title: Localization of the membrane interaction sites of Pal-like protein, HI0381 of Haemophilus influenzae.
abstract: HI0381 of Haemophilus influenzae was investigated by circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy. HI0381 is a 153-residue peptidoglycan-associated outer membrane lipoprotein, and a part of the larger Tol/Pal network. Here, we report its backbone (1)H, (15)N, and (13)C resonance assignments, and secondary structure predictions. About 97% of all of the (1)HN, (15)N, (13)CO, (13)C alpha, and (13)C beta resonances covering 131 non-proline residues of the 134 residue, mature protein, were clarified by sequential and specific assignments. CSI and TALOS analyses revealed that HI0381 contains five alpha-helices and five beta-strands. To characterize the structure of HI0381, the effects of pH and salt concentration were investigated by CD. In addition, the structural changes occurring when HI0381 was in a membranous environment were investigated by comparing its HSQC spectra and CD data in buffer and in DPC micelles; the results showed that helix alpha 4 and strand beta 4 became aligned with the membrane. We conclude that the conformation of HI0381 is affected by the membrane environment, implying that its folded state is directly related to its function.
authors.affiliation: Innovative Drug Research Center for Metabolic and Inflammatory Disease, Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul 151-742, Korea.
authors.forename: Su-Jin
authors.initials: SJ
authors.lastname: Kang
authors.forename: Sung Jean
authors.initials: SJ
authors.lastname: Park
authors.forename: Bong-Jin
authors.initials: BJ
authors.lastname: Lee
mesh_terms: D000429:Alcohol Oxidoreductases / Q000737:chemistry*; D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry*; D002942:Circular Dichroism; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D017433:Protein Structure, Secondary
chemical_list: D001425:Bacterial Outer Membrane Proteins; D008823:Micelles; D000429:Alcohol Oxidoreductases; C022641:Shikimate dehydrogenase