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Find restriction sites to insert (mutate) with no translation change


silent finds restriction enzyme sites in a nucleotide sequence which can be inserted (mutated) without changing the translation. silent scans a nucleotide sequence for restriction sites for a supplied set of restriction enzymes. It writes a standard EMBOSS report of single base positions which, when mutated, insert the restriction site whilst maintaining the same translation in frame 1 of the input sequence. One or more restriction enzymes can be specified or alternatively all the enzymes in the REBASE database can be investigated. Optionally, all possible mutations are shown and the untranslated and translated sequence are reported.


Here is a sample session with silent

% silent 
Find restriction sites to insert (mutate) with no translation change
Input nucleotide sequence: tembl:x65923
Comma separated enzyme list [all]: ecori,hindiii
Output report [x65923.silent]: 

Go to the input files for this example
Go to the output files for this example

Command line arguments

   Standard (Mandatory) qualifiers:
  [-sequence]          sequence   Nucleotide sequence filename and optional
                                  format, or reference (input USA)
   -enzymes            string     [all] Comma separated enzyme list (Any
                                  string is accepted)
  [-outfile]           report     [*.silent] Output report file name

   Additional (Optional) qualifiers: (none)
   Advanced (Unprompted) qualifiers:
   -sshow              boolean    [N] Display untranslated sequence
   -tshow              boolean    [N] Display translated sequence
   -allmut             boolean    [N] Display all mutations

   Associated qualifiers:

   "-sequence" associated qualifiers
   -sbegin1            integer    Start of the sequence to be used
   -send1              integer    End of the sequence to be used
   -sreverse1          boolean    Reverse (if DNA)
   -sask1              boolean    Ask for begin/end/reverse
   -snucleotide1       boolean    Sequence is nucleotide
   -sprotein1          boolean    Sequence is protein
   -slower1            boolean    Make lower case
   -supper1            boolean    Make upper case
   -sformat1           string     Input sequence format
   -sdbname1           string     Database name
   -sid1               string     Entryname
   -ufo1               string     UFO features
   -fformat1           string     Features format
   -fopenfile1         string     Features file name

   "-outfile" associated qualifiers
   -rformat2           string     Report format
   -rname2             string     Base file name
   -rextension2        string     File name extension
   -rdirectory2        string     Output directory
   -raccshow2          boolean    Show accession number in the report
   -rdesshow2          boolean    Show description in the report
   -rscoreshow2        boolean    Show the score in the report
   -rstrandshow2       boolean    Show the nucleotide strand in the report
   -rusashow2          boolean    Show the full USA in the report
   -rmaxall2           integer    Maximum total hits to report
   -rmaxseq2           integer    Maximum hits to report for one sequence

   General qualifiers:
   -auto               boolean    Turn off prompts
   -stdout             boolean    Write first file to standard output
   -filter             boolean    Read first file from standard input, write
                                  first file to standard output
   -options            boolean    Prompt for standard and additional values
   -debug              boolean    Write debug output to program.dbg
   -verbose            boolean    Report some/full command line options
   -help               boolean    Report command line options. More
                                  information on associated and general
                                  qualifiers can be found with -help -verbose
   -warning            boolean    Report warnings
   -error              boolean    Report errors
   -fatal              boolean    Report fatal errors
   -die                boolean    Report dying program messages

Standard (Mandatory) qualifiers Allowed values Default
(Parameter 1)
Nucleotide sequence filename and optional format, or reference (input USA) Readable sequence Required
-enzymes Comma separated enzyme list Any string is accepted all
(Parameter 2)
Output report file name Report output file <*>.silent
Additional (Optional) qualifiers Allowed values Default
Advanced (Unprompted) qualifiers Allowed values Default
-sshow Display untranslated sequence Boolean value Yes/No No
-tshow Display translated sequence Boolean value Yes/No No
-allmut Display all mutations Boolean value Yes/No No

Input file format

silent reads a nucleic acid sequence USA.

Input files for usage example

'tembl:x65923' is a sequence entry in the example nucleic acid database 'tembl'

Database entry: tembl:x65923

ID   X65923; SV 1; linear; mRNA; STD; HUM; 518 BP.
AC   X65923;
DT   13-MAY-1992 (Rel. 31, Created)
DT   18-APR-2005 (Rel. 83, Last updated, Version 11)
DE   H.sapiens fau mRNA
KW   fau gene.
OS   Homo sapiens (human)
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae;
OC   Homo.
RN   [1]
RP   1-518
RA   Michiels L.M.R.;
RT   ;
RL   Submitted (29-APR-1992) to the EMBL/GenBank/DDBJ databases.
RL   L.M.R. Michiels, University of Antwerp, Dept of Biochemistry,
RL   Universiteisplein 1, 2610 Wilrijk, BELGIUM
RN   [2]
RP   1-518
RX   PUBMED; 8395683.
RA   Michiels L., Van der Rauwelaert E., Van Hasselt F., Kas K., Merregaert J.;
RT   "fau cDNA encodes a ubiquitin-like-S30 fusion protein and is expressed as
RT   an antisense sequence in the Finkel-Biskis-Reilly murine sarcoma virus";
RL   Oncogene 8(9):2537-2546(1993).
DR   H-InvDB; HIT000322806.
FH   Key             Location/Qualifiers
FT   source          1..518
FT                   /organism="Homo sapiens"
FT                   /chromosome="11q"
FT                   /map="13"
FT                   /mol_type="mRNA"
FT                   /clone_lib="cDNA"
FT                   /clone="pUIA 631"
FT                   /tissue_type="placenta"
FT                   /db_xref="taxon:9606"
FT   misc_feature    57..278
FT                   /note="ubiquitin like part"
FT   CDS             57..458
FT                   /gene="fau"
FT                   /db_xref="GDB:135476"
FT                   /db_xref="GOA:P62861"
FT                   /db_xref="HGNC:3597"
FT                   /db_xref="HSSP:1GJZ"
FT                   /db_xref="InterPro:IPR006846"
FT                   /db_xref="UniProtKB/Swiss-Prot:P35544"
FT                   /protein_id="CAA46716.1"
FT   misc_feature    98..102
FT                   /note="nucleolar localization signal"
FT   misc_feature    279..458
FT                   /note="S30 part"
FT   polyA_signal    484..489
FT   polyA_site      509
SQ   Sequence 518 BP; 125 A; 139 C; 148 G; 106 T; 0 other;
     ttcctctttc tcgactccat cttcgcggta gctgggaccg ccgttcagtc gccaatatgc        60
     agctctttgt ccgcgcccag gagctacaca ccttcgaggt gaccggccag gaaacggtcg       120
     cccagatcaa ggctcatgta gcctcactgg agggcattgc cccggaagat caagtcgtgc       180
     tcctggcagg cgcgcccctg gaggatgagg ccactctggg ccagtgcggg gtggaggccc       240
     tgactaccct ggaagtagca ggccgcatgc ttggaggtaa agttcatggt tccctggccc       300
     gtgctggaaa agtgagaggt cagactccta aggtggccaa acaggagaag aagaagaaga       360
     agacaggtcg ggctaagcgg cggatgcagt acaaccggcg ctttgtcaac gttgtgccca       420
     cctttggcaa gaagaagggc cccaatgcca actcttaagt cttttgtaat tctggctttc       480
     tctaataaaa aagccactta gttcagtcaa aaaaaaaa                               518

Output file format

Output files for usage example

File: x65923.silent

# Program: silent
# Rundate: Tue 15 Jul 2008 12:00:00
# Commandline: silent
#    -sequence tembl:x65923
#    -enzymes ecori,hindiii
# Report_format: table
# Report_file: x65923.silent

# Sequence: X65923     from: 1   to: 518
# HitCount: 1
# KEY:
# EnzymeName: Enzyme name
# RS-Pattern: Restriction enzyme recognition site pattern
# Base-Posn: Position of base to be mutated
# AAs: Amino acid. Original sequence(.)After mutation
# Silent: Yes for unchanged amino acid
# Mutation: The base mutation to perform
# Creating silent and non-silent mutations

  Start     End  Strand EnzymeName RS-Pattern Base-Posn    AAs Silent Mutation
    267     272       - HindIII    AAGCTT           268    A.A    Yes     A->T


# Total_sequences: 1
# Total_length: 518
# Reported_sequences: 1
# Reported_hitcount: 1

Data files

EMBOSS data files are distributed with the application and stored in the standard EMBOSS data directory, which is defined by the EMBOSS environment variable EMBOSS_DATA.

To see the available EMBOSS data files, run:

% embossdata -showall

To fetch one of the data files (for example 'Exxx.dat') into your current directory for you to inspect or modify, run:

% embossdata -fetch -file Exxx.dat

Users can provide their own data files in their own directories. Project specific files can be put in the current directory, or for tidier directory listings in a subdirectory called ".embossdata". Files for all EMBOSS runs can be put in the user's home directory, or again in a subdirectory called ".embossdata".

The directories are searched in the following order:

The EMBOSS REBASE restriction enzyme data files are stored in directory 'data/REBASE/*' under the EMBOSS installation directory.

These files must first be set up using the program 'rebaseextract'. Running 'rebaseextract' may be the job of your system manager.

The data files are stored in the REBASE directory of the standard EMBOSS data directory. The names are:

The column information is described at the top of the data files

The reported enzyme from any one group of isoschizomers (the prototype) is specified in the REBASE database and the information is held in the data file 'embossre.equ'. You may edit this file to set your own preferred prototype, if you wish.

The format of the file "embossre.equ" is
Enzyme-name Prototype-name

i.e. two columns of enzyme names separated by a space. The first name of the pair of enzymes is the name that is not preferred and the second is the preferred (prototype) name.






recoder uses the EMBOSS REBASE restriction enzyme data files stored in directory data/REBASE/* under the EMBOSS installation directory. These files must first be set up using the program rebaseextract. Running rebaseextract may be the job of your system manager.

Diagnostic Error Messages


Exit status

It always exits with status 0.

Known bugs


See also

Program name Description
recoder Find restriction sites to remove (mutate) with no translation change
redata Retrieve information from REBASE restriction enzyme database
remap Display restriction enzyme binding sites in a nucleotide sequence
restover Find restriction enzymes producing a specific overhang
restrict Report restriction enzyme cleavage sites in a nucleotide sequence
showseq Displays sequences with features in pretty format

silent does the opposite to recode. silent finds sites where a restriction enzyme site can be introduced without changing the translation in frame 1 of the sequence. recode finds sites where a restriction enzyme site can be removed without changing the translation in frame 1 of the sequence.


Alan Bleasby (ajb ©
European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, UK


Written (Aug 2000) - Alan Bleasby.

Target users

This program is intended to be used by everyone and everything, from naive users to embedded scripts.