Protein Community

Jmol/JSmol Community

• Community & users
• Communities: Crystal · Protein · Quantum Chemistry · Solid State · Folding@home
• List of users & their pages

This subcommunity is for Jmol users that use Jmol for display and analysis of protein structures. Please add on this page your favorite scripts etc. for displaying proteins in Jmol.

• Angel Herraez page
• Eric Martz: FirstGlance in Jmol is a simple tool for exploring the structure of any on-line macromolecular model. Protein Explorer exports molecular views into Jmol, see MolSlides.Org

Molecular surfaces

documentation and testing page

Secondary structure

Starting with versions 12.0.18 and 12.1.15, Jmol implements the DSSP algorithm for determination of secondary structure in proteins. This is accompanied by some changes in the defaults and some new commands.

When reading files

1. If the pdb or mmcif file contains HELIX/SHEET/TURN information: that information is respected in all Jmol versions. In new Jmol versions, pdb and mmcif readers also read helix types alpha, pi, and 3₁₀, and color them slightly differently (Jmol Colors).
2. If the pdb or mmcif file des not contain HELIX/SHEET/TURN information:
   • Old versions of Jmol used Ramachandran-angle based calculation.
   • New versions of Jmol use DSSP calculation.
3. In the case of alpha-carbon-only chains, all versions of Jmol use the method of Levitt and Greer (doi).
4. In new versions of Jmol the calculation based on Ramachandran angles is still available (see below).

Forced recalculation of structure

calculate structure

This command overwrites any secondary structure assignment with a new one:

• In old Jmol versions, calculated using the Ramachandran method.
• In new Jmol versions, calculated using the DSSP method.

Note that, intentionally, Jmol turns off all bioshapes when the calculate structure command is given. So, you will usually want to follow it with cartoons on or something of the sort.

New commands

• calculate structure ramachandran is available for forcing the old method of calculation (it may have some advantages in certain contexts). It can be shortened to calculate structure rama.
• calculate hBonds structure does DSSP determining hydrogen bonds only.
• set defaultStructureDSSP false will change the defaults of file load and calculate structure to use the Ramachandran method; by default, it is true and uses the DSSP method.
• set dsspCalculateHydrogenAlways false does DSSP enforcing the use of backbone amide H atoms present in the file; by default, it is true and does standard DSSP, ignoring all backbone amide H atoms present in the file and using rough approximations instead.
• show dssp displays a report of the DSSP calculation.
• set debug displays a verbose DSSP calculation.
• save structure s1 (for example) saves in memory the current structure assignment with the internal ID 's1' for later restoring.
• restore structure s1 restores the previously saved assignment.

Selection and coloring

• color structure now applies different shades of color to alpha, 3₁₀ and pi helices (Jmol Colors).

• select helix includes all 3 types of helices.
• select helixAlpha
• select helix310 (example: 2JC9.pdb)
• select helixPi (example: 2JC9.pdb after calculate structure)
• select substructure=7 matches DSSP "G", i.e. 3₁₀ helices, same as select helix310
• select substructure=8 matches DSSP "H", i.e. alpha helices, same as select helixAlpha
• select substructure=9 matches DSSP "I", i.e. pi helices, same as select helixPi

• label %[substructure] labels with the texts: helixalpha, helix310, helixpi, sheet, turn, none

• structure helixAlpha ....
• structure helix310 ....
• structure helixPi ....

Reference section

• W. Kabsch, C. Sander (1983) Dictionary of protein secondary structure: pattern recognition of hydrogen-bonded and geometrical features. Biopolymers 22: 2577-2637. doi:10.1002/bip.360221211
• DSSP Home Page: http://swift.cmbi.ru.nl/gv/dssp/

• M. Levitt, J. Greer (1977) Automatic identification of secondary structure in globular proteins. J. Mol. Biol. 114: 181-239. doi:10.1016/0022-2836(77)90207-8

• Codes for structure types:

	PDB code	SPSS code	Jmol codes substructure and name
right-handed alpha (default)	1	H	8 helixalpha █
right-handed omega	2
right-handed pi	3	G	7 helixpi █
right-handed gamma	4
right-handed 310	5	I	9 helix310 █
left-handed alpha	6
left-handed omega	7
left-handed gamma	8
27 ribbon/helix	9
polyproline	10
(beta) strand	0 first 1 parallel -1 antiparallel	E	2 sheet █
turn		T	1 turn █
isolated beta-bridge residue		B
bend		S
none (unstructured protein)		-	0 none █
DNA			4 dna █
RNA			5 rna █
carbohydrate			6 carbohydrate █
other*			-1 █

Helix types in PDB format: columns 39-40 of HELIX record, right-justified.

Strand sense in PDB format: columns 39-40 of SHEET record, right-justified.

(*) Other = not protein, not nucleic, not carbohydrate.

Contributors

AngelHerraez, Wayne Decatur, EricMartz, NicolasVervelle, Pimpim