title: Azotobacter vinelandii mutants that overproduce poly-beta-hydroxybutyrate or alginate.
abstract: Azotobacter vinelandii produces two polymers of industrial importance, i.e. alginate and poly-beta-hydroxybutyrate (PHB). Alginate synthesis constitutes a waste of substrate when seeking to optimize PHB production and, conversely, synthesis of PHB is undesirable when optimizing alginate production. In this study we evaluated the effect of a mutation in algA, the gene encoding the enzyme that catalyzes the first step of the alginate biosynthetic pathway in the production of PHB. We also evaluated production of alginate in strain AT6 carrying a phbB mutation that impairs PHB synthesis. The algA mutation prevented alginate production and increased PHB accumulation up to 5-fold, determined in milligrams per milligram of protein. Similarly, the phbB mutation increased alginate production up to 4-fold.
authors.affiliation: Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apartado Postal 510-3, 62250 Cuernavaca, Morelos, México.
authors.forename: D
authors.initials: D
authors.lastname: Segura
authors.forename: J
authors.initials: J
authors.lastname: Guzmán
authors.forename: G
authors.initials: G
authors.lastname: Espín
mesh_terms: D000217:Acyltransferases / Q000235:genetics; D000464:Alginates / Q000378:metabolism*; D016948:Azotobacter vinelandii / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D001426:Bacterial Proteins; D003470:Culture Media; D020723:Glucuronic Acid / Q000378:metabolism*; D006603:Hexuronic Acids / Q000378:metabolism*; D006885:Hydroxybutyrates / Q000378:metabolism*; D008359:Mannose-6-Phosphate Isomerase / Q000235:genetics; D009097:Multienzyme Complexes / Q000235:genetics; D009154:Mutation; D009713:Nucleotidyltransferases / Q000235:genetics; D011091:Polyesters / Q000378:metabolism*; D000094122:Polyhydroxybutyrates
chemical_list: D000217:Acyltransferases; D000464:Alginates; D001426:Bacterial Proteins; D003470:Culture Media; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D006885:Hydroxybutyrates; D008359:Mannose-6-Phosphate Isomerase; D009097:Multienzyme Complexes; D009713:Nucleotidyltransferases; D011091:Polyesters; C080207:phosphomannose isomerase-guanosine diphospho-D-mannose pyrophosphorylase; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates; C060970:poly-beta-hydroxybutyrate polymerase