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profit |
Scores for the matches are calculated from the simple frequency matrix. It is the sum of scores at each position of the matrix.
A 'simple frequency matrix' is simply a count of the number of times any particular amino acid occurs at each position in the alignment used to create it. Simple frequency matrices are created using the program prophecy with the option '-type F' to create the correct type of matrix. The alignment should not have gaps in it.
The resulting matrix is moved to each position in the sequence(s) you are searching. At each position in the sequence, the frequencies of the amino acids or bases covered by the length of the matrix is read from the matrix. The sum of these frequencies at each position of the matrix is the score for that position of the sequence. If this score is above the threshold percentage of the maximum possible score for that matrix, then a hit is reported.
This is the ungapped aligned set of sequences used to make the matrix:
% more m.seq >one DEVGGEALGRLLVVYPWTQR >two DEVGREALGRLLVVYPWTQR >three DEVGGEALGRILVVYPWTQR >four DEVGGEAAGRVLVVYPWTQR% prophecy Creates matrices/profiles from multiple alignments Input sequence set: m.seq Profile type F : Frequency G : Gribskov H : Henikoff Select type [F]: Enter a name for the profile [mymatrix]: Enter threshold reporting percentage [75]: Output file [outfile.prophecy]:
Here is a sample session with profit
% profit Scan a sequence or database with a matrix or profile Profile or matrix file: ../../data/outfile.prophecy Input sequence(s): tsw:* Output file [outfile.profit]: |
Go to the input files for this example
Go to the output files for this example
Mandatory qualifiers: [-infile] infile Profile or matrix file [-sequence] seqall Sequence database USA [-outfile] outfile Output file name Optional qualifiers: (none) Advanced qualifiers: (none) General qualifiers: -help boolean Report command line options. More information on associated and general qualifiers can be found with -help -verbose |
Mandatory qualifiers | Allowed values | Default | |
---|---|---|---|
[-infile] (Parameter 1) |
Profile or matrix file | Input file | Required |
[-sequence] (Parameter 2) |
Sequence database USA | Readable sequence(s) | Required |
[-outfile] (Parameter 3) |
Output file name | Output file | <sequence>.profit |
Optional qualifiers | Allowed values | Default | |
(none) | |||
Advanced qualifiers | Allowed values | Default | |
(none) |
# Pure Frequency Matrix # Columns are amino acid counts A->Z # Rows are alignment positions 1->n Simple Name mymatrix Length 20 Maximum score 76 Thresh 75 Consensus DEVGGEALGRLLVVYPWTQR 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 2 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 |
# PROF scan using simple frequency matrix mymatrix # Scores >= threshold 75 (max score 76) # HBB_HUMAN 21 Percentage: 100 |
The ouput is a list of three columns.
The first column is the name of the matching sequence found.
The second is the start position in the sequence of the match.
The third column (after the word 'Percentage:') is the percentage of the
maximum possible score (sum of the highest value at each
position in the frequency matrix).
Program name | Description |
---|---|
prophecy | Creates matrices/profiles from multiple alignments |
prophet | Gapped alignment for profiles |