Improved metabolic action of a bacterial lysine decarboxylase gene in tobacco hairy root cultures by its fusion to a rbcS transit peptide coding sequence

• Published in: Transgenic research 1996-05, Vol.5 (3), p.193-201
• Main Authors: HERMINGHAUS, S, THOLL, D, RÜGENHAGEN, C, FECKER, L. F, LEUSCHNER, C, BERLIN, J
• Format: Article
• Language: English
• Subjects: Anabasine - metabolism; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Biological and medical sciences; Biotechnology; Cadaverine - metabolism; Carboxy-Lyases - genetics; Carboxy-Lyases - metabolism; Fundamental and applied biological sciences. Psychology; Genetic engineering; Genetic technics; Kanamycin Resistance - genetics; Kinetics; Methods. Procedures. Technologies; Mosaic Viruses - genetics; Nicotiana - cytology; Nicotiana tabacum; Organ Culture Techniques; Plant Proteins - genetics; Plant Roots - metabolism; Plants, Genetically Modified; Plants, Toxic; Promoter Regions, Genetic; Protein Sorting Signals - genetics; Protein Sorting Signals - metabolism; Recombinant Fusion Proteins - metabolism; Ribulose-Bisphosphate Carboxylase - genetics; Transgenic animals and transgenic plants; Transgenic plants
• ISSN: 0962-8819; 1573-9368
• DOI: 10.1007/BF01969709

The gene of a bacterial lysine decarboxylase (ldc) fused to a rbcS transit peptide coding sequence (tp), and under the control of the CaMV 35S promoter, was expressed in hairy root cultures of Nicotiana tabacum. The fusion of the ldc to the targeting signal sequence improved the performance of the bacterial gene in the plant cells in many respects. Nearly all transgenic hairy root cultures harbouring the 35S-tp-ldc gene contained distinctly higher lysine decarboxylase activity (from 1.5 to 30 pkat LDC per mg protein) than those which had been transformed with constructs in which the gene had been directly cloned behind the CaMV 35S promoter. The higher enzyme activity led to the accumulation of up to 0.7% cadaverine on a dry mass basis. In addition, part of the cadaverine pool was used for increased biosynthesis of anabasine, an alkaloid which was hardly detectable in control cultures. The best line contained anabasine levels of 0.5% dry mass, which could be further be enhanced by feeding of lysine.