns of integers. The first column is the bead number. The second column is the hydrogen bonding partner. When the second column contains a value of 0, this indicates that the coarse-grained bead in the first column does not have a hydrogen bonding partner.
read_bptnr.py usage example
For example, to read the 'run0020.bptnr' from the simulation with the directory name c20cr10e00-1, we would use the following command
python read_bptnr.py run0020.bptnr 7548
This would return the following:
1 0
2 0
3 0
4 0
5 0
6 0
7 0
8 0
9 0
10 0
11 0
12 4123
13 3462
14 4121
15 3460
16 4119
17 3458
18 4117
19 3456
20 4115
21 0
22 0
23 4112
24 3451
25 4110
26 3449
27 4108
28 3447
...
The output indicates that beads 1-11, 21, and 22 do not have hydrogen bonds. While bead 12 is hydrogen bonding to bead 4123, and so forth.
