title: Structure-Function Relationship of a Novel PR-5 Protein with Antimicrobial Activity from Soy Hulls.
abstract: An alkaline isoform of the PR-5 protein (designated GmOLPc) has been purified from soybean hulls and identified by MALDI-TOF/TOF-MS. GmOLPc effectively inhibited in vitro the growth of Phytophthora soja spore and Pseudomonas syringae pv glycinea. The antimicrobial activity of GmOLPc should be mainly ascribed to its high binding affinity with vesicles composed of DPPG, (1,3)-β-D-glucans, and weak endo-(1,3)-β-D-glucanase activity. From the 3D models, predicted by the homology modeling, GmOLPc contains an extended negatively charged cleft. The cleft was proved to be a prerequisite for endo-(1,3)-β-D-glucanase activity. Molecular docking revealed that the positioning of linear (1,3)-β-D-glucans in the cleft of GmOLPc allowed an interaction with Glu83 and Asp101 that were responsible for the hydrolytic cleavage of glucans. Interactions of GmOLPc with model membranes indicated that GmOLPc possesses good surface activity which could contribute to its antimicrobial activity, as proved by the behavior of perturbing the integrity of membranes through surface hydrophobic amino acid residues (Phe89 and Phe94).
authors.affiliation: Research and Development Center of Food Proteins, Department of Food Science and Technology, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Chun
authors.initials: C
authors.lastname: Liu
authors.affiliation: Research and Development Center of Food Proteins, Department of Food Science and Technology, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Fenfen
authors.initials: F
authors.lastname: Cheng
authors.affiliation: Research and Development Center of Food Proteins, Department of Food Science and Technology, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Yingen
authors.initials: Y
authors.lastname: Sun
authors.affiliation: College of Plant Protection, Nanjing Agricultural University , Nanjing 210095, People's Republic of China.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Ma
authors.affiliation: Research and Development Center of Food Proteins, Department of Food Science and Technology, South China University of Technology , Guangzhou 510640, People's Republic of China.|State Key Laboratory of Pulp and Paper Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Xiaoquan
authors.initials: X
authors.lastname: Yang
mesh_terms: D000595:Amino Acid Sequence; D000890:Anti-Infective Agents / Q000737:chemistry* / Q000494:pharmacology*; D062105:Molecular Docking Simulation; D008969:Molecular Sequence Data; D010838:Phytophthora / Q000187:drug effects / Q000254:growth & development; D044224:Pseudomonas syringae / Q000187:drug effects / Q000254:growth & development; D017386:Sequence Homology, Amino Acid; D030262:Soybean Proteins / Q000737:chemistry* / Q000494:pharmacology*; D013025:Glycine max / Q000737:chemistry*; D013329:Structure-Activity Relationship
chemical_list: D000890:Anti-Infective Agents; D030262:Soybean Proteins
keywords: antimicrobial protein; endo-(1,3)-β-d-glucanase activity; soy hulls; structure−function relationship; surface activity