title: Computational study on substrate specificity of a novel cysteine protease 1 precursor from Zea mays.
abstract: Cysteine protease 1 precursor from Zea mays (zmCP1) is classified as a member of the C1A family of peptidases (papain-like cysteine protease) in MEROPS (the Peptidase Database). The 3D structure and substrate specificity of the zmCP1 is still unknown. This study is the first one to build the 3D structure of zmCP1 by computer-assisted homology modeling. In order to determine the substrate specificity of zmCP1, docking study is used for rapid and convenient analysis of large populations of ligand-enzyme complexes. Docking results show that zmCP1 has preference for P1 position and P2 position for Arg and a large hydrophobic residue (such as Phe). Gly147, Gly191, Cys189, and Asp190 are predicted to function as active residues at the S1 subsite, and the S2 subsite contains Leu283, Leu193, Ala259, Met194, and Ala286. SIFt results indicate that Gly144, Arg268, Trp308, and Ser311 play important roles in substrate binding. Then Molecular Mechanics-Poisson-Boltzmann Surface Area (MM-PBSA) method was used to explain the substrate specificity for P1 position of zmCp1. This study provides insights into the molecular basis of zmCP1 activity and substrate specificity.
authors.affiliation: College of Food Science and Engineering, Jilin Agricultural University, Changchun 130118, China. hymanliu@126.com.
authors.forename: Huimin
authors.initials: H
authors.lastname: Liu
authors.affiliation: Engineering Research Center of Edible and Medicinal Fungi, Ministry of Education, Changchun 130118, China. chen71@139.com.
authors.forename: Liangcheng
authors.initials: L
authors.lastname: Chen
authors.affiliation: College of Life Science, Jilin University, Changchun 130023, China. liquan13@mails.jlu.edu.cn.
authors.forename: Quan
authors.initials: Q
authors.lastname: Li
authors.affiliation: College of Food Science and Engineering, Jilin Agricultural University, Changchun 130118, China. minminlhm@126.com.
authors.forename: Mingzhu
authors.initials: M
authors.lastname: Zheng
authors.affiliation: College of Food Science and Engineering, Jilin Agricultural University, Changchun 130118, China. liujs1007@vip.sina.com.
authors.forename: Jingsheng
authors.initials: J
authors.lastname: Liu
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D020134:Catalytic Domain; D057056:Cysteine Proteases / Q000737:chemistry / Q000378:metabolism*; D062105:Molecular Docking Simulation; D008969:Molecular Sequence Data; D010802:Phylogeny; D011498:Protein Precursors / Q000737:chemistry / Q000378:metabolism; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D013379:Substrate Specificity; D003313:Zea mays / Q000145:classification / Q000201:enzymology*
chemical_list: D011498:Protein Precursors; D057056:Cysteine Proteases