title: [Purification and characterization of trichokirin-S1, a novel ribosome-inactivating peptide from seeds of Trichosanthes kirilowii].
abstract: A novel peptide from the seeds of Trichosanthes kirilowii, trichokirin-S1, was purified by extraction of protein body, ammonia sulfate precipitation, Blue-gel affinity chromatography, FPLC Mono S ion exchange chromatography and Superose12 gel filtration chromatography. Its molecular weight was determined to be 11,426 by MALDI-TOF MS analysis. Its reaction mechanism to inactive ribosome was the same as that of the ribosome-inactivating protein trichosanthin, a rRNA N-glycosidase. The purified trichokirin-S1 showed a strong inhibitory activity on protein synthesis in cell-free rabbit reticulocyte lysate system, with IC(50) of 0.7 nmol/L. Therefore, trichokirin-S1 may be a promising and efficient toxin moiety of immunotoxins.
authors.affiliation: Key Laboratory of Proteomics Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Xin-Xiu
authors.initials: XX
authors.lastname: Yang
authors.forename: Wei-Guo
authors.initials: WG
authors.lastname: Hu
authors.forename: Hen-Chuan
authors.initials: HC
authors.lastname: Xia
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.forename: Zu-Chuan
authors.initials: ZC
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002474:Cell-Free System; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D010940:Plant Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D014176:Protein Biosynthesis / Q000187:drug effects; D011817:Rabbits; D051381:Rats; D012270:Ribosomes / Q000187:drug effects / Q000378:metabolism; D012639:Seeds / Q000737:chemistry*; D020539:Sequence Analysis, Protein; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D029778:Trichosanthes / Q000737:chemistry*
chemical_list: D010936:Plant Extracts; D010940:Plant Proteins