title: CD and NMR investigation of collagen peptides mimicking a pathological Gly-Ser mutation and a natural interruption in a similar highly charged sequence context.
abstract: Even a single Gly substitution in the triple helix domain of collagen leads to pathological conditions while natural interruptions are suggested to play important functional roles. Two peptides-one mimicking a pathological Gly-Ser substitution (ERSEQ) and the other one modeling a similar natural interruption sequence (DRSER)-are designed to facilitate the comparison for elucidating the molecular basis of their different biological roles. CD and NMR investigation of peptide ERSEQ indicates a reduction of the thermal stability and disruption of hydrogen bonding at the Ser mutation site, providing a structural basis of the OI disease resulting from the Gly-Ser mutation in the highly charged RGE environment. Both CD and NMR real-time folding results indicate that peptide ERSEQ displays a comparatively slower folding rate than peptide DRSER, suggesting that the Gly-Ser mutation may lead to a larger interference in folding than the natural interruption in a similar RSE context. Our studies suggest that unlike the rigid GPO environment, the abundant R(K)GE(D) motif may provide a more flexible sequence environment that better accommodates mutations as well as interruptions, while the electrostatic interactions contribute to its stability. These results shed insight into the molecular features of the highly charged motif and may aid the design of collagen biomimetic peptides containing important biological sites.
authors.affiliation: Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, People's Republic of China.
authors.forename: Xiuxia
authors.initials: X
authors.lastname: Sun
authors.affiliation: Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, People's Republic of China.
authors.forename: Songqing
authors.initials: S
authors.lastname: Liu
authors.affiliation: Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, People's Republic of China.
authors.forename: Wenyuan
authors.initials: W
authors.lastname: Yu
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, People's Republic of China.
authors.forename: Shaoru
authors.initials: S
authors.lastname: Wang
authors.affiliation: Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, People's Republic of China.
authors.forename: Jianxi
authors.initials: J
authors.lastname: Xiao
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D002942:Circular Dichroism; D003094:Collagen / Q000737:chemistry / Q000235:genetics*; D005998:Glycine / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D006860:Hydrogen Bonding; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D010455:Peptides / Q000737:chemistry / Q000235:genetics; D017354:Point Mutation; D017510:Protein Folding; D055550:Protein Stability; D017433:Protein Structure, Secondary; D012694:Serine / Q000737:chemistry / Q000235:genetics; D013696:Temperature
chemical_list: D010455:Peptides; D012694:Serine; D003094:Collagen; D005998:Glycine
keywords: CD; NMR; collagen; interruption; mutation