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FASTA (.fasta, .fa, .fna, .fsa, .mpfa)

MIME type: chemical/seq-aa-fasta, chemical/seq-na-fasta
FASTA molecular biology format.
Standard format for storing and exchanging DNA and protein sequences.
Plain text format.
Stores nucleic acid or protein sequences as character strings.
Various conventions are in use to represent meta-information.
Developed in 1988 by William Pearson and David Lipman as part of the FASTA sequence-alignment software.
  • Import and Export support all common variants of the FASTA file format.
  • Import imports DNA or protein sequences from a FASTA file.
  • Export exports a sequence or a list of sequences to the FASTA format.
  • Import returns a list of strings representing the sequences stored in the file.
  • Export exports a character string representing a DNA sequence to FASTA.
  • Export exports multiple DNA sequences.
  • Import imports the specified element from a FASTA file.
  • Import imports multiple elements.
  • Export creates a FASTA file by treating expr as specifying element elem.
  • Export treats each as specifying the corresponding .
  • Export exports expr with the specified option elements taken to have the specified values.
  • Export uses rules to specify the elements to be exported.
  • See the reference pages for full general information on Import and Export.
"Elements"list of elements and options available in this file
"Rules"full list of rules for each element and option
"Options"list of rules for options, properties, and settings
  • Data representation elements:
"Header"raw header lines
"Sequence"DNA or protein sequences as a list of strings
"Plaintext"sequences as formatted text
  • Import uses the element by default for the FASTA format.
  • Additional data elements:
"Data" and elements combined in a list
"LabeledData"list of rules for each sequence stored in the file
  • Header line meta-information:
"Accession"NCBI accession number for each sequence
"Description"locus description text for each sequence
"GenBankID"GenBank database identifier
"Length"list of integers, representing the length of each sequence
  • Mathematica uses the standard IUB/IUPAC abbreviations for nucleic acids:
Aadenosine
Ccytidine
Gguanine
Tthymidine
Uuracil
Rpurine (G or A)
Ypyrimidine (T or C)
Kketone (G or T)
Mamino group (A or C)
Sstrong interaction (G or C)
Wweak interaction (A or T)
BC or G or T
DA or G or T
HA or C or T
VA or C or G
Nany nucleic acid (A or C or G or T)
-gap of indeterminate length
  • Codes representing amino acids:
Aalanine (Ala)
Beither aspartic acid or asparagine
Ccysteine (Cys)
Daspartic acid (Asp)
Eglutamic acid (Glu)
Fphenylalanine (Phe)
Gglycine (Gly)
Hhistidine (His)
Iisoleucine (Ile)
Klysine (Lys)
Lleucine (Leu)
Mmethionine (Met)
Nasparagine (Asn)
Pproline (Pro)
Qglutamine (Gln)
Rarginine (Arg)
Sserine (Ser)
Tthreonine (Thr)
Uselenocysteine
Vvaline (Val)
Wtryptophan (Trp)
Ytyrosine (Tyr)
Zeither glutamic acid or glutamine
Xany amino acid
*translation stop
-gap of indeterminate length
"HeaderFormat"Automaticspecifies the format of the header
  • Import uses a large built-in library of header format specifications found in common variants of the FASTA format.
  • By setting to a list of literal strings and names of meta-information elements, any header line format can be specified on Import.
  • is a setting typical for NCBI Fasta files.
"LineWidth"70maximum number of characters in a line
This reads the raw header line from a sample FASTA file:
Extract the accession string:
Parse the GenBank database key and the description string from the header line:
Read the first letters of the DNA sequence:
This converts a short sequence to the FASTA format, automatically adding default header information:
This exports two sequences:
This exports a pair of headers and sequences:
Import the previous output using the element gives raw headers and sequences:
Import as a list of rules:
This reads the raw header line from a sample FASTA file:
In[1]:=
Click for copyable input
Out[1]=
 
Extract the accession string:
In[1]:=
Click for copyable input
Out[1]=
 
Parse the GenBank database key and the description string from the header line:
In[1]:=
Click for copyable input
Out[1]=
 
Read the first letters of the DNA sequence:
In[1]:=
Click for copyable input
Out[1]=
 
This converts a short sequence to the FASTA format, automatically adding default header information:
In[1]:=
Click for copyable input
Out[1]=
 
This exports two sequences:
In[1]:=
Click for copyable input
Out[1]=
 
This exports a pair of headers and sequences:
In[1]:=
Click for copyable input
Out[1]=
Import the previous output using the element gives raw headers and sequences:
In[2]:=
Click for copyable input
Out[2]=
Import as a list of rules:
In[3]:=
Click for copyable input
Out[3]=