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bio3d (version 2.3-4)

aa.index: AAindex: Amino Acid Index Database

Description

A collection of published indices, or scales, of numerous physicochemical and biological properties of the 20 standard aminoacids (Release 9.1, August 2006).

Usage

data(aa.index)

Arguments

Format

A list of 544 named indeces each with the following components:

  1. H character vector: Accession number.

  2. D character vector: Data description.

  3. R character vector: LITDB entry number.

  4. A character vector: Author(s).

  5. T character vector: Title of the article.

  6. J character vector: Journal reference.

  7. C named numeric vector: Correlation coefficients of similar indeces (with coefficients of 0.8/-0.8 or more/less). The correlation coefficient is calculated with zeros filled for missing values.

  8. I named numeric vector: Amino acid index data.

References

Grant, B.J. et al. (2006) Bioinformatics 22, 2695--2696.

‘AAIndex’ is the work of Kanehisa and co-workers: Kawashima and Kanehisa (2000) Nucleic Acids Res. 28, 374; Tomii and Kanehisa (1996) Protein Eng. 9, 27--36; Nakai, Kidera and Kanehisa (1988) Protein Eng. 2, 93--100.

Examples

Run this code
# NOT RUN {
## Load AAindex data
data(aa.index)

## Find all indeces described as "volume"
ind <- which(sapply(aa.index, function(x)
                    length(grep("volume", x$D, ignore.case=TRUE)) != 0))

## find all indeces with author "Kyte"
ind <- which(sapply(aa.index, function(x) length(grep("Kyte", x$A)) != 0))

## examine the index
aa.index[[ind]]$I

## find indeces which correlate with it
all.ind <- names(which(Mod(aa.index[[ind]]$C) >= 0.88))

## examine them all
sapply(all.ind, function (x) aa.index[[x]]$I)
# }

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