Contribution of domain interface residues to the stability of antibody CH3 domain homodimers.


Abstract

Dimers of CH3 domains from human IgG1 were used to study the effect of mutations constructed at a domain-domain interface upon domain dissociation and unfolding, "complex stability". Alanine replacement mutants were constructed on one side of the interface for each of the sixteen interdomain contact residues by using a single-chain CH3 dimer in which the carboxyl terminus of one domain was joined to the amino terminus of the second domain via a (G4S)4 linker. Single-chain variants were expressed in Escherichia coli grown in a fermentor and recovered in yields of 6-90 mg L-1 by immobilized metal affinity chromatography. Guanidine hydrochloride-induced denaturation was used to follow domain dissociation and unfolding. Surprisingly, the linker did not perturb the complex stability for either the wild type or two destabilizing mutants. The CH3 domain dissociation and unfolding energetics are dominated by six contact residues where corresponding alanine mutations each destabilize the complex by >2.0 kcal mol-1. Five of these residues (T366, L368, F405, Y407, and K409) form a patch at the center of the interface and are located on the two internal antiparallel beta-strands. These energetically key residues are surrounded by 10 residues on the two external beta-strands whose contribution to complex stability is small (three have a Delta DeltaG of 1.1-1.3 kcal mol-1) or very small (seven have a Delta DeltaG of </=0.7 kcal mol-1). Thus, at the center of the CH3 structural interface there is a small "functional interface" of residues that make significant contributions to complex stability. Study holds ProTherm entries: 3628, 3629, 3630, 3631, 3632, 3633, 3634, 3635, 3636, 3637, 3638, 3639, 3640, 3641, 3642, 3643, 3644 Extra Details: dG and ddG were measured in the presence of [GdnHCl]50% CH3 domain homodimer; alanine mutants; complex stability;,beta-strands; functional interface; IgG

Submission Details

ID: EbJJWbUV3

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:22 p.m.

Version: 1

Publication Details
Dall'Acqua W;Simon AL;Mulkerrin MG;Carter P,Biochemistry (1998) Contribution of domain interface residues to the stability of antibody CH3 domain homodimers. PMID:9649307
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P
 

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)


Relevant PDB Entries

Structure ID Release Date Resolution Structure Title
4HAF 2012-09-26T00:00:00+0000 2.04 Crystal structure of fc-fragment of human IgG2 antibody (primitive crystal form)
4HAG 2012-09-26T00:00:00+0000 3.4 Crystal structure of fc-fragment of human IgG2 antibody (centered crystal form)
4L4J 2013-06-07T00:00:00+0000 1.92 Crystal structure of fc-fragment of human IgG2-Sigma antibody
7LUS 2021-02-23T00:00:00+0000 2.45 IgG2 Fc Charge Pair Mutation version 1 (CPMv1)
7LUS 2021-02-23T00:00:00+0000 2.45 IgG2 Fc Charge Pair Mutation version 1 (CPMv1)
4WWI 2014-11-11T00:00:00+0000 2.31 Crystal structure of the C domain of staphylococcal protein A in complex with the Fc fragment of human IgG at 2.3 Angstrom resolution
4ZNC 2015-05-04T00:00:00+0000 2.28 Fc fragment of human IgG in complex with the C domain of staphylococcal protein A mutant - Q9W
5W38 2017-06-07T00:00:00+0000 1.8 1.80A resolution structure of human IgG3 Fc (N392K)
6D58 2018-04-19T00:00:00+0000 2.39 Crystal structure of a Fc fragment of Human IgG3
1ADQ 1997-02-18T00:00:00+0000 3.15 CRYSTAL STRUCTURE OF A HUMAN IGM RHEUMATOID FACTOR FAB IN COMPLEX WITH ITS AUTOANTIGEN IGG FC

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
92.3 Immunoglobulin heavy constant gamma 1 P01861 IGHG4_HUMAN
92.3 Immunoglobulin heavy constant gamma 1 P01859 IGHG2_HUMAN
100.0 Immunoglobulin heavy constant gamma 1 P01857 IGHG1_HUMAN
100.0 Immunoglobulin heavy constant gamma 1 P0DOX5 IGG1_HUMAN
92.8 Immunoglobulin heavy constant gamma 1 P01860 IGHG3_HUMAN