different papers report differing sequences

VARIANT

authors report that sequence variants exist

description of sequence variants produced by alternative splicing

MUTAGEN

      ACETYLATION

      AMIDATION

      BLOCKED

      FORMYLATION

      GAMMA-CARBOXYGLUTAMIC
      ACID HYDROXYLATION

of asparagine, aspartic acid, proline or lysine

      METHYLATION

generally of lysine or arginine

      PHOSPHORYLATION

of serine, threonine, tyrosine, aspartic acid or histidine

N-terminal glutamate which has formed an internal cyclic lactam

generally of tyrosine

 LIPID

covalent binding of a lipidic moiety

     MYRISTATE

myristate group attached through an amide bond to the N-terminal glycine residue of the mature form of a protein or to an internal lysine residue

     PALMITATE

palmitate group attached through a thioether bond to a cysteine residue or through an ester bond to a serine or threonine residue

     FARNESYL

farnesyl group attached through a thioether bond to a cysteine residue

     GERANYL-GERANYL

geranyl-geranyl group attached through a thioether bond to a cysteine residue

     GPI-ANCHOR

glycosyl-phosphatidylinositol (GPI) group linked to the alpha-carboxyl group of the C-terminal residue of the mature form of a protein

      N-ACYL DIGLYCERIDE

N-terminal cysteine of the mature form of a prokaryotic lipoprotein with an amide-linked fatty acid and a glyceryl group to which two fatty acids are linked by ester linkages

DISULFID

disulfide bond; the ‘FROM’ and ‘TO’ endpoints represent the two residues which are linked by an intra-chain disulfide bond; if the ‘FROM’ and ‘TO’ endpoints are identical, the disulfide bond is an interchain one and the description field indicates the nature of the cross-link

THIOLEST

thiolester bond; the ‘FROM’ and ‘TO’ endpoints represent the two residues which are linked by the thiolester bond

THIOETH

thioether bond; the ‘FROM’ and ‘TO’ endpoints represent the two residues which are linked by the thioether bond

CARBOHYD

glycosylation site; the nature of the carbohydrate (if known) is given in the description field

METAL

binding site for a metal ion; the description field indicates the nature of the metal

BINDING

binding site for any chemical group (co-enzyme, prosthetic group, etc.); the chemical nature of the group is given in the description field

SIGNAL

extent of a signal sequence (prepeptide)

TRANSIT

extent of a transit peptide (mitochondrial, chloroplastic, or for a microbody)

PROPEP

extent of a propeptide

CHAIN

extent of a polypeptide chain in the mature protein

PEPTIDE

extent of a released active peptide

DOMAIN

extent of a domain of interest on the sequence; the nature of that domain is given in the description field

CA_BIND

extent of a calcium-binding region

DNA_BIND

extent of a DNA-binding region

NP_BIND

extent of a nucleotide phosphate binding region; the nature of the nucleotide phosphate is indicated in the description field

TRANSMEM

extent of a transmembrane region

ZN_FING

extent of a zinc finger region

SIMILAR

extent of a similarity with another protein sequence; precise information, relative to that sequence is given in the description field

REPEAT

extent of an internal sequence repetition

HELIX

secondary structure: Helices, for example, Alpha‑helix, 3(10) helix, or Pi‑helix

STRAND

secondary structure: Beta‑strand, for example, Hydrogen bonded beta‑strand, or Residue in an isolated beta‑bridge

TURN

secondary structure Turns, for example, H‑bonded turn (3‑turn, 4‑turn or 5‑turn)

ACT_SITE

amino acid(s) involved in the activity of an enzyme

SITE

any other interesting site on the sequence

INIT_MET

the sequence is known to start with an initiator methionine

NON_TER

the residue at an extremity of the sequence is not the terminal residue; if applied to position 1, this signifies that the first position is not the N-terminus of the complete molecule; if applied to the last position, it signifies that this position is not the C-terminus of the complete molecule; there is no description field for this key

NON_CONS

non consecutive residues; indicates that two residues in a sequence are not consecutive and that there are a number of unsequenced residues between them

UNSURE

uncertainties in the sequence; used to describe region(s) of a sequence for which the authors are unsure about the sequence assignment