title: Role of Azotobacter vinelandii mucA and mucC gene products in alginate production.
abstract: Azotobacter vinelandii produces the exopolysaccharide alginate, which is essential for its differentiation to desiccation-resistant cysts. In different bacterial species, the alternative sigma factor sigma(E) regulates the expression of functions related to the extracytoplasmic compartments. In A. vinelandii and Pseudomonas aeruginosa, the sigma(E) factor (AlgU) is essential for alginate production. In both bacteria, the activity of this sigma factor is regulated by the product of the mucA, mucB, mucC, and mucD genes. In this work, we studied the transcriptional regulation of the A. vinelandii algU-mucABCD gene cluster, as well as the role of the mucA and mucC gene products in alginate production. Our results show the existence of AlgU autoregulation and show that both MucA and MucC play a negative role in alginate production.
authors.affiliation: Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62251, Mexico.
authors.forename: C
authors.initials: C
authors.lastname: Núñez
authors.forename: R
authors.initials: R
authors.lastname: León
authors.forename: J
authors.initials: J
authors.lastname: Guzmán
authors.forename: G
authors.initials: G
authors.lastname: Espín
authors.forename: G
authors.initials: G
authors.lastname: Soberón-Chávez
mesh_terms: D000464:Alginates / Q000378:metabolism*; D016948:Azotobacter vinelandii / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D001483:Base Sequence; D002237:Carbohydrate Dehydrogenases / Q000235:genetics; D004269:DNA, Bacterial; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D020723:Glucuronic Acid; D006360:Heat-Shock Proteins / Q000235:genetics; D006603:Hexuronic Acids; D008969:Molecular Sequence Data; D005810:Multigene Family; D016296:Mutagenesis; D012697:Serine Endopeptidases; D012808:Sigma Factor / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic; D015533:Transcriptional Activation
chemical_list: C079619:AlgU protein, Pseudomonas aeruginosa; D000464:Alginates; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D006360:Heat-Shock Proteins; D006603:Hexuronic Acids; C063757:MucA protein, Bacteria; C093590:MucB protein, Bacteria; C097648:MucC protein, Pseudomonas aeruginosa; D012808:Sigma Factor; D014157:Transcription Factors; C069774:heat-shock sigma factor 32; D020723:Glucuronic Acid; D002237:Carbohydrate Dehydrogenases; C020562:GDPmannose dehydrogenase; C097649:MucD protein, Pseudomonas aeruginosa; D012697:Serine Endopeptidases