readFASTA: Read Protein Sequences in FASTA Format

Description Usage Arguments Value Author(s) References See Also Examples

View source: R/misc-01-readFASTA.R


This function reads protein sequences in FASTA format.


readFASTA(file = system.file("protseq/P00750.fasta", package = "protr"),
  legacy.mode = TRUE, seqonly = FALSE)



Path to the file containing the protein sequences in FASTA format. If it does not contain an absolute or relative path, the file name is relative to the current working directory, getwd. The default here is to read the P00750.fasta file which is present in the protseq directory of the protr package.


If set to TRUE, lines starting with a semicolon (;) are ignored. Default value is TRUE.


If set to TRUE, only sequences as returned without attempt to modify them or to get their names and annotations (execution time is divided approximately by a factor 3). Default value is FALSE.


Character vector of the protein sequences.

The three returned argument are just different forms of the same output. If one is interested in a Mahalanobis metric over the original data space, the first argument is all she/he needs. If a transformation into another space (where one can use the Euclidean metric) is preferred, the second returned argument is sufficient. Using A and B is equivalent in the following sense.


Nan Xiao <>


Pearson, W.R. and Lipman, D.J. (1988) Improved tools for biological sequence comparison. Proceedings of the National Academy of Sciences of the United States of America, 85: 2444–2448.

See Also

See getUniProt for retrieving protein sequences from


P00750 = readFASTA(system.file("protseq/P00750.fasta", package = "protr"))

Example output

protr documentation built on Nov. 22, 2018, 9:04 a.m.