title: Analysis of the local dynamics of human insulin and a rapid-acting insulin analog by hydrogen/deuterium exchange mass spectrometry.
abstract: Human insulin and insulin lispro (lispro), a rapid-acting insulin analog, have identical primary structures, except for the transposition of a pair of amino acids. This mutation results in alterations in their higher order structures, with lispro dissociating more easily than human insulin. In our previous study performed using hydrogen/deuterium exchange mass spectrometry (HDX/MS), differences were observed in the rates and levels of deuteration among insulin analog products, which were found to be related to their self-association stability. In this study, we carried out peptide mapping of deuterated human insulin and lispro to determine the regions responsible for these deuteration differences and to elucidate the type of structural changes that affect their HDX reactivity. We identified A3-6 and B22-24 as the 2 regions that showed distinct differences in the number of deuterium atoms incorporated between human insulin and lispro. These regions contain residues that are thought to participate in hexamerization and dimerization, respectively. We also determined that over time, the differences in deuteration levels decreased in A3-6, whereas they increased in B22-24, suggesting a difference in the dynamics between these 2 regions. This article is part of a Special Issue entitled: Mass spectrometry in structural biology.
authors.affiliation: Graduate School of Life Science, Hokkaido University, Sapporo, Japan. nakazawa@pharm.hokuai.ac.jp
authors.forename: Shiori
authors.initials: S
authors.lastname: Nakazawa
authors.forename: Joomi
authors.initials: J
authors.lastname: Ahn
authors.forename: Noritaka
authors.initials: N
authors.lastname: Hashii
authors.forename: Kenji
authors.initials: K
authors.lastname: Hirose
authors.forename: Nana
authors.initials: N
authors.lastname: Kawasaki
mesh_terms: D000595:Amino Acid Sequence; D003903:Deuterium / Q000737:chemistry; D041961:Deuterium Exchange Measurement / Q000379:methods*; D006801:Humans; D006859:Hydrogen / Q000737:chemistry; D007328:Insulin / Q000031:analogs & derivatives* / Q000737:chemistry*; D061268:Insulin Lispro / Q000737:chemistry*; D061266:Insulin, Short-Acting / Q000737:chemistry*; D013058:Mass Spectrometry / Q000379:methods*; D056004:Molecular Dynamics Simulation; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry
chemical_list: D007328:Insulin; D061268:Insulin Lispro; D061266:Insulin, Short-Acting; D010455:Peptides; D006859:Hydrogen; D003903:Deuterium