Comparison of the molten globule states of thermophilic and mesophilic alpha-amylases.


Abstract

In recent years great interest has been generated in the process of protein folding, and the formation of intermediates during the folding process has been proven with new experimental strategies. In the present work, we have examined the molten globule state of Bacillus licheniformis alpha-amylase (BLA) by intrinsic fluorescence and circular dichroism spectra, 1-anilino naphthalene-8-sulfonate (ANS) binding and proteolytic digestion by pepsin, for comparison to its mesophilic counterpart, Bacillus amyloliquefaciens alpha-amylase (BAA). At pH 4.0, both enzymes acquire partially folded state which show characteristics of molten globule state. They unfold in such a way that their hydrophobic surfaces are exposed to a greater extent compared to the native forms. Chemical denaturation studies by guanidine hydrochloride and proteolytic digestion with pepsin show that molten globule state of BLA is more stable than from BAA. Results from gel filtration indicate that BAA has the same compactness at pH 4.0 and 7.5. However, molten globule state of BLA is less compact than its native state. The effects of polyols such as trehalose, sorbitol and glycerol on refolding of enzymes from molten globule to native state were also studied. These polyols are effective on refolding of mesophilic alpha-amylase but only slightly effect on BLA refolding. In addition, the folding pathway and stability of intermediate state of the thermophilic and the mesophilic alpha-amylases are discussed. Study holds ProTherm entries: 20572, 20573 Extra Details: alpha-amylase; Molten globule states; Stability; Folding pathway; Aggregation

Submission Details

ID: dDrcykHq

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:52 p.m.

Version: 1

Publication Details
Shokri MM;Khajeh K;Alikhajeh J;Asoodeh A;Ranjbar B;Hosseinkhani S;Sadeghi M,Biophys. Chem. (2006) Comparison of the molten globule states of thermophilic and mesophilic alpha-amylases. PMID:16516372
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
3BH4 2008-12-09 1.4 High resolution crystal structure of Bacillus amyloliquefaciens alpha-amylase
1E43 2001-06-21 1.7 Native structure of chimaeric amylase from B. amyloliquefaciens and B. licheniformis at 1.7A
1VJS 1997-03-12 1.7 STRUCTURE OF ALPHA-AMYLASE PRECURSOR
1OB0 2003-01-30 1.83 Kinetic stabilization of Bacillus licheniformis alpha-amylase through introduction of hydrophobic residues at the surface
1BLI 1999-03-23 1.9 BACILLUS LICHENIFORMIS ALPHA-AMYLASE
1E3X 2001-06-21 1.9 Native structure of chimaeric amylase from B. amyloliquefaciens and B. licheniformis at 1.92A
1E3Z 2001-06-21 1.93 Acarbose complex of chimaeric amylase from B. amyloliquefaciens and B. licheniformis at 1.93A
1BPL 1996-08-17 2.2 GLYCOSYLTRANSFERASE
1E40 2001-06-21 2.2 Tris/maltotriose complex of chimaeric amylase from B. amyloliquefaciens and B. licheniformis at 2.2A

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
197.4 A,B GLYCOSYLTRANSFERASE P06278 AMY_BACLI
100.0 Alpha-amylase P00692 AMY_BACAM