title: Osmolarity modulates the expression of the Hha protein from Escherichia coli.
abstract: The effect of the osmolarity of the culture medium on the expression of the hha gene of Escherichia coli was investigated. When cells were grown in LB medium, expression reached a maximum in the exponential phase of growth and decreased in the stationary phase. Increasing the osmolarity of the LB medium had no significant effect on the expression of the hha gene, but depletion of NaCl led to a significant decrease in expression. Expression of the hha gene is thus sensitive to the osmolarity of the growth medium. High levels of expression of the hha gene when cells are grown at medium to high osmolarity are consistent with the finding that the Hha protein appears to play its main modulatory role when cells grow under these conditions.
authors.affiliation: Departamento de Microbiología, Universidad de Barcelona, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Mouriño
authors.forename: C
authors.initials: C
authors.lastname: Balsalobre
authors.forename: C
authors.initials: C
authors.lastname: Madrid
authors.forename: J M
authors.initials: JM
authors.lastname: Nieto
authors.forename: A
authors.initials: A
authors.lastname: Prenafeta
authors.forename: F J
authors.initials: FJ
authors.lastname: Muñoa
authors.forename: A
authors.initials: A
authors.lastname: Juárez
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics*; D003470:Culture Media; D004268:DNA-Binding Proteins; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D009994:Osmolar Concentration; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C079209:hha protein, E coli; D012965:Sodium Chloride