Volume 4 Issue 2
Engineered Production of Tryprostatins in E. coli through Reconstitution of a Partial ftm Biosynthetic Gene Cluster fromAspergillus sp.
Gopitkumar R Shah# Shane R. Wesener# and Yi-Qiang Cheng*
Tryprostatin A and B are indole alkaloid-based fungal products that inhibit mammalian cell cycle at the G2/M phase. They are biosynthetic intermediates of fumitremorgins produced by a complex pathway involving a nonribosomal peptide synthetase (FtmA), a prenyltransferase (FtmB), a cytochrome P450 hydroxylase (FtmC), an O-methyltransferase (FtmD), and several additional enzymes.
Synthesis of Selenium Nanoparticles by Geobacillus wiegelii strain GWE1 Isolated from a Drying Oven
Muñoz-Ibacache SA*, Correa-Llantén, DN*, Blamey, JM*
Microorganisms play an important role absorbing and accumulating metals from their environments. In some cases this process leads to the formation of well-defined metallic nanoscale particles. These biologically synthesized nanoparticles differ from the chemically produced in their physical properties and stability, opening additional technological opportunities for their use. In this study, the thermophilic bacterium Geobacillus wiegelii strain GWE1 was able to produce selenium nanoparticles. Cultures exposed to Na2SeO3 turned from colourless into an intense red colour. This is indicative of salt reduction confirming the presence of elemental selenium. The use of 5% polyvinylpyrrolidone (PVP) in the culture medium reduced the size of the nanoparticles from 250 nm to 120 nm (52% smaller).