Isolation of a jadomycin incorporating l-ornithine, analysis of antimicrobial activity and jadomycin reactive oxygen species (ROS) generation in MDA-MB-231 breast cancer cells

Herein, we report the characterization and antimicrobial activity of a previously unreported jadomycin (1) obtained from a culture of S. venezuelae ISP5230 with L-ornithine (Orn). 1 arises from the rearrangement of a putative five-membered ring containing jadomycin incorporating Orn, whereby intramolecular attack of the E-ring carbonyl from the δ-NH2 group of the Orn side chain results in collapse of the oxazolone ring and formation of a stable six-membered lactam. This rearrangement produces a jadomycin with a 3a hemiaminal position that is susceptible to solvolysis. A structure-activity relationship is discussed based on the antimicrobial activity of 1 compared to previously reported jadomycins, providing evidence that the presence of a 3a hemiaminal enhances activity against Gram-positive bacteria. Additionally, assays to quantify reactive oxygen species (ROS) generation and cell viability were performed using a series of nine jadomycins. Compound 1 was found to produce the highest ROS activity and to possess the greatest cytotoxicity against MDA-MB-231 breast cancer cells

Power, expertise and the limits of representative democracy: genetics as scientific progress or political legitimation in carcinogenic risk assessment of pharmaceuticals?

In modern ‘representative’ democratic states, the legitimacy of governments’ actions rests on their publicly declared commitment to protect the interests of their citizens. Regarding the pharmaceutical sector in most democracies, new drug products are developed and marketed by a capitalist industry, whose member firms, via shareholders, have commercial interests in expanding product sales. In those democracies, states have established government agencies to regulate the pharmaceutical industry on behalf of citizens. State legislatures, such as the US Congress and European Parliaments, have charged government drug regulatory agencies with the legal responsibility to protect public health. Yet, this paper argues that government drug regulatory agencies in the EU, Japan, and USA have permitted the pharmaceutical industry to reshape the regulatory guidance for carcinogenic risk assessment of pharmaceuticals in ways that are not techno-scientifically defensible as bases for improved, or even equivalent, protection of public health, compared with the previous techno-regulatory standards. By adopting the industry’s agenda of streamlining carcinogenicity testing in order to accelerate drug development and regulatory review, it is contended that these regulatory agencies have allowed the techno-regulatory standards for carcinogenic risk assessment to be loosened in ways that are presented as scientific progress resulting from new genetics, but for which there is little evidence of progress in public health protection