Amino acid sequence analysis, gene construction, cloning, and expression of gelonin, a toxin derived from Gelonium multiflorum.
The plant toxin gelonin is an extremely potent inhibitor of protein synthesis, similar in action to ricin. The mature protein primary sequence was obtained using conventional sequencing techniques. Gelonin was found to be composed of 258 amino acids and contains 21 lysine residues. This toxin shares approximately 33% sequence homology with trichosanthin and ricin A chain. A 774 bp synthetic gene encoding gelonin was synthesized and expressed in E. coli. Recombinant gelonin (approximately 28 kD) expression was monitored and demonstrated by western analysis. Purification and functional activity studies demonstrated that this protein behaves identically to that of the natural product. Recombinant gelonin (RG) thus joins a growing list of recombinant toxins currently available for use in the construction of recombinant immunotoxins composed of gelonin fused to binding domains of antibodies, growth factors, or other cytokines.
Rosenblum
M G
MG
Department of Clinical Immunology and Biological Therapy, University of Texas-M.D. Anderson Cancer Center, Houston 77030, USA.
Kohr
W A
WA
Beattie
K L
KL
Beattie
W G
WG
Marks
W
W
Toman
P D
PD
Cheung
L
L
D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D015870:Gene Expression; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification; D011500:Protein Synthesis Inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000302:isolation & purification; D054789:Ribosome Inactivating Proteins, Type 1; D017386:Sequence Homology, Amino Acid; D014118:Toxins, Biological / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification
D010940:Plant Proteins; D011500:Protein Synthesis Inhibitors; D011994:Recombinant Proteins; D054789:Ribosome Inactivating Proteins, Type 1; D014118:Toxins, Biological; C025674:GEL protein, Gelonium multiflorum