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MultiIdent

MultiIdent is a tool that allows the identification of proteins using pI, Mw, amino acid composition, sequence tag and peptide mass fingerprinting data. One or more species and a Swiss-Prot keyword can also be specified for the search.

The program first generates a list of best-matching Swiss-Prot and/or TrEMBL entries with amino acid composition, and then uses other protein parameters (e.g. protein pI, Mw, sequence tag, peptide mass data) to query this list and identify the protein of interest.

Instructions are available.

Please fill out the following form, then press the Perform button.

Your e-mail address: ?

Unknown Protein

Name of unknown protein: ?

pI: within pI range: ?

Mw: within Mw range (in percent): ?

Term from Swiss-Prot/TrEMBL OS or OC line:
(example: HOMO SAPIENS or VERTEBRATA) ?

Keyword from Swiss-Prot KW (keyword) line:
?

Amino Acid Composition - Constellation 2

Constellation 2: Ala, Ile, Pro, Val, Arg, Leu, Ser, Asx, Lys, Thr, Glx, Gly, Met, His, Phe and Tyr. (Asp+Asn=Asx; Gln+Glu=Glx; Cys and Trp are not considered)

Currently, MultiIdent first generates a list of best-matching proteins by amino acid composition. This list is then used for the sequence tag and peptide mass fingerprinting parts of the program. As such, amino acid composition data must be entered for the unknown protein.

Amino Acid Composition of Unknown Protein ?

Asx:  Glx:  Ser: in molar percent (example: 12.50)
His:  Gly:  Thr:
Ala:  Pro:  Tyr:
Arg:  Val:  Met:
Ile:  Leu:  Phe:
Lys:

Amino Acid Composition of Calibration Protein ?

Data for a calibration protein is optional.

Protein ID: (example: ALBU_BOVIN)

Asx: Glx: Ser: in molar percent (example: 6.30)

His: Gly: Thr: Ala: Pro: Tyr: Arg: Val: Met: Ile: Leu: Phe: Lys:

Generate list of best-matched proteins and
print top ranked proteins of them (<= number of proteins in list). ?

all fields! the search!

Sequence Tag

You may enter a tag which will be matched with the sequences. In this case, you can choose to display either the protein N- or C-terminus, or the (internal) subsequence of each protein matching the tag. Note that 'X' can be used as an unknown amino acid in your tag.

Tag: ?

Display the N-terminal sequence or the C-terminal sequence or the (internal) area of the protein that matches your tag. ?

Search for all possible tag permutations. ?

Peptide Mass Fingerprinting ?

With this option, the entered peptide masses are compared to the appropriate peptide masses of the best-matching proteins in the amino acid composition search.

All masses are [M+H]⁺ or [M]. ?

All peptide masses are average, or monoisotopic.

Enter a list of peptide masses (separated by spaces or newlines) that correspond to the unknown protein: ?

Select an enzyme: ?

Cysteines:

The peptide masses are: with all cysteines in reduced form.; with all cysteines treated with: ?

Methionine: oxidize all methionines. ?

and with a tolerance of +/- Dalton. ?

Results

Print the lists of ?

closest Swiss-Prot entries (in terms of AA composition, pI and Mw not considered) for selected species and keyword,
closest Swiss-Prot entries (in terms of AA composition, pI and Mw not considered) for selected keyword and all species,
closest Swiss-Prot entries for selected species and keyword, having pI and Mw values in the specified range,
closest TrEMBL entries (in terms of AA composition, pI and Mw not considered) for selected species,
closest TrEMBL entries (in terms of AA composition, pI and Mw not considered) for all species,
closest TrEMBL entries for selected species, having pI and Mw values in the specified range, and within that:
the AAComposition scores
the peptide mass fingerprinting scores and/or
the integrated scores for AAComposition and peptide mass fingerprinting.