title: Acidic pH enhances structure and structural stability of the capsid protein of hepatitis E virus.
abstract: Hepatitis E virus (HEV) is enterically transmitted and endemic to tropical areas of the world. The major capsid protein of HEV is pORF2 ( approximately 74 kDa), encoded by open reading frame 2 (ORF2). When expressed in insect cells, it is processed into a approximately 55 kDa form (n-pORF2). We also generated a mutant, m-pORF2, lacking a C-terminal hydrophobic region shown earlier to be required for its homo-oligomerization. Circular dichroism was used to measure the secondary structure and stability of these proteins as a function of pH and temperature. With decreasing pH both proteins acquired increasing alpha-helicity and thermal stability in terms of midpoint of denaturation and the Gibbs energy change.
authors.affiliation: Department of Biosciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Zafrullah
authors.forename: Zenab
authors.initials: Z
authors.lastname: Khursheed
authors.forename: Sushma
authors.initials: S
authors.lastname: Yadav
authors.forename: Deepak
authors.initials: D
authors.lastname: Sahgal
authors.forename: Shahid
authors.initials: S
authors.lastname: Jameel
authors.forename: Faizan
authors.initials: F
authors.lastname: Ahmad
mesh_terms: D000818:Animals; D016367:Baculoviridae / Q000235:genetics; D036022:Capsid Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D002460:Cell Line; D002942:Circular Dichroism; D006023:Glycoproteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D016752:Hepatitis E virus / Q000737:chemistry*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D009036:Moths / Q000166:cytology; D011489:Protein Denaturation; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D013816:Thermodynamics
chemical_list: D036022:Capsid Proteins; D006023:Glycoproteins; D011994:Recombinant Proteins