Lysines and cysteines of the Homo sapiens IGHG1, IGKC and IGLC1 and positions in the C-DOMAIN

C-DOMAIN strands, turns and loops IMGT position Homo sapiens IGHG1 Homo sapiens IGKC Homo sapiens IGLC1
A-STRAND 1.5-15 K1.1
K12 K12
B-STRAND 16-26 K16
C23 C23 C23 C23 C23
BC-LOOP 27-38 K38 K38
C-STRAND 39-45 W41 W41 W41 W41 W41
K42 K42
CD-STRAND 45.1-45.5 K45.4
D-STRAND 77-84 K79 K79
DE-TURN 84.1-85.1 K84.1
N84.4 K84.4
E-STRAND 85-93 K88
V89 L89 L89 L89 L89
K93 K93
F-STRAND 97-104 K97
K100 K100
C104 C104 C104 C104 C104
FG-LOOP 105-117 K105
K109 K109
G-STRAND 118-127 D118 E118 Q118 T118 E118
K119 K119 K119 K119 K119
CHS K130
Nb of lysines 6 12 7 8 9

Positions are according to the IMGT unique numbering for C-DOMAIN [1]. For correspondence between the IMGT unique numbering with other numberings, see Correspondence between C numberings.

Sequences are from Homo sapiens IGHG1*01 (J00228), Homo sapiens IGKC*01 (J00241) and Homo sapiens IGLC1*02 (X51755).

In addition to the lysines are shown:
- the five characteristic amino acids of a C-DOMAIN [2,3]. Four of them are highly conserved and hydrophobic [4] and are common to the V domain: C23 (1st-CYS), W41 (CONSERVED-TRP), 89 (hydrophobic) and C104 (2nd-CYS) [5]. These four amino acids contribute to the two major features shared by the V and C domains: the disulfide bridge (between the two cysteines 23 and 104) and the internal hydrophobic core of the domain (with the side chains of tryptophan W41 and amino acid 89) [2,3]. The fifth position, 118 is diverse in the C-DOMAIN and is characterized as being an FG loop anchor (whereas it is conserved in the V-DOMAIN and represented by J-PHE 118 or J-TRP 118).
- the CH2 N84.4 site of N-glycosylation (IMGT Lexique Glycosylation) at the top of the DE turn. The asparagine N84.4 is part of a N-glycosylation motif NXS/T (NST in Homo sapiens IGHG1).

[1] Lefranc et al DCI 2005.
[2] Lefranc, M-P. Immunoglobulin (IG) and T cell receptor genes (TR): IMGT® and the birth and rise of immunoinformatics. Front Immunol. 2014 Feb 05;5:22. doi: 10.3389/fimmu.2014.00022. Open access. PMID: 24600447.
[3] Lefranc, M-P. Immunoglobulins: 25 years of Immunoinformatics and IMGT-ONTOLOGY. Biomolecules. 2014, 4(4), 1102-1139; doi:10.3390/biom4041102. Open access. PMID: 25521638.
[4] Pommié, C., Levadoux, S., Sabatier, R., Lefranc, G. and Lefranc, M.-P. IMGT standardized criteria for statistical analysis of immunoglobulin V-REGION amino acid properties J. Mol. Recognit., 17, 17-32 (2004). PMID: 14872534 pdf

[5] Lefranc, M.-P., Pommié, C., Ruiz, M., Giudicelli, V., Foulquier, E., Truong, L., Thouvenin-Contet, V. and Lefranc, G. IMGT unique numbering for immunoglobulin and T cell receptor variable domains and Ig superfamily V-like domains. Dev. Comp. Immunol., 27, 55-77 (2003). PMID: 12477501 pdf with permission from Elsevier.

Software material and data coming from IMGT server may be used for academic research only, provided that it is referred to IMGT®, and cited as "IMGT®, the international ImMunoGeneTics information system® (founder and director: Marie-Paule Lefranc, Montpellier, France)." References to cite: Lefranc, M.-P. et al., Nucleic Acids Res., 27:209-212 (1999); doi: 10.1093/nar/27.1.209 Full text Cover; Ruiz, M. et al., Nucleic Acids Res., 28:219-221 (2000); doi: 10.1093/nar/28.1.219 Full text; Lefranc, M.-P., Nucleic Acids Res., 29:207-209 (2001); doi: 10.1093/nar/29.1.207 Full text; Lefranc, M.-P., Nucleic Acids Res., 31:307-310 (2003); doi: 10.1093/nar/gkg085 Full text; Lefranc, M.-P. et al., In Silico Biol., 5, 0006 (2004) [Epub], 5:45-60 (2005); Lefranc, M.-P. et al., Nucleic Acids Res., 33:D593-597 (2005); doi: 10.1093/nar/gki065 Full text; Lefranc, M.-P. et al., Nucleic Acids Res., 37:D1006-1012 (2009); doi: 10.1093/nar/gkn838 Full text; Lefranc, M.-P. et al., Nucleic Acids Res., 43:D413-422 (2015); doi: 10.1093/nar/gku1056 Full text.
For any other use please contact Marie-Paule Lefranc

CNRS Université de Montpellier European Commission
IMGT® Founder and Executive Director Emeritus:
Marie-Paule Lefranc
IMGT® Director:
Sofia Kossida
Bioinformatics manager:
Véronique Giudicelli
Computer manager:
Patrice Duroux
Amélie Houles

Citing IMGT | Warranty disclaimer and copyright notice | Privacy policy and advertisement policy

© Copyright 1995-2017 IMGT®, the international ImMunoGeneTics information system®