The CATH Domall file describes domain boundaries for entries in the CATH database. All PDB chains in CATH that contain 1 or more domains have a CathDomall entry. Whole chain domains can be identified where the number of domains is 1 and the number of fragments is 0.
Column | Description |
---|---|
1 | Chain name (5 characters) |
2 | Number of domains (formatted 'D%02d') |
3 | Number of fragments (formatted 'F%02d') |
The formatting of a Cath Domall file is best explained using examples.
KEY: N = Number of segments C = Chain character I = Insert character/code ('-' indicates no insert character) S = Start PDB number E = End PDB number NR = number of residues (fragment information only)
1chmA D02 F00 1 A 2 - A 156 - 1 A 157 - A 402 - N |C S I C E I| N |C S I C E I| |<----Domain One---->|<-----Domain Two---->| |<--Segment One-->| |<--Segment One-->|
This translates to:
Domain | Chain | Start/Stop |
---|---|---|
1chmA01 | A | 2-156 |
1chmA02 | A | 157-402 |
1cnsA D02 F00 2 A 1 - A 87 - A 146 - A 243 - 1 A 88 - A 145 - N |C S I C E I| C S I C E I| N |C S I C E I| |<--------------Domain One------------->|<-----Domain Two---->| |<--Segment One-->|<---Segment Two-->| |<--Segment One-->|
This translates to:
Domain | Chain | Start/Stop |
---|---|---|
1cnsA01 | A | 1-87, 146-243 |
1cnsA02 | A | 88-145 |
Fragments are small regions of the protein chain that are not included in the domain definition. These residue ranges are tagged on the end of the segment information. The format is different from the segment range information.
1amg 0 D02 F01 1 0 1 - 0 360 - 1 0 362 - 0 417 - 0 361 - 0 361 - (1) N |C S I C E I| N |C S I C E I| C S I C E I NR| |<----Domain One---->|<-----Domain Two---->|<---Fragment One----->| |<--Segment One-->| |<--Segment One-->|
This translates to:
Domain | Chain | Start/Stop |
---|---|---|
1amg001 | A | 1-360 |
1amg002 | A | 362-417 |
Fragment = 361
1bcmA D02 F02 1 A 257 - A 487 - 1 A 492 - A 559 - A 488 - A 491 - (4) A 560 - A 560 - (1) N |C S I C E I| N |C S I C E I| C S I C E I NR| C S I C E I NR| |<----Domain One---->|<-----Domain Two---->|<---Fragment One----->|<---Fragment Two----->| |<--Segment One-->| |<--Segment One-->|
This translates to:
Domain | Chain | Start/Stop |
---|---|---|
1bcmA01 | A | 257-487 |
1bcmA02 | A | 492-559 |
Fragments = 488-491, 560