chips |
This is a simple measure that quantifies how far the codon usage of a gene departs from equal usage of synonymous codons. This measure of synonymous codon usage bias, the 'effective number of codons used in a gene', Nc, can be easily calculated from codon usage data alone, and is independent of gene length and amino acid (aa) composition. Nc can take values from 20, in the case of extreme bias where one codon is exclusively used for each aa, to 61 when the use of alternative synonymous codons is equally likely. Nc thus provides an intuitively meaningful measure of the extent of codon preference in a gene.
The Nc statistic has problems in very short sequences (20 amino acids or less) which are yet to be fully resolved. They are caused by the need to consider amino acids which are missing in the sequence.
This calculation was originally in the EGCG package as "codfish" (codon usage for fission yeast). As Frank Wright is a vegan, we looked for a meat-free name for the EMBOSS version, "chips". The official explanation is "Codon Heterozygosity (Inverse of) in a Protein-coding Sequence"
If the sequence extends beyond the coding region then the start and/or end positions of the CDS must be provided because chips analyses exclusively protein coding regions.
% chips -sbeg 135 -send 1292 Codon usage statistics Input nucleotide sequence(s): tembl:x13776 Output file [x13776.chips]: |
Go to the input files for this example
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Standard (Mandatory) qualifiers: [-seqall] seqall Nucleotide sequence(s) filename and optional format, or reference (input USA) [-outfile] outfile [*.chips] Output file name Additional (Optional) qualifiers: (none) Advanced (Unprompted) qualifiers: -[no]sum boolean [Y] Sum codons over all sequences Associated qualifiers: "-seqall" associated qualifiers -sbegin1 integer Start of each sequence to be used -send1 integer End of each 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 -odirectory2 string Output directory General qualifiers: -auto boolean Turn off prompts -stdout boolean Write standard output -filter boolean Read standard input, write 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 | |
---|---|---|---|
[-seqall] (Parameter 1) |
Nucleotide sequence(s) filename and optional format, or reference (input USA) | Readable sequence(s) | Required |
[-outfile] (Parameter 2) |
Output file name | Output file | <*>.chips |
Additional (Optional) qualifiers | Allowed values | Default | |
(none) | |||
Advanced (Unprompted) qualifiers | Allowed values | Default | |
-[no]sum | Sum codons over all sequences | Boolean value Yes/No | Yes |
ID X13776; SV 1; linear; genomic DNA; STD; PRO; 2167 BP. XX AC X13776; M43175; XX DT 19-APR-1989 (Rel. 19, Created) DT 14-NOV-2006 (Rel. 89, Last updated, Version 24) XX DE Pseudomonas aeruginosa amiC and amiR gene for aliphatic amidase regulation XX KW aliphatic amidase regulator; amiC gene; amiR gene. XX OS Pseudomonas aeruginosa OC Bacteria; Proteobacteria; Gammaproteobacteria; Pseudomonadales; OC Pseudomonadaceae; Pseudomonas. XX RN [1] RP 1167-2167 RA Rice P.M.; RT ; RL Submitted (16-DEC-1988) to the EMBL/GenBank/DDBJ databases. RL Rice P.M., EMBL, Postfach 10-2209, Meyerhofstrasse 1, 6900 Heidelberg, FRG. XX RN [2] RP 1167-2167 RX DOI; 10.1016/0014-5793(89)80249-2. RX PUBMED; 2495988. RA Lowe N., Rice P.M., Drew R.E.; RT "Nucleotide sequence of the aliphatic amidase regulator gene of Pseudomonas RT aeruginosa"; RL FEBS Lett. 246(1-2):39-43(1989). XX RN [3] RP 1-1292 RX PUBMED; 1907262. RA Wilson S., Drew R.; RT "Cloning and DNA seqence of amiC, a new gene regulating expression of the RT Pseudomonas aeruginosa aliphatic amidase, and purification of the amiC RT product."; RL J. Bacteriol. 173(16):4914-4921(1991). XX RN [4] RP 1-2167 RA Rice P.M.; RT ; RL Submitted (04-SEP-1991) to the EMBL/GenBank/DDBJ databases. RL Rice P.M., EMBL, Postfach 10-2209, Meyerhofstrasse 1, 6900 Heidelberg, FRG. XX DR GOA; Q51417. DR UniProtKB/Swiss-Prot; Q51417; AMIS_PSEAE. XX [Part of this file has been deleted for brevity] FT /replace="" FT /note="ClaI fragment deleted in pSW36, constitutive FT phenotype" FT misc_feature 1 FT /note="last base of an XhoI site" FT misc_feature 648..653 FT /note="end of 658bp XhoI fragment, deletion in pSW3 causes FT constitutive expression of amiE" FT conflict 1281 FT /replace="g" FT /citation=[3] XX SQ Sequence 2167 BP; 363 A; 712 C; 730 G; 362 T; 0 other; ggtaccgctg gccgagcatc tgctcgatca ccaccagccg ggcgacggga actgcacgat 60 ctacctggcg agcctggagc acgagcgggt tcgcttcgta cggcgctgag cgacagtcac 120 aggagaggaa acggatggga tcgcaccagg agcggccgct gatcggcctg ctgttctccg 180 aaaccggcgt caccgccgat atcgagcgct cgcacgcgta tggcgcattg ctcgcggtcg 240 agcaactgaa ccgcgagggc ggcgtcggcg gtcgcccgat cgaaacgctg tcccaggacc 300 ccggcggcga cccggaccgc tatcggctgt gcgccgagga cttcattcgc aaccgggggg 360 tacggttcct cgtgggctgc tacatgtcgc acacgcgcaa ggcggtgatg ccggtggtcg 420 agcgcgccga cgcgctgctc tgctacccga ccccctacga gggcttcgag tattcgccga 480 acatcgtcta cggcggtccg gcgccgaacc agaacagtgc gccgctggcg gcgtacctga 540 ttcgccacta cggcgagcgg gtggtgttca tcggctcgga ctacatctat ccgcgggaaa 600 gcaaccatgt gatgcgccac ctgtatcgcc agcacggcgg cacggtgctc gaggaaatct 660 acattccgct gtatccctcc gacgacgact tgcagcgcgc cgtcgagcgc atctaccagg 720 cgcgcgccga cgtggtcttc tccaccgtgg tgggcaccgg caccgccgag ctgtatcgcg 780 ccatcgcccg tcgctacggc gacggcaggc ggccgccgat cgccagcctg accaccagcg 840 aggcggaggt ggcgaagatg gagagtgacg tggcagaggg gcaggtggtg gtcgcgcctt 900 acttctccag catcgatacg cccgccagcc gggccttcgt ccaggcctgc catggtttct 960 tcccggagaa cgcgaccatc accgcctggg ccgaggcggc ctactggcag accttgttgc 1020 tcggccgcgc cgcgcaggcc gcaggcaact ggcgggtgga agacgtgcag cggcacctgt 1080 acgacatcga catcgacgcg ccacaggggc cggtccgggt ggagcgccag aacaaccaca 1140 gccgcctgtc ttcgcgcatc gcggaaatcg atgcgcgcgg cgtgttccag gtccgctggc 1200 agtcgcccga accgattcgc cccgaccctt atgtcgtcgt gcataacctc gacgactggt 1260 ccgccagcat gggcggggga ccgctcccat gagcgccaac tcgctgctcg gcagcctgcg 1320 cgagttgcag gtgctggtcc tcaacccgcc gggggaggtc agcgacgccc tggtcttgca 1380 gctgatccgc atcggttgtt cggtgcgcca gtgctggccg ccgccggaag ccttcgacgt 1440 gccggtggac gtggtcttca ccagcatttt ccagaatggc caccacgacg agatcgctgc 1500 gctgctcgcc gccgggactc cgcgcactac cctggtggcg ctggtggagt acgaaagccc 1560 cgcggtgctc tcgcagatca tcgagctgga gtgccacggc gtgatcaccc agccgctcga 1620 tgcccaccgg gtgctgcctg tgctggtatc ggcgcggcgc atcagcgagg aaatggcgaa 1680 gctgaagcag aagaccgagc agctccagga ccgcatcgcc ggccaggccc ggatcaacca 1740 ggccaaggtg ttgctgatgc agcgccatgg ctgggacgag cgcgaggcgc accagcacct 1800 gtcgcgggaa gcgatgaagc ggcgcgagcc gatcctgaag atcgctcagg agttgctggg 1860 aaacgagccg tccgcctgag cgatccgggc cgaccagaac aataacaaga ggggtatcgt 1920 catcatgctg ggactggttc tgctgtacgt tggcgcggtg ctgtttctca atgccgtctg 1980 gttgctgggc aagatcagcg gtcgggaggt ggcggtgatc aacttcctgg tcggcgtgct 2040 gagcgcctgc gtcgcgttct acctgatctt ttccgcagca gccgggcagg gctcgctgaa 2100 ggccggagcg ctgaccctgc tattcgcttt tacctatctg tgggtggccg ccaaccagtt 2160 cctcgag 2167 // |
# CHIPS codon usage statistics Nc = 32.951 |
The codon usage table is by default the file "CODONS/Ehum.cut" in the EMBOSS distribution directory.
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:
Program name | Description |
---|---|
cai | CAI codon adaptation index |
codcmp | Codon usage table comparison |
cusp | Create a codon usage table |
syco | Synonymous codon usage Gribskov statistic plot |