title: Application of free-flow electrophoresis to the purification of trichosanthin from a crude product of acetone fractional precipitation.
abstract: The application of free-flow electrophoresis (FFE) to the purification of trichosanthin (TCS) from a crude product of acetone fractional precipitation was investigated. An electrophoresis technique, combining field step electrophoresis (FSE) and zone electrophoresis (ZE) to a one-step procedure, was optimized until a satisfactory purification factor (1.35), high resolution, and purity (>99%) were achieved. Testing several separation buffer systems revealed that a throughput of 14.2 mg/h can be obtained when the very basic TCS (pI 10.1) was dissolved and electrophoresed in a phosphate buffer system of pH 4. The purity of electrophoresed trichosanthin was proved by a variety of analytical methods, such as sodium dodecyl sulfate (SDS)-gel electrophoresis, capillary isoelectric focusing (CIEF), and sequencing of N- and C-termini. The high purity and large throughput achieved at low cost by using FFE indicates that this method can be employed for TCS purification.
authors.affiliation: Shanghai Institute of Biochemistry, Chinese Academy of Sciences.
authors.forename: J F
authors.initials: JF
authors.lastname: Song
authors.forename: T
authors.initials: T
authors.lastname: Liu
authors.forename: X
authors.initials: X
authors.lastname: Shen
authors.forename: G D
authors.initials: GD
authors.lastname: Wu
authors.forename: Q C
authors.initials: QC
authors.lastname: Xia
mesh_terms: D000096:Acetone / Q000737:chemistry*; D000595:Amino Acid Sequence; D002021:Buffers; D004586:Electrophoresis / Q000295:instrumentation* / Q000379:methods*; D019075:Electrophoresis, Capillary; D004591:Electrophoresis, Polyacrylamide Gel; D004983:Ethanolamines; D005590:Fractional Precipitation; D010446:Peptide Fragments / Q000302:isolation & purification; D010710:Phosphates; D010940:Plant Proteins / Q000302:isolation & purification*; D012967:Sodium Dodecyl Sulfate; D015978:Trichosanthin / Q000302:isolation & purification*
chemical_list: D002021:Buffers; D004983:Ethanolamines; D010446:Peptide Fragments; D010710:Phosphates; D010940:Plant Proteins; D000096:Acetone; D012967:Sodium Dodecyl Sulfate; D015978:Trichosanthin; C009546:triethanolamine