Biochemistry & Molecular Biology

摘要

Practicing recombinant DNA technology has shown great potential to decrease both the cost and the environmental impact of developing important prenyl-based drugs such as the anti-malarial artemisinin and tumor-suppressor Taxol. For reasons not fully understood, progress has been limited by the decreased cell growth of bacterial hosts used to produce these drugs. The cause of death is suspected to be toxicity of isoprenoid precursors. We studied the effects of decreasing the levels of the putative toxic compounds, DMAPP and IPP, by expressing an isoprene synthase from poplar in E. coli. As this enzyme uses DMAPP as a substrate to produce the volatile and releasable isoprene, we hypothesize that its activity could be used to relieve the cytotoxicity. The isoprene synthase expression was varied and paired with increased flux through a heterologous isoprenoid pathway in order to test the hypothesis and examine the influence of intermediate levels on cytotoxicity.