blosum

Return a BLOSUM scoring matrix

Syntax

Matrix = blosum(Identity, 
                'PropertyName', PropertyValue...)
[Matrix, Matrixinfo] = blosum(N)

blosum(..., 'Extended', ExtendedValue)
blosum(..., 'Order', OrderValue)

Arguments

Identity

Percent identity level. Enter values from 30 to 90 in increments of 5, enter 62, or enter 100.

Extended

Property to control the listing of extended amino acid codes. Enter either true or false.

The default value is true.

Order

Property to specify the order amino acids are listed in the matrix. Enter a character string of legal amino acid characters. The length is 20 or 24 characters.

Description

Matrix = blosum(Identity, 'PropertyName', PropertyValue...) returns a BLOSUM (Blocks Substitution Matrix) matrix with a specified percent identity. The default ordering of the output includes the extended characters B, Z, X, and *.

A R N D C Q E G H I L K M F P S T W Y V B Z X *

blosum(..., 'Extended', ExtendedValue) if Extended is false, this function returns the scoring matrix for the standard 20 amino acids. Ordering of the output when Extended is false is

A R N D C Q E G H I L K M F P S T W Y V

blosum(..., 'Order', OrderValue) returns a BLOSUM matrix ordered by an amino acid sequence (OrderString).

[B, MatrixInfo] = blosum(Identity) returns a structure of information about a BLOSUM matrix with the fields Name, Scale, Entropy, ExpectedScore, HighestScore, LowestScore, and Order.

Examples

Return a BLOSUM matrix with a value of 50.

B50 = blosum(50)

Return a BLOSUM matrix with the amino acids in a specific order.

B75 = blosum(75,'Order','CSTPAGNDEQHRKMILVFYW')

See Also

Bioinformatics Toolbox functions nwalign, dayhoff, pam, gonnet, swalign


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