title: New insights into paulomycin biosynthesis pathway in Streptomyces albus J1074 and generation of novel derivatives by combinatorial biosynthesis.
abstract: BACKGROUND
  Streptomyces albus J1074 produces glycosylated antibiotics paulomycin A, B and E that derive from chorismate and contain an isothiocyanate residue in form of paulic acid. Paulomycins biosynthesis pathway involves two glycosyltransferases, three acyltransferases, enzymes required for paulic acid biosynthesis (in particular an aminotransferase and a sulfotransferase), and enzymes involved in the biosynthesis of two deoxysugar moieties: D-allose and L-paulomycose.
  
  
  RESULTS
  Inactivation of genes encoding enzymes involved in deoxysugar biosynthesis, paulic acid biosynthesis, deoxysugar transfer, and acyl moieties transfer has allowed the identification of several biosynthetic intermediates and shunt products, derived from paulomycin intermediates, and to propose a refined version of the paulomycin biosynthesis pathway. Furthermore, several novel bioactive derivatives of paulomycins carrying modifications in the L-paulomycose moiety have been generated by combinatorial biosynthesis using different plasmids that direct the biosynthesis of alternative deoxyhexoses.
  
  
  CONCLUSIONS
  The paulomycins biosynthesis pathway has been defined by inactivation of genes encoding glycosyltransferases, acyltransferases and enzymes involved in paulic acid and L-paulomycose biosynthesis. These experiments have allowed the assignment of each of these genes to specific paulomycin biosynthesis steps based on characterization of products accumulated by the corresponding mutant strains. In addition, novel derivatives of paulomycin A and B containing L-paulomycose modified moieties were generated by combinatorial biosynthesis. The production of such derivatives shows that L-paulomycosyl glycosyltransferase Plm12 possesses a certain degree of flexibility for the transfer of different deoxysugars. In addition, the pyruvate dehydrogenase system form by Plm8 and Plm9 is also flexible to catalyze the attachment of a two-carbon side chain, derived from pyruvate, into both 2,6-dideoxyhexoses and 2,3,6-trideoxyhexoses. The activity of the novel paulomycin derivatives carrying modifications in the L-paulomycose moiety is lower than the original compounds pointing to some interesting structure-activity relationships.
authors.affiliation: Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, C/Julian Claveria s/n, 33006, Oviedo (Asturias), Spain.
authors.forename: Aránzazu
authors.initials: A
authors.lastname: González
authors.affiliation: Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, C/Julian Claveria s/n, 33006, Oviedo (Asturias), Spain.
authors.forename: Miriam
authors.initials: M
authors.lastname: Rodríguez
authors.affiliation: Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, C/Julian Claveria s/n, 33006, Oviedo (Asturias), Spain.
authors.forename: Alfredo F
authors.initials: AF
authors.lastname: Braña
authors.affiliation: Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, C/Julian Claveria s/n, 33006, Oviedo (Asturias), Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Méndez
authors.affiliation: Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, C/Julian Claveria s/n, 33006, Oviedo (Asturias), Spain.
authors.forename: José A
authors.initials: JA
authors.lastname: Salas
authors.affiliation: Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, C/Julian Claveria s/n, 33006, Oviedo (Asturias), Spain. olanocarlos@uniovi.es.
authors.forename: Carlos
authors.initials: C
authors.lastname: Olano
mesh_terms: D000900:Anti-Bacterial Agents / Q000096:biosynthesis*; D053898:Biosynthetic Pathways / Q000235:genetics; D050260:Carbohydrate Metabolism / Q000235:genetics*; D053138:Cyclohexenes; D003837:Deoxy Sugars / Q000378:metabolism; D004187:Disaccharides / Q000096:biosynthesis; D016695:Glycosyltransferases / Q000235:genetics / Q000378:metabolism; D060847:Metabolic Engineering / Q000379:methods*; D005810:Multigene Family; D030781:Organisms, Genetically Modified; D013302:Streptomyces / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D053138:Cyclohexenes; D003837:Deoxy Sugars; D004187:Disaccharides; C055555:paulomycin E; C034570:paulomycin B; C034569:paulomycin A; D016695:Glycosyltransferases
keywords: Acyl migration; Deoxysugar; Glycosyltranferase; Paulic acid; Paulomenol; Structural analogue