BIOL 58 |
| The antibiotic Lincomycin is synthesized via a multi-step pathway native to the bacterium Streptomyces lincolnensis. While the gene cluster responsible for the lincomycin biosynthetic pathway is known, the enzymes show strikingly little homology to any proteins of known function. Mechanistic study of these phylogentically unique enzymes will likely yield interesting new insights for enzymology, while increasing our understanding of antibiotic synthesis within Streptomycetes. Lincomycin is composed of two separate biosynthetic pieces, mainly an amino acid moiety, propylhygric acid (PHA), and a sugar moiety, methylthiolincosamide (MTL). The first two steps in the biosynthesis of propylhygric acid from tyrosine involve hydroxylation of tyrosine to 3,4-dihydroxyphenylalanine (L-DOPA), followed by extradiol ring cleavage of the dihydroxylated aromatic ring. This poster describes the in vivo enzymatic activity, overexpression, and purification of the putative tyrosine hydroxylase, as well as evidence to support the presence of an iron-sulfur cluster bound by the enzyme. Finally, we also report the purification and kinetic characterization of the non-heme iron dependent dioxygenase responsible for extradiol cleavage of 3,4-dihydroxyphenylalanine. |
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Frontiers in Chemical Biology
5:00 PM-7:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Biological Chemistry |