A partially unfolded structure of the alkaline-denatured state of pepsin and its implication for stability of the zymogen-derived protein.


Abstract

Pepsin, a gastric aspartic proteinase, is a zymogen-derived protein that undergoes irreversible alkaline denaturation at pH 6-7. Detailed knowledge of the structure of the alkaline-denatured state is an important step in understanding the mechanism of the formation of the active enzyme. An extensive analysis of the denatured state at pH 8.0 was performed using a variety of techniques including (1)H nuclear magnetic resonance spectroscopy and solution X-ray scattering. This analysis indicates that the denatured state under these conditions has a compact and globular conformation with a substantial amount of secondary and tertiary structures. The data suggest that this partially structured species has a highly folded region and a flexible region. The NMR measurements suggest that the folded region contains His53 and is located at least partly in the N-terminal lobe of the protein. The alkaline-denatured state experiences a further reversible denaturation step at higher pH or on heating; the midpoints of the unfolding transition are pH 11.5 (at 25 degrees C) and 53.1 degrees C (at pH 8.0), respectively. The present findings suggest that the proteolytic processing of pepsinogen has substantially modified the ability of the protein to fold, such that its folding process cannot progress beyond the partially folded intermediate of pepsin. Study holds ProTherm entries: 7962, 7963 Extra Details: globular conformation; tertiary structures; alkaline-denatured,state; partially folded intermediate

Submission Details

ID: ru6jkcDi

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:35 p.m.

Version: 1

Publication Details
Konno T;Kamatari YO;Tanaka N;Kamikubo H;Dobson CM;Nagayama K,Biochemistry (2000) A partially unfolded structure of the alkaline-denatured state of pepsin and its implication for stability of the zymogen-derived protein. PMID:10747810
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
3PSG 1993-01-15 1.65 THE HIGH RESOLUTION CRYSTAL STRUCTURE OF PORCINE PEPSINOGEN
2PSG 1992-10-15 1.8 REFINED STRUCTURE OF PORCINE PEPSINOGEN AT 1.8 ANGSTROMS RESOLUTION
4PEP 1990-04-15 1.8 THE MOLECULAR AND CRYSTAL STRUCTURES OF MONOCLINIC PORCINE PEPSIN REFINED AT 1.8 ANGSTROMS RESOLUTION
3PEP 1990-04-15 2.3 REVISED 2.3 ANGSTROMS STRUCTURE OF PORCINE PEPSIN. EVIDENCE FOR A FLEXIBLE SUBDOMAIN
5PEP 1990-07-15 2.34 X-RAY ANALYSES OF ASPARTIC PROTEASES. II. THREE-DIMENSIONAL STRUCTURE OF THE HEXAGONAL CRYSTAL FORM OF PORCINE PEPSIN AT 2.3 ANGSTROMS RESOLUTION
1F34 2001-02-01 2.45 CRYSTAL STRUCTURE OF ASCARIS PEPSIN INHIBITOR-3 BOUND TO PORCINE PEPSIN
1PSA 1994-01-31 2.9 STRUCTURE OF A PEPSIN(SLASH)RENIN INHIBITOR COMPLEX REVEALS A NOVEL CRYSTAL PACKING INDUCED BY MINOR CHEMICAL ALTERATIONS IN THE INHIBITOR
1YX9 2005-05-24 3.0 Effect of Dimethyl Sulphoxide on the crystal structure of Porcine Pepsin

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Pepsin A P00791 PEPA_PIG