Energetic and structural analysis of the role of tryptophan 59 in FKBP12.


Abstract

Tryptophan 59 forms the seat of the hydrophobic ligand-binding site in the small immunophilin FKBP12. Mutating this residue to phenylalanine or leucine stabilizes the protein by 2.72 and 2.35 kcal mol(-1), respectively. Here we report the stability data and 1.7 A resolution crystal structures of both mutant proteins, complexed with the immunosuppressant rapamycin. Both structures show a relatively large response to mutation involving a helical bulge at the mutation site and the loss of a hydrogen bond that anchors a nearby loop. The increased stability of the mutants is probably due to a combination of improved packing and an entropic gain at the mutation site. The structures are almost identical to that of wild-type FKBP12.6, an isoform of FKBP12 that differs by 18 residues, including Trp59, in its sequence. Therefore, the structural difference between the two isoforms can be attributed almost entirely to the identity of residue 59. It is likely that in FKBP12-ligand complexes Trp59 provides added binding energy at the active site at the expense of protein stability, a characteristic common to other proteins. FKBP12 associates with the ryanodine receptor in skeletal muscle (RyR1), while FKBP12.6 selectively binds the ryanodine receptor in cardiac muscle (RyR2). The structural response to mutation suggests that residue 59 contributes to the specificity of binding between FKBP12 isoforms and ryanodine receptors. Study holds ProTherm entries: 15806, 15807, 15808 Extra Details: hydrophobic ligand-binding site; helical bulge; FKBP12; binding energy

Submission Details

ID: AneYvfAF

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:46 p.m.

Version: 1

Publication Details
Fulton KF;Jackson SE;Buckle AM,Biochemistry (2003) Energetic and structural analysis of the role of tryptophan 59 in FKBP12. PMID:12600203
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
1FKK 1995-08-18T00:00:00+0000 2.2 ATOMIC STRUCTURE OF FKBP12, AN IMMUNOPHILIN BINDING PROTEIN
1FKL 1995-08-18T00:00:00+0000 1.7 ATOMIC STRUCTURE OF FKBP12-RAPAYMYCIN, AN IMMUNOPHILIN-IMMUNOSUPPRESSANT COMPLEX
1TCO 1996-08-21T00:00:00+0000 2.5 TERNARY COMPLEX OF A CALCINEURIN A FRAGMENT, CALCINEURIN B, FKBP12 AND THE IMMUNOSUPPRESSANT DRUG FK506 (TACROLIMUS)
3J8H 2014-10-26T00:00:00+0000 3.8 Structure of the rabbit ryanodine receptor RyR1 in complex with FKBP12 at 3.8 Angstrom resolution
5GKY 2016-07-07T00:00:00+0000 3.8 Structure of RyR1 in a closed state (C1 conformer)
5GKZ 2016-07-07T00:00:00+0000 4.0 Structure of RyR1 in a closed state (C3 conformer)
5GL0 2016-07-07T00:00:00+0000 4.2 Structure of RyR1 in a closed state (C4 conformer)
5GL1 2016-07-07T00:00:00+0000 5.7 Structure of RyR1 in an open state
1A7X 1998-03-18T00:00:00+0000 2.0 FKBP12-FK1012 COMPLEX
1B6C 1999-01-13T00:00:00+0000 2.6 CRYSTAL STRUCTURE OF THE CYTOPLASMIC DOMAIN OF THE TYPE I TGF-BETA RECEPTOR IN COMPLEX WITH FKBP12

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
97.2 Peptidyl-prolyl cis-trans isomerase FKBP1A Q62658 FKB1A_RAT
97.2 Peptidyl-prolyl cis-trans isomerase FKBP1A P26883 FKB1A_MOUSE
97.2 Peptidyl-prolyl cis-trans isomerase FKBP1A P18203 FKB1A_BOVIN
100.0 Peptidyl-prolyl cis-trans isomerase FKBP1A P62943 FKB1A_RABIT
100.0 Peptidyl-prolyl cis-trans isomerase FKBP1A P62942 FKB1A_HUMAN