Amino acid dipepetide frequency for Ciona intestinalis (Transparent sea squirt) (Ascidia intestinalis)

Apart from single amino acid frequencies one can also calculate so called amino acid dipeptide frequency.

There is 400 possibilites (441 if we consider Xaa as additional 21st amino acid representing all non-standard or unknown amino acids). Thus, if the dipeptides would be present randomly in proteins each amino acid dipeptide should be present with 0.25% frequency. As it is not the case in the nature, for better visablity all more than expected dipepetides are marked by red, and those which are underrepresented are marked by blue in the table.

All values are presented as per milles (‰), therefore need to be multiplied by 10^-3.

For more information see sequence space article on Wikipedia.

	Ala	Cys	Asp	Glu	Phe	Gly	His	Ile	Lys	Leu	Met	Asn	Pro	Gln	Arg	Ser	Thr	Val	Trp	Tyr	Xaa
Ala	4.578AlaAla: 4.578 ± 0.04	1.33AlaCys: 1.33 ± 0.021	2.847AlaAsp: 2.847 ± 0.022	3.517AlaGlu: 3.517 ± 0.028	2.354AlaPhe: 2.354 ± 0.024	3.511AlaGly: 3.511 ± 0.035	1.245AlaHis: 1.245 ± 0.016	3.379AlaIle: 3.379 ± 0.031	3.561AlaLys: 3.561 ± 0.029	5.298AlaLeu: 5.298 ± 0.038	1.609AlaMet: 1.609 ± 0.02	2.614AlaAsn: 2.614 ± 0.027	2.523AlaPro: 2.523 ± 0.028	2.163AlaGln: 2.163 ± 0.024	2.73AlaArg: 2.73 ± 0.023	4.794AlaSer: 4.794 ± 0.034	3.883AlaThr: 3.883 ± 0.03	4.354AlaVal: 4.354 ± 0.031	0.685AlaTrp: 0.685 ± 0.014	1.711AlaTyr: 1.711 ± 0.02	0.001AlaXaa: 0.001 ± 0.0
Cys	1.223CysAla: 1.223 ± 0.023	0.704CysCys: 0.704 ± 0.018	1.401CysAsp: 1.401 ± 0.027	1.261CysGlu: 1.261 ± 0.024	0.969CysPhe: 0.969 ± 0.015	1.58CysGly: 1.58 ± 0.024	0.613CysHis: 0.613 ± 0.016	1.275CysIle: 1.275 ± 0.019	1.32CysLys: 1.32 ± 0.021	2.003CysLeu: 2.003 ± 0.024	0.567CysMet: 0.567 ± 0.011	1.226CysAsn: 1.226 ± 0.026	1.122CysPro: 1.122 ± 0.024	0.87CysGln: 0.87 ± 0.014	1.172CysArg: 1.172 ± 0.02	1.98CysSer: 1.98 ± 0.032	1.348CysThr: 1.348 ± 0.032	1.601CysVal: 1.601 ± 0.027	0.284CysTrp: 0.284 ± 0.007	0.742CysTyr: 0.742 ± 0.013	0.0CysXaa: 0.0 ± 0.0
Asp	3.118AspAla: 3.118 ± 0.027	1.141AspCys: 1.141 ± 0.02	3.723AspAsp: 3.723 ± 0.035	4.031AspGlu: 4.031 ± 0.033	2.284AspPhe: 2.284 ± 0.022	3.457AspGly: 3.457 ± 0.042	1.248AspHis: 1.248 ± 0.015	3.286AspIle: 3.286 ± 0.029	3.042AspLys: 3.042 ± 0.027	4.622AspLeu: 4.622 ± 0.031	1.276AspMet: 1.276 ± 0.015	2.437AspAsn: 2.437 ± 0.021	2.338AspPro: 2.338 ± 0.02	1.903AspGln: 1.903 ± 0.022	2.416AspArg: 2.416 ± 0.025	3.777AspSer: 3.777 ± 0.031	2.708AspThr: 2.708 ± 0.026	4.298AspVal: 4.298 ± 0.035	0.658AspTrp: 0.658 ± 0.012	1.703AspTyr: 1.703 ± 0.021	0.001AspXaa: 0.001 ± 0.0
Glu	3.768GluAla: 3.768 ± 0.028	1.31GluCys: 1.31 ± 0.029	3.719GluAsp: 3.719 ± 0.032	5.456GluGlu: 5.456 ± 0.064	2.228GluPhe: 2.228 ± 0.019	2.81GluGly: 2.81 ± 0.03	1.384GluHis: 1.384 ± 0.017	3.675GluIle: 3.675 ± 0.028	4.781GluLys: 4.781 ± 0.045	5.259GluLeu: 5.259 ± 0.044	1.748GluMet: 1.748 ± 0.019	3.648GluAsn: 3.648 ± 0.032	2.155GluPro: 2.155 ± 0.025	2.635GluGln: 2.635 ± 0.032	3.296GluArg: 3.296 ± 0.032	4.201GluSer: 4.201 ± 0.031	3.647GluThr: 3.647 ± 0.026	3.957GluVal: 3.957 ± 0.033	0.694GluTrp: 0.694 ± 0.012	1.808GluTyr: 1.808 ± 0.022	0.001GluXaa: 0.001 ± 0.0
Phe	2.336PheAla: 2.336 ± 0.025	0.986PheCys: 0.986 ± 0.014	2.255PheAsp: 2.255 ± 0.023	2.175PheGlu: 2.175 ± 0.021	1.735PhePhe: 1.735 ± 0.023	2.563PheGly: 2.563 ± 0.025	1.118PheHis: 1.118 ± 0.016	2.449PheIle: 2.449 ± 0.027	2.343PheLys: 2.343 ± 0.021	3.717PheLeu: 3.717 ± 0.042	0.997PheMet: 0.997 ± 0.014	2.157PheAsn: 2.157 ± 0.022	1.844PhePro: 1.844 ± 0.021	1.631PheGln: 1.631 ± 0.019	1.927PheArg: 1.927 ± 0.027	3.264PheSer: 3.264 ± 0.027	2.517PheThr: 2.517 ± 0.028	2.935PheVal: 2.935 ± 0.026	0.487PheTrp: 0.487 ± 0.01	1.473PheTyr: 1.473 ± 0.02	0.0PheXaa: 0.0 ± 0.0
Gly	3.147GlyAla: 3.147 ± 0.026	1.275GlyCys: 1.275 ± 0.023	2.984GlyAsp: 2.984 ± 0.029	3.219GlyGlu: 3.219 ± 0.037	2.584GlyPhe: 2.584 ± 0.026	4.145GlyGly: 4.145 ± 0.046	1.363GlyHis: 1.363 ± 0.017	3.251GlyIle: 3.251 ± 0.027	3.715GlyLys: 3.715 ± 0.032	4.597GlyLeu: 4.597 ± 0.039	1.429GlyMet: 1.429 ± 0.017	3.001GlyAsn: 3.001 ± 0.027	2.066GlyPro: 2.066 ± 0.039	2.017GlyGln: 2.017 ± 0.026	2.989GlyArg: 2.989 ± 0.03	4.817GlySer: 4.817 ± 0.044	3.2GlyThr: 3.2 ± 0.034	3.862GlyVal: 3.862 ± 0.032	0.781GlyTrp: 0.781 ± 0.014	2.104GlyTyr: 2.104 ± 0.027	0.001GlyXaa: 0.001 ± 0.0
His	1.356HisAla: 1.356 ± 0.017	0.658HisCys: 0.658 ± 0.013	1.279HisAsp: 1.279 ± 0.016	1.453HisGlu: 1.453 ± 0.018	1.069HisPhe: 1.069 ± 0.015	1.541HisGly: 1.541 ± 0.018	0.915HisHis: 0.915 ± 0.016	1.384HisIle: 1.384 ± 0.017	1.484HisLys: 1.484 ± 0.018	2.335HisLeu: 2.335 ± 0.023	0.594HisMet: 0.594 ± 0.011	1.266HisAsn: 1.266 ± 0.017	1.346HisPro: 1.346 ± 0.018	1.088HisGln: 1.088 ± 0.014	1.422HisArg: 1.422 ± 0.016	1.952HisSer: 1.952 ± 0.018	1.389HisThr: 1.389 ± 0.018	1.654HisVal: 1.654 ± 0.018	0.313HisTrp: 0.313 ± 0.007	0.853HisTyr: 0.853 ± 0.012	0.0HisXaa: 0.0 ± 0.0
Ile	3.345IleAla: 3.345 ± 0.027	1.323IleCys: 1.323 ± 0.019	2.87IleAsp: 2.87 ± 0.025	3.217IleGlu: 3.217 ± 0.027	2.387IlePhe: 2.387 ± 0.027	3.151IleGly: 3.151 ± 0.027	1.436IleHis: 1.436 ± 0.016	3.197IleIle: 3.197 ± 0.025	3.478IleLys: 3.478 ± 0.026	5.078IleLeu: 5.078 ± 0.039	1.352IleMet: 1.352 ± 0.015	2.867IleAsn: 2.867 ± 0.022	2.823IlePro: 2.823 ± 0.025	2.346IleGln: 2.346 ± 0.021	2.77IleArg: 2.77 ± 0.026	4.586IleSer: 4.586 ± 0.03	3.55IleThr: 3.55 ± 0.036	3.593IleVal: 3.593 ± 0.026	0.6IleTrp: 0.6 ± 0.011	1.797IleTyr: 1.797 ± 0.02	0.001IleXaa: 0.001 ± 0.0
Lys	3.366LysAla: 3.366 ± 0.028	1.361LysCys: 1.361 ± 0.02	3.23LysAsp: 3.23 ± 0.03	4.445LysGlu: 4.445 ± 0.045	2.416LysPhe: 2.416 ± 0.023	2.787LysGly: 2.787 ± 0.033	1.693LysHis: 1.693 ± 0.018	3.598LysIle: 3.598 ± 0.028	5.192LysLys: 5.192 ± 0.059	6.148LysLeu: 6.148 ± 0.042	1.726LysMet: 1.726 ± 0.021	3.095LysAsn: 3.095 ± 0.025	2.998LysPro: 2.998 ± 0.031	3.157LysGln: 3.157 ± 0.026	3.756LysArg: 3.756 ± 0.033	5.011LysSer: 5.011 ± 0.04	3.744LysThr: 3.744 ± 0.031	4.054LysVal: 4.054 ± 0.03	0.77LysTrp: 0.77 ± 0.01	2.159LysTyr: 2.159 ± 0.02	0.001LysXaa: 0.001 ± 0.0
Leu	5.26LeuAla: 5.26 ± 0.039	2.031LeuCys: 2.031 ± 0.022	4.479LeuAsp: 4.479 ± 0.032	5.375LeuGlu: 5.375 ± 0.046	3.68LeuPhe: 3.68 ± 0.036	4.384LeuGly: 4.384 ± 0.034	2.511LeuHis: 2.511 ± 0.023	4.497LeuIle: 4.497 ± 0.032	6.014LeuLys: 6.014 ± 0.039	8.671LeuLeu: 8.671 ± 0.07	2.159LeuMet: 2.159 ± 0.024	4.484LeuAsn: 4.484 ± 0.03	4.54LeuPro: 4.54 ± 0.035	4.313LeuGln: 4.313 ± 0.033	4.712LeuArg: 4.712 ± 0.036	7.169LeuSer: 7.169 ± 0.045	5.166LeuThr: 5.166 ± 0.036	5.6LeuVal: 5.6 ± 0.037	0.992LeuTrp: 0.992 ± 0.013	2.748LeuTyr: 2.748 ± 0.023	0.002LeuXaa: 0.002 ± 0.001
Met	1.654MetAla: 1.654 ± 0.018	0.508MetCys: 0.508 ± 0.011	1.358MetAsp: 1.358 ± 0.015	1.769MetGlu: 1.769 ± 0.022	1.142MetPhe: 1.142 ± 0.015	1.282MetGly: 1.282 ± 0.017	0.589MetHis: 0.589 ± 0.009	1.213MetIle: 1.213 ± 0.016	1.879MetLys: 1.879 ± 0.02	2.362MetLeu: 2.362 ± 0.022	0.785MetMet: 0.785 ± 0.012	1.306MetAsn: 1.306 ± 0.016	1.027MetPro: 1.027 ± 0.015	1.16MetGln: 1.16 ± 0.016	1.274MetArg: 1.274 ± 0.014	1.973MetSer: 1.973 ± 0.019	1.519MetThr: 1.519 ± 0.017	1.588MetVal: 1.588 ± 0.016	0.294MetTrp: 0.294 ± 0.007	0.751MetTyr: 0.751 ± 0.012	0.001MetXaa: 0.001 ± 0.0
Asn	2.774AsnAla: 2.774 ± 0.023	1.18AsnCys: 1.18 ± 0.023	2.697AsnAsp: 2.697 ± 0.024	3.425AsnGlu: 3.425 ± 0.029	2.092AsnPhe: 2.092 ± 0.021	3.198AsnGly: 3.198 ± 0.034	1.242AsnHis: 1.242 ± 0.015	3.258AsnIle: 3.258 ± 0.026	3.37AsnLys: 3.37 ± 0.028	4.517AsnLeu: 4.517 ± 0.03	1.306AsnMet: 1.306 ± 0.015	2.991AsnAsn: 2.991 ± 0.033	2.52AsnPro: 2.52 ± 0.024	2.277AsnGln: 2.277 ± 0.022	2.371AsnArg: 2.371 ± 0.024	3.848AsnSer: 3.848 ± 0.029	3.004AsnThr: 3.004 ± 0.027	3.314AsnVal: 3.314 ± 0.025	0.571AsnTrp: 0.571 ± 0.013	1.603AsnTyr: 1.603 ± 0.02	0.001AsnXaa: 0.001 ± 0.0
Pro	2.723ProAla: 2.723 ± 0.027	0.938ProCys: 0.938 ± 0.023	2.568ProAsp: 2.568 ± 0.026	2.749ProGlu: 2.749 ± 0.027	1.62ProPhe: 1.62 ± 0.02	2.882ProGly: 2.882 ± 0.057	1.244ProHis: 1.244 ± 0.016	2.394ProIle: 2.394 ± 0.024	2.646ProLys: 2.646 ± 0.025	3.628ProLeu: 3.628 ± 0.025	1.073ProMet: 1.073 ± 0.018	2.412ProAsn: 2.412 ± 0.026	3.555ProPro: 3.555 ± 0.058	1.953ProGln: 1.953 ± 0.023	2.221ProArg: 2.221 ± 0.024	4.115ProSer: 4.115 ± 0.033	3.415ProThr: 3.415 ± 0.038	3.098ProVal: 3.098 ± 0.029	0.497ProTrp: 0.497 ± 0.009	1.428ProTyr: 1.428 ± 0.017	0.001ProXaa: 0.001 ± 0.0
Gln	2.439GlnAla: 2.439 ± 0.024	0.986GlnCys: 0.986 ± 0.02	1.909GlnAsp: 1.909 ± 0.019	2.569GlnGlu: 2.569 ± 0.026	1.536GlnPhe: 1.536 ± 0.017	1.874GlnGly: 1.874 ± 0.022	1.261GlnHis: 1.261 ± 0.015	2.24GlnIle: 2.24 ± 0.021	2.546GlnLys: 2.546 ± 0.026	4.038GlnLeu: 4.038 ± 0.031	1.091GlnMet: 1.091 ± 0.016	2.171GlnAsn: 2.171 ± 0.024	2.078GlnPro: 2.078 ± 0.03	2.674GlnGln: 2.674 ± 0.037	2.39GlnArg: 2.39 ± 0.025	3.142GlnSer: 3.142 ± 0.027	2.471GlnThr: 2.471 ± 0.023	2.63GlnVal: 2.63 ± 0.023	0.505GlnTrp: 0.505 ± 0.01	1.27GlnTyr: 1.27 ± 0.016	0.001GlnXaa: 0.001 ± 0.0
Arg	2.658ArgAla: 2.658 ± 0.022	1.199ArgCys: 1.199 ± 0.026	2.588ArgAsp: 2.588 ± 0.025	3.027ArgGlu: 3.027 ± 0.027	2.08ArgPhe: 2.08 ± 0.022	2.705ArgGly: 2.705 ± 0.031	1.492ArgHis: 1.492 ± 0.019	2.813ArgIle: 2.813 ± 0.026	3.919ArgLys: 3.919 ± 0.036	4.437ArgLeu: 4.437 ± 0.034	1.365ArgMet: 1.365 ± 0.016	2.787ArgAsn: 2.787 ± 0.027	2.192ArgPro: 2.192 ± 0.027	2.098ArgGln: 2.098 ± 0.021	3.804ArgArg: 3.804 ± 0.043	4.218ArgSer: 4.218 ± 0.038	2.747ArgThr: 2.747 ± 0.026	2.916ArgVal: 2.916 ± 0.03	0.657ArgTrp: 0.657 ± 0.013	1.676ArgTyr: 1.676 ± 0.02	0.001ArgXaa: 0.001 ± 0.0
Ser	4.658SerAla: 4.658 ± 0.036	1.95SerCys: 1.95 ± 0.03	4.516SerAsp: 4.516 ± 0.036	4.472SerGlu: 4.472 ± 0.036	3.367SerPhe: 3.367 ± 0.027	4.826SerGly: 4.826 ± 0.04	1.971SerHis: 1.971 ± 0.019	4.248SerIle: 4.248 ± 0.028	4.728SerLys: 4.728 ± 0.035	7.002SerLeu: 7.002 ± 0.041	1.991SerMet: 1.991 ± 0.02	4.397SerAsn: 4.397 ± 0.026	4.077SerPro: 4.077 ± 0.043	3.037SerGln: 3.037 ± 0.024	4.0SerArg: 4.0 ± 0.036	8.427SerSer: 8.427 ± 0.071	5.095SerThr: 5.095 ± 0.038	5.303SerVal: 5.303 ± 0.034	0.936SerTrp: 0.936 ± 0.014	2.548SerTyr: 2.548 ± 0.022	0.0SerXaa: 0.0 ± 0.0
Thr	3.671ThrAla: 3.671 ± 0.027	1.688ThrCys: 1.688 ± 0.041	3.064ThrAsp: 3.064 ± 0.028	3.535ThrGlu: 3.535 ± 0.034	2.387ThrPhe: 2.387 ± 0.021	3.586ThrGly: 3.586 ± 0.04	1.369ThrHis: 1.369 ± 0.019	3.271ThrIle: 3.271 ± 0.027	3.659ThrLys: 3.659 ± 0.026	5.122ThrLeu: 5.122 ± 0.036	1.496ThrMet: 1.496 ± 0.017	3.187ThrAsn: 3.187 ± 0.025	3.266ThrPro: 3.266 ± 0.031	2.244ThrGln: 2.244 ± 0.019	2.761ThrArg: 2.761 ± 0.026	5.797ThrSer: 5.797 ± 0.043	4.563ThrThr: 4.563 ± 0.051	3.972ThrVal: 3.972 ± 0.041	0.792ThrTrp: 0.792 ± 0.016	1.774ThrTyr: 1.774 ± 0.021	0.001ThrXaa: 0.001 ± 0.0
Val	4.38ValAla: 4.38 ± 0.03	1.647ValCys: 1.647 ± 0.028	3.555ValAsp: 3.555 ± 0.027	4.057ValGlu: 4.057 ± 0.037	2.829ValPhe: 2.829 ± 0.026	3.764ValGly: 3.764 ± 0.035	1.523ValHis: 1.523 ± 0.017	3.827ValIle: 3.827 ± 0.029	4.098ValLys: 4.098 ± 0.035	5.947ValLeu: 5.947 ± 0.04	1.688ValMet: 1.688 ± 0.019	3.101ValAsn: 3.101 ± 0.028	2.869ValPro: 2.869 ± 0.025	2.55ValGln: 2.55 ± 0.023	3.032ValArg: 3.032 ± 0.022	5.003ValSer: 5.003 ± 0.035	4.692ValThr: 4.692 ± 0.044	4.951ValVal: 4.951 ± 0.034	0.803ValTrp: 0.803 ± 0.013	2.107ValTyr: 2.107 ± 0.022	0.001ValXaa: 0.001 ± 0.0
Trp	0.565TrpAla: 0.565 ± 0.011	0.27TrpCys: 0.27 ± 0.007	0.623TrpAsp: 0.623 ± 0.011	0.656TrpGlu: 0.656 ± 0.012	0.553TrpPhe: 0.553 ± 0.011	0.658TrpGly: 0.658 ± 0.013	0.278TrpHis: 0.278 ± 0.007	0.659TrpIle: 0.659 ± 0.013	0.913TrpLys: 0.913 ± 0.014	1.117TrpLeu: 1.117 ± 0.016	0.352TrpMet: 0.352 ± 0.009	0.684TrpAsn: 0.684 ± 0.012	0.409TrpPro: 0.409 ± 0.009	0.443TrpGln: 0.443 ± 0.009	0.682TrpArg: 0.682 ± 0.012	1.059TrpSer: 1.059 ± 0.021	0.676TrpThr: 0.676 ± 0.014	0.697TrpVal: 0.697 ± 0.013	0.209TrpTrp: 0.209 ± 0.006	0.409TrpTyr: 0.409 ± 0.009	0.0TrpXaa: 0.0 ± 0.0
Tyr	1.667TyrAla: 1.667 ± 0.019	0.774TyrCys: 0.774 ± 0.015	1.803TyrAsp: 1.803 ± 0.018	1.772TyrGlu: 1.772 ± 0.022	1.599TyrPhe: 1.599 ± 0.022	1.845TyrGly: 1.845 ± 0.018	0.859TyrHis: 0.859 ± 0.013	1.851TyrIle: 1.851 ± 0.02	2.016TyrLys: 2.016 ± 0.019	2.886TyrLeu: 2.886 ± 0.029	0.83TyrMet: 0.83 ± 0.013	1.727TyrAsn: 1.727 ± 0.019	1.409TyrPro: 1.409 ± 0.019	1.261TyrGln: 1.261 ± 0.018	1.65TyrArg: 1.65 ± 0.018	2.415TyrSer: 2.415 ± 0.024	1.871TyrThr: 1.871 ± 0.02	2.045TyrVal: 2.045 ± 0.021	0.385TyrTrp: 0.385 ± 0.009	1.208TyrTyr: 1.208 ± 0.016	0.0TyrXaa: 0.0 ± 0.0
Xaa	0.001XaaAla: 0.001 ± 0.0	0.0XaaCys: 0.0 ± 0.0	0.001XaaAsp: 0.001 ± 0.0	0.001XaaGlu: 0.001 ± 0.0	0.001XaaPhe: 0.001 ± 0.0	0.001XaaGly: 0.001 ± 0.0	0.0XaaHis: 0.0 ± 0.0	0.0XaaIle: 0.0 ± 0.0	0.002XaaLys: 0.002 ± 0.001	0.002XaaLeu: 0.002 ± 0.001	0.0XaaMet: 0.0 ± 0.0	0.0XaaAsn: 0.0 ± 0.0	0.001XaaPro: 0.001 ± 0.0	0.001XaaGln: 0.001 ± 0.0	0.001XaaArg: 0.001 ± 0.0	0.001XaaSer: 0.001 ± 0.0	0.0XaaThr: 0.0 ± 0.0	0.001XaaVal: 0.001 ± 0.0	0.0XaaTrp: 0.0 ± 0.0	0.001XaaTyr: 0.001 ± 0.0	0.007XaaXaa: 0.007 ± 0.002

Statistics based on 17309 proteins (5768025 amino acids)

Note: The error has been estimated with the bootstraping (x100) at the protein level

Above dipeptide statistics (among other stats for this proteome) you can download from this CSV file

Reference: Kozlowski LP. Proteome-pI 2.0: Proteome Isoelectric Point Database Update. Nucleic Acids Res. 2021, doi: 10.1093/nar/gkab944

Contact: Lukasz P. Kozlowski

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