Root cultures

Supplying sufficient oxygen can be difficult when dealing with differentiated plant tissues such as root cultures that can reach lengths of several decimeters and can be highly branched and complex struc-... 

Mukundan, U. et al., pH-mediated release of betalains from transformed root cultures of Beta vulgaris L., Appl. Microbiol. BiotechnoL, 50, 241, 1998. 

Decarboxybetaiudin, the glucoside of which was reported recently in hairy root cultures of yellow beet, may be synthesized from dopamine. Two further alternatives were proposed earlier. While Minale and co-workers subjected betanin... 

Trinitrotoluene (TNT) is reduced by the aquatic plant Myriophyllum spicatum to ami-nodinitrotoluenes (Pavlostathis et al. 1998) and, in axenic root cultures of Catharanthus roseus, the initial metabolites 2-amino-4,6-dinitrotoluene and 4-amino-2,6-dintrotoluene... 

Foreign Protein Expression Using Plant Cell Suspension and Hairy Root Cultures... 

The presence of foreign protein in the medium of plant cultures does not necessarily mean that all or even most of the product can be recovered from the medium. In many expression systems where an appropriate signal sequence has been used, considerable amounts of foreign protein remain within the plant cells and/or tissues. For example, in a comparison of IgG antibody production in tobacco cell suspension and hairy root cultures, a maximum of 72% of the total antibody was found in the medium of the suspension cultures whereas only 26% was found in the medium of the hairy root cultures [17]. This result could indicate that secretion and/or transport across the cell wall was slower in the hairy roots alternatively, it could indicate poorer stability of the secreted protein in the hairy root medium. If foreign proteins are to be purified from the medium, improved secretion and extracellular product stability are desirable. 

Increasing concentrations of PVP 360,000 up to 1.0 g L 1 improved antibody accumulation in hairy root culture medium however, above this concentration there was no further increase in antibody levels [19]. Addition of PVP after extracellular foreign protein levels had decreased during plant suspension culture did not result in a recovery of the protein [66]. 

Supplementation of Gamborg s B5 medium with 0.1% KN03 (in addition to the 0.25% KN03 usually present in B5 medium) resulted in a significant increase in antibody levels in tobacco hairy root cultures [19]. The antibody concentration in the medium increased 2.8-fold and the total antibody accumulation increased by 90% relative to cultures without added nitrate. 

In transgenic hairy root cultures, the concentration of IgG antibody in the biomass increased by 52% relative to the levels obtained under air when the roots were cultured at a dissolved oxygen tension of 150% air saturation [17]. Compared with root cultures grown at 50% air saturation, which is a realistic operating dissolved oxygen tension in poorly mixed, large-scale root reactors, oxygen enrichment to 150% air saturation improved total antibody accumulation 2.9-fold. 

R. Wongsamuth, P. M. Doran, Hairy roots as an expression system for production of antibodies, in Hairy Roots Culture and Applications, ed. P. M. Doran, Harwood Academic, Amsterdam, 1997, 89-97. 

RicinB fused to green fluorescent protein (GFP) Tobacco leaf and hairy root culture GFP-specific IgG present in serum IgA in semm and fecal matter. 10... 

Wang JW, Tan RX. (2002) Artemisinin production in Artemisia annua hair root cultures with improved growth by altering the nitrogen source in the medium. Biotechnol Lett 24 1153-1156. 

Synthesis of scopolamine (Fig. 4), a tropane alkaloid of known anticholinergic properties, was induced hy fivefold in hairy root cultures of Atropa belladonna overexpressing hyoscianine 6[3-hydroxilase. ... 

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