Ugp and PitA Participate in the Selection of PHO-Constitutive Mutants

Autor(es)

Neves, Henrique Iglesias ^[1] ; Pereira, Tuanny Fernanda ^[1] ; Yagil, Ezra ^[2] ; Spira, Beny ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Ciencias Biomed, Dept Microbiol, BR-05508 Sao Paulo, SP - Brazil

^[2] Tel Aviv Univ, Dept Biochem & Mol Biol, IL-69978 Tel Aviv - Israel

• Tipo de documento: Artigo Científico
• Fonte: Journal of Bacteriology; v. 197, n. 8, p. 1378-1385, APR 2015.
• Citações Web of Science: 3

Resumo

Mutations that cause the constitutive expression of the PHO regulon of Escherichia coli occur either in the pst operon or in the phoR gene, which encode, respectively, a high-affinity P-i transport system and a histidine kinase sensor protein. These mutations are normally selected on glycerol-2-phosphate (G2P) as the carbon source in the presence of excess Pi. The emergence of early PHO-constitutive mutants, which appear after growth for up to 48 h on selective medium, depends on the presence of phoA, which codes for a periplasmic alkaline phosphatase, while late mutants, which appear after 48 h, depend both on phoA and on the ugp operon, which encodes a glycerophosphodiester transport system. The emergence of the late mutants hints at an adaptive mutation process. PHO-constitutive phoR mutants appear only in a host that is mutated in pitA, which encodes an alternative Pi transport system that does not belong to the PHO regulon. The conserved Thr(217) residue in the PhoR protein is essential for PHO repression. (AU)

• Processo FAPESP: 13/19307-9 - Mutações adaptativas no operon pst de Escherichia coli
• Beneficiário: Beny Spira
• Modalidade de apoio: Auxílio à Pesquisa - Regular