MPEP 2412.03(b)
"Amino Acid"

Ninth Edition of the MPEP, Revision 07.2022, Last Revised in February 2023

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2412.03(b)    "Amino Acid" [R-07.2022]

[Editor Note: This section is applicable to all applications filed on or after July 1, 2022, having disclosures of nucleotide and/or amino acid sequences as defined in 37 CFR 1.831(b). Formatting representations of XML (eXtensible Markup Language) elements in this section appear different than shown in Standard ST.26, which may be accessed at: /export/sites/www/ standards/en/pdf/03-26-01.pdf.]

37 C.F.R. 1.831  Requirements for patent applications filed on or after July 1, 2022, having nucleotide and/or amino acid sequence disclosures.

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  • (f) "Amino acid" includes any D- or L-amino acid or modified amino acid as defined in paragraph 3(a) of WIPO Standard ST.26.
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WIPO Standard ST.26, paragraph 3(a), defines "amino acid" to mean any amino acid that can be represented using any of the symbols shown in Table 3: List of Amino Acid Symbols (reproduced in MPEP § 2412.03(a)). Such amino acids include, inter alia, D-amino acids and amino acids containing modified or synthetic side chains. Amino acids will be construed as unmodified L-amino acids unless further described in a feature table. A peptide nucleic acid (PNA) residue is not considered an amino acid, but is considered a nucleotide.

A modified amino acid must be further described in a feature table. Where applicable, the feature keys "CARBOHYD" or "LIPID" should be used together with the qualifier "note". The feature key "MOD_RES" should be used for other post-translationally modified amino acids together with the qualifier "note"; otherwise the feature key "SITE" together with the qualifier "note" should be used. The value for the qualifier "note" must either be an abbreviation set forth in Table 4 below or the complete, unabbreviated name of the modified amino acid. The abbreviations set forth in Table 4 or the complete, unabbreviated names must not be used in the sequence itself.

Abbreviation Modified Amino acid
Aad  2-Aminoadipic acid 
bAad  3-Aminoadipic acid 
bAla  beta-Alanine, beta-Aminopropionic acid
Abu  2-Aminobutyric acid 
4Abu  4-Aminobutyric acid, piperidinic acid
Acp  6-Aminocaproic acid 
Ahe  2-Aminoheptanoic acid 
Aib  2-Aminoisobutyric acid 
bAib  3-Aminoisobutyric acid 
Apm  2-Aminopimelic acid 
Dbu  2,4 Diaminobutyric acid 
Des  Desmosine 
Dpm  2,2'-Diaminopimelic acid 
Dpr  2,3-Diaminopropionic acid 
EtGly  N-Ethylglycine 
EtAsn  N-Ethylasparagine 
Hyl  Hydroxylysine 
aHyl  allo-Hydroxylysine 
3Hyp  3-Hydroxyproline 
4Hyp  4-Hydroxyproline 
Ide  Isodesmosine 
alle  allo-Isoleucine 
MeGly  N-Methylglycine, sarcosine 
Melle  N-Methylisoleucine 
MeLys  6-N-Methyllysine 
MeVal  N-Methylvaline 
Nva  Norvaline 
Nle  Norleucine 
Orn  Ornithine 

Reproduced from WIPO Standard ST.26, Annex I, Section 4