title: Crystallization and preliminary crystallographic studies of a cysteine protease inhibitor from the human nematode parasite Ascaris lumbricoides.
abstract: The cysteine protease inhibitor from Ascaris lumbricoides, a roundworm that lives in the human intestine, may be involved in the suppression of human immune responses. Here, the molecular cloning, protein expression and purification, preliminary crystallization and crystallographic characterization of the cysteine protease inhibitor from A. lumbricoides are reported. The rod-shaped crystal belonged to space group C2, with unit-cell parameters a = 99.40, b = 37.52, c = 62.92 Å, β = 118.26°. The crystal diffracted to 2.1 Å resolution and contained two molecules in the asymmetric unit.
authors.affiliation: National Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou Science Park, Guangzhou, People's Republic of China.
authors.forename: Sanling
authors.initials: S
authors.lastname: Liu
authors.forename: Jianmei
authors.initials: J
authors.lastname: Dong
authors.forename: Guoqiang
authors.initials: G
authors.lastname: Mei
authors.forename: Guiyun
authors.initials: G
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.forename: Zhong
authors.initials: Z
authors.lastname: Su
authors.forename: Jinsong
authors.initials: J
authors.lastname: Liu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017164:Ascaris lumbricoides / Q000201:enzymology*; D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray / Q000379:methods; D015853:Cysteine Proteinase Inhibitors / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D004058:Diffusion; D004926:Escherichia coli / Q000235:genetics; D015801:Helminth Proteins / Q000737:chemistry*; D057166:High-Throughput Screening Assays; D006358:Hot Temperature; D006801:Humans; D009348:Nematoda / Q000469:parasitology; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D012995:Solubility; D013997:Time Factors; D014169:Transformation, Bacterial; D014961:X-Ray Diffraction
chemical_list: D015853:Cysteine Proteinase Inhibitors; D015801:Helminth Proteins; D011994:Recombinant Proteins