title: Capillary electrophoresis and circular dichroism study of trichosanthin and its mutants.
abstract: The type-I ribosome-inactivating protein trichosanthin (TCS) has a broad spectrum of biological and pharmacological activities, including abortifacient, anti-tumor and anti-human-immunodeficiency-virus (anti-HIV). In this study, circular dichroism (CD) and capillary electrophoresis were used for the first time to study TCS and its two TCS mutants of Y55G TCS (tyrosine 55 converted to glycine) and FYY140-142GSA TCS (tripeptide phenylalanine-tyrosine-tyrosine 140-142 converted to glycine-serine-alanine). The results indicated that the substitution of amino acids changed the secondary structures and the hydrophobility of TCS. Moreover, both Y55G TCS and FYY140-142GSA TCS demonstrated attenuated cytotoxicity and reactive oxygen species (ROS) production in human choriocarcinoma cells (JAR cells) as compared to natural TCS and wild-type TCS. Our results demonstrated the cytotoxicity of TCS on JAR cells and TCS-induced production of ROS might be TCS-conformational related, suggesting that CD and capillary electrophoresis study might throw new insight into the anti-tumor and anti-HIV mechanism of TCS.
authors.affiliation: National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871, China; Molecular and Nano Sciences Laboratory, Department of Physics, Tsinghua University, Beijing 100084, China.
authors.forename: Chun-Yang
authors.initials: CY
authors.lastname: Zhang
authors.forename: Cheng-Cai
authors.initials: CC
authors.lastname: An
authors.forename: Rong-Ying
authors.initials: RY
authors.lastname: Wang
authors.forename: Yi-Xuan
authors.initials: YX
authors.lastname: Gong
authors.forename: Hui
authors.initials: H
authors.lastname: Ma
authors.forename: Die-Yan
authors.initials: DY
authors.lastname: Chen
authors.forename: Zhang-Liang
authors.initials: ZL
authors.lastname: Chen