title: Structural characterization of MG and pre-MG states of proteins by MD simulations, NMR, and other techniques.
abstract: Almost all proteins fold via a number of partially structured intermediates such as molten globule (MG) and pre-molten globule states. Understanding the structure of these intermediates at atomic level is often a challenge, as these states are observed under extreme conditions of pH, temperature, and chemical denaturants. Furthermore, several other processes such as chemical modification, site-directed mutagenesis (or point mutation), and cleavage of covalent bond of natural proteins often lead to MG like partially unfolded conformation. However, the dynamic nature of proteins in these states makes them unsuitable for most structure determination at atomic level. Intermediate states studied so far have been characterized mostly by circular dichroism, fluorescence, viscosity, dynamic light scattering measurements, dye binding, infrared techniques, molecular dynamics simulations, etc. There is a limited amount of structural data available on these intermediate states by nuclear magnetic resonance (NMR) and hence there is a need to characterize these states at the molecular level. In this review, we present characterization of equilibrium intermediates by biophysical techniques with special reference to NMR.
authors.affiliation: a Centre for Interdisciplinary Research in Basic Sciences , Jamia Millia Islamia , Jamia Nagar, New Delhi - 110025 , India.
authors.forename: Abdullah
authors.initials: A
authors.lastname: Naiyer
authors.forename: Md Imtaiyaz
authors.initials: MI
authors.lastname: Hassan
authors.forename: Asimul
authors.initials: A
authors.lastname: Islam
authors.forename: Monica
authors.initials: M
authors.lastname: Sundd
authors.forename: Faizan
authors.initials: F
authors.lastname: Ahmad
mesh_terms: D041961:Deuterium Exchange Measurement; D057446:Hydrodynamics; D056004:Molecular Dynamics Simulation; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods; D066329:Protein Aggregates; D011489:Protein Denaturation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry*; D013816:Thermodynamics; D014867:Water / Q000737:chemistry*
chemical_list: D066329:Protein Aggregates; D011506:Proteins; D014867:Water
keywords: MD simulation; molten globule; nuclear magnetic resonance; pre-molten globule; protein denaturation; protein folding; thermodynamic stability