The folding of maltose-binding protein, a periplasmic protein in Escherichia coli, was shown to proceed through the same rate-limiting step whether folding occurred in the cell under physiological conditions or in vitro in the absence of other proteins. Four species of maltose-binding protein containing aminoacyl substitutions identified as decreasing the rate of folding of the protein in vivo were purified, and their denaturant-induced folding transitions were analyzed by monitoring the intrinsic fluorescence of tryptophan. In all four cases the rate of folding in vitro was slower than that of the wild-type maltose-binding protein; thus the same step determines the rate of folding in vivo and in vitro. Furthermore, examination of the three-dimensional structure of maltose-binding protein as determined by x-ray crystallography (F. Quiocho, personal communication; Spurlino, J. C., Lu, G.-Y., and Quiocho, F. A. (1991) J. Biol. Chem. 266, 5202-5219) indicates that all 4 of the residues identified as crucial to folding lie in one structural element of the native protein. We conclude that the rate-limiting step both in vivo and in vitro involves formation of this element of structure. Study holds ProTherm entries: 5226, 5227, 5228, 5229, 5230, 5231, 5232 Extra Details: periplasmic protein; rate-limiting step; folding transitions;,structural element
ID: ADyrbQZt3
Submitter: Connie Wang
Submission Date: April 24, 2018, 8:29 p.m.
Version: 1
Colors: | D | E | R | H | K | S | T | N | Q | A | V | I | L | M | F | Y | W | C | G | P |
---|
Percent Identity | Matching Chains | Protein | Accession | Entry Name |
---|---|---|---|---|
100.0 | Maltose-binding periplasmic protein | P0AEY0 | MALE_ECO57 | |
100.0 | Maltose-binding periplasmic protein | P0AEX9 | MALE_ECOLI | |
94.3 | Maltose-binding periplasmic protein | P19576 | MALE_SALTY | |
93.9 | Maltose-binding periplasmic protein | P18815 | MALE_KLEAE | |
90.7 | Maltose-binding periplasmic protein | P41130 | MALE_PHOLU |