title: Three-dimensional structure and mimetic-membrane association of consensus 11-amino-acid motif from soybean LEA3 protein.
abstract: The occurrence of a highly conserved 11-mer repeating motif in the primary sequence is a major characteristic of group 3 late embryogenesis abundant (LEA3) proteins, which are strongly associated with abiotic stress tolerance of the plants. In this study, the three-dimensional structure, mimetic membrane association, and salt effect for consensus 11-mer motif from soybean PM2 protein (LEA3) were investigated in sodium dodecyl sulfate (SDS) micelles by NMR techniques. It was shown that the 11-mer motif was disordered in aqueous solution, but adopted an α-helix in SDS micelles. NMR diffusion measurements demonstrated that the 11-mer motif was associated with SDS micelles. Paramagnetic quenching NMR experiments further revealed the orientation of the 11-mer motif with respect to the mimetic membrane: the ordered N-terminal segment was inserted into the mimetic membrane, and the disordered C-terminal segment was exposed to water. In addition, salt addition could not change the secondary structure of the 11-mer motif, but might slightly alter the relative spatial position of some N-terminal residue atoms. These results implied that the 11-mer motif would take an important role in structural plasticity and membrane stabilization for LEA3 proteins.
authors: State Key Laboratory of Rare Earth Resource Utilization, and National Analytical Research Center of Electrochemistry and Spectroscopy, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China.
authors: Rong
authors: R
authors: Xue
authors: Yun
authors: Y
authors: Liu
authors: Yizhi
authors: Y
authors: Zheng
authors: Yijie
authors: Y
authors: Wu
authors: Xiaojing
authors: X
authors: Li
authors: Fengkui
authors: F
authors: Pei
authors: Jiazuan
authors: J
authors: Ni
mesh_terms: D000595:Amino Acid Sequence; D032921:Consensus; D008823:Micelles; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D013025:Glycine max
chemical_list: D008823:Micelles; D012967:Sodium Dodecyl Sulfate