Terminal olefins (1-alkenes) are natural products that have important industrial applications as both fuels and chemicals. However, their biosynthesis has been largely unexplored. We describe a group of bacteria, Jeotgalicoccus spp.
View Article and Find Full Text PDFAlkanes, the major constituents of gasoline, diesel, and jet fuel, are naturally produced by diverse species; however, the genetics and biochemistry behind this biology have remained elusive. Here we describe the discovery of an alkane biosynthesis pathway from cyanobacteria. The pathway consists of an acyl-acyl carrier protein reductase and an aldehyde decarbonylase, which together convert intermediates of fatty acid metabolism to alkanes and alkenes.
View Article and Find Full Text PDFBioethanol and plant oil-derived biodiesel are generally considered first generation biofuels. Recognizing their apparent disadvantages, scientists and engineers are developing more sustainable and economically feasible second generation biofuels. The new microbial fuels summarized here have great potential to become viable replacements or at least supplements of petroleum-derived liquid transportation fuels.
View Article and Find Full Text PDFNatural and semisynthetic rifamycins are clinically important inhibitors of bacterial DNA-dependent RNA polymerase. Although the polyketide-nonribosomal peptide origin of the naphthalene core of rifamycin B is well established, the absolute and relative configuration of both stereocenters introduced by the first polyketide synthase module is obscured by aromatization of the naphthalene ring. To decode the stereochemistry of the rifamycin polyketide precursor, we synthesized all four diastereomers of the biosynthetic substrate for module 2 of the rifamycin synthetase in the form of their N-acetylcysteamine (SNAC) thioester.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
August 2003
Ansamycins such as rifamycin, ansamitocin, and geldanamycin are an important class of polyketide natural products. Their biosynthetic pathways are especially complex because they involve the formation of 3-amino-5-hydroxybenzoic acid (AHBA) followed by backbone assembly by a hybrid nonribosomal peptide synthetase/polyketide synthase. We have reconstituted the ability to synthesize 2,6-dimethyl-3,5,7-trihydroxy-7-(3'-amino-5'-hydroxyphenyl)-2,4-heptadienoic acid (P8/1-OG), an intermediate in rifamycin biosynthesis, in an extensively manipulated strain of Escherichia coli.
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