The intestinal fatty acid binding protein: the role of turns in fast and slow folding processes.


Abstract

The intestinal fatty acid binding protein is one of a family of proteins that are composed of two beta-sheets surrounding a large interior cavity into which the ligand binds. Glycine residues occur in many of the turns between adjacent antiparallel beta-strands. In previous work, the effect of replacing these glycine residues with valine has been examined with stopped flow instrumentation using intrinsic tryptophan fluorescence spectroscopy [Kim and Frieden (1998) Protein Sci. 7, 1821-1828]. To resolve the burst phase missing in the stopped flow measurements, these valine mutants have been reexamined with sub-millisecond continuous flow instrumentation. Some of the glycine residues have also been replaced with proline, and the folding reactions of these proline mutants have been compared with those of their valine counterparts. In all cases, the stability of the protein is decreased, but some turns appear to be more critical for final structure stabilization than others. Surprisingly, the rate constants observed for all the mutants measured by sub-millisecond continuous flow methods are quite similar (1400-3000 s(-1)), and in all the mutants, there is a shift in the fluorescence emission maximum from that of the unfolded protein to lower wavelengths, suggesting some collapse of the unfolded state within 200 micros. In contrast to the rate constants observed for the initial folding events measured by the sub-millisecond continuous flow method, the rate constants for the slower phase observed in the stopped flow instrument vary widely for the different mutants. The latter step appears to be related to side chain stabilization rather than secondary structure formation. It is also shown that the ligand binds tightly only to the native protein and not to any intermediate forms. Study holds ProTherm entries: 14966, 14967, 14968, 14969, 14970, 14971 Extra Details: antiparallel beta-strands; turn; glycine residues; secondary structure formation

Submission Details

ID: QACtsL3p

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:45 p.m.

Version: 1

Publication Details
Chattopadhyay K;Zhong S;Yeh SR;Rousseau DL;Frieden C,Biochemistry (2002) The intestinal fatty acid binding protein: the role of turns in fast and slow folding processes. PMID:11900547
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
1SA8 2004-06-08 THE NMR STRUCTURE OF A STABLE AND COMPACT ALL-beta-SHEET VARIANT OF INTESTINAL FATTY ACID-BINDING PROTEIN
1URE 1997-03-12 NMR STRUCTURE OF INTESTINAL FATTY ACID-BINDING PROTEIN COMPLEXED WITH PALMITATE, 20 STRUCTURES
1A57 1998-05-27 THE THREE-DIMENSIONAL STRUCTURE OF A HELIX-LESS VARIANT OF INTESTINAL FATTY ACID BINDING PROTEIN, NMR, 20 STRUCTURES
1AEL 1997-04-01 NMR STRUCTURE OF APO INTESTINAL FATTY ACID-BINDING PROTEIN, 20 STRUCTURES
1T8V 2005-10-04 The NMR structure of d34a i-fabp: implications for the determinants of ligand binding stoichiometry
1IFC 1994-01-31 1.19 REFINEMENT OF THE STRUCTURE OF RECOMBINANT RAT INTESTINAL FATTY ACID-BINDING APOPROTEIN AT 1.2 ANGSTROMS RESOLUTION
1ICM 1994-01-31 1.5 ESCHERICHIA COLI-DERIVED RAT INTESTINAL FATTY ACID BINDING PROTEIN WITH BOUND MYRISTATE AT 1.5 A RESOLUTION AND I-FABPARG106-->GLN WITH BOUND OLEATE AT 1.74 A RESOLUTION
3AKN 2011-07-20 1.6 X-ray structure of iFABP from human and rat with bound fluorescent fatty acid analogue
1ICN 1994-01-31 1.74 ESCHERICHIA COLI-DERIVED RAT INTESTINAL FATTY ACID BINDING PROTEIN WITH BOUND MYRISTATE AT 1.5 A RESOLUTION AND I-FABPARG106-->GLN WITH BOUND OLEATE AT 1.74 A RESOLUTION
1IFB 1992-01-15 1.96 REFINED APOPROTEIN STRUCTURE OF RAT INTESTINAL FATTY ACID BINDING PROTEIN PRODUCED IN ESCHERICHIA COLI
2IFB 1992-01-15 2.0 CRYSTAL STRUCTURE OF RAT INTESTINAL FATTY-ACID-BINDING PROTEIN. REFINEMENT AND ANALYSIS OF THE ESCHERICHIA COLI-DRIVED PROTEIN WITH BOUND PALMITATE
1DC9 2000-03-20 2.1 PROPERTIES AND CRYSTAL STRUCTURE OF A BETA-BARREL FOLDING MUTANT, V60N INTESTINAL FATTY ACID BINDING PROTEIN (IFABP)

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
92.4 Fatty acid-binding protein, intestinal P55050 FABPI_MOUSE
100.0 Fatty acid-binding protein, intestinal P02693 FABPI_RAT