Host limits to accurate human growth hormone production in multiple plant systems.
Human growth hormone (hGH) is not only a valuable recombinant therapeutic protein for hormone deficiency indications, but is also an extensively characterized molecule both from recombinant bacterial systems and as circulating in humans. We describe the characterization of hGH produced in three different plant systems: tobacco cell culture, soy seed, and maize seed. The data indicate highest production in the maize seed system, with continued productivity over multiple generations, and when bred to a new host genotype for improved productivity. Purification indicated significant material of the correct structure from both plant cell culture and maize seed, with maize seed also showing correct activity relative to that produced by Escherichia coli. However, all systems showed some proteolyzed hGH, with data from gel electrophoresis, mass spectrometry, and peptide mapping localizing to a region of the protein also prone to cleavage in some other systems. Together, the data indicate the dependence of recombinant protein accumulation on posttranslational processes in different host systems.
Russell
Douglas A
DA
Agracetus Campus-Monsanto, P.O. Box 620999, Middleton, Wisconsin 53562, USA. doug.russell@syngenta.com
Spatola
Lori A
LA
Dian
Titik
T
Paradkar
Vikram M
VM
Dufield
Dawn R
DR
Carroll
James A
JA
Schlittler
Michael R
MR
D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism; D019382:Human Growth Hormone / Q000096:biosynthesis* / Q000737:chemistry / Q000302:isolation & purification; D006801:Humans; D006868:Hydrolysis; D013058:Mass Spectrometry; D010449:Peptide Mapping; D030821:Plants, Genetically Modified; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000302:isolation & purification; D012639:Seeds / Q000378:metabolism / Q000502:physiology; D013025:Glycine max / Q000378:metabolism*; D014026:Nicotiana / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D014170:Transformation, Genetic; D003313:Zea mays / Q000378:metabolism*
D011994:Recombinant Proteins; D019382:Human Growth Hormone