title: Discovery of parallel pathways of kanamycin biosynthesis allows antibiotic manipulation.
abstract: Kanamycin is one of the most widely used antibiotics, yet its biosynthetic pathway remains unclear. Current proposals suggest that the kanamycin biosynthetic products are linearly related via single enzymatic transformations. To explore this system, we have reconstructed the entire biosynthetic pathway through the heterologous expression of combinations of putative biosynthetic genes from Streptomyces kanamyceticus in the non-aminoglycoside-producing Streptomyces venezuelae. Unexpectedly, we discovered that the biosynthetic pathway contains an early branch point, governed by the substrate promiscuity of a glycosyltransferase, that leads to the formation of two parallel pathways in which early intermediates are further modified. Glycosyltransferase exchange can alter flux through these two parallel pathways, and the addition of other biosynthetic enzymes can be used to synthesize known and new highly active antibiotics. These results complete our understanding of kanamycin biosynthesis and demonstrate the potential of pathway engineering for direct in vivo production of clinically useful antibiotics and more robust aminoglycosides.
authors: Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, Republic of Korea.
authors: Je Won
authors: JW
authors: Park
authors: Sung Ryeol
authors: SR
authors: Park
authors: Keshav Kumar
authors: KK
authors: Nepal
authors: Ah Reum
authors: AR
authors: Han
authors: Yeon Hee
authors: YH
authors: Ban
authors: Young Ji
authors: YJ
authors: Yoo
authors: Eun Ji
authors: EJ
authors: Kim
authors: Eui Min
authors: EM
authors: Kim
authors: Dooil
authors: D
authors: Kim
authors: Jae Kyung
authors: JK
authors: Sohng
authors: Yeo Joon
authors: YJ
authors: Yoon
mesh_terms: D002474:Cell-Free System; D004926:Escherichia coli / Q000187:drug effects; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D005818:Genetic Engineering; D007612:Kanamycin / Q000031:analogs & derivatives* / Q000096:biosynthesis* / Q000737:chemistry; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D015394:Molecular Structure; D009154:Mutation; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013302:Streptomyces / Q000235:genetics / Q000378:metabolism*
chemical_list: D007612:Kanamycin