Nucleotide sequence of the phoS gene, the structural gene for the phosphate-binding protein of Escherichia coli

Abstract

phoS is the structural gene for the phosphate-binding protein, which is localized in periplasm and involved in active transport of phosphate in Escherichia coli. It is also a negative regulatory gene for the pho regulon, and the gene expression is inducible by phosphate starvation. The complete nucleotide sequence of the phoS gene was determined by the method of Maxam and Gilbert (A. M. Maxam and W. Gilbert, Methods Enzymol. 65:499-560, 1980). The amino acid sequences at the amino termini of the pre-PhoS and PhoS proteins and at the carboxy terminus of the PhoS protein were determined by using the purified proteins. Furthermore, the amino acid sequence of enzymatically digested peptide fragments of the PhoS protein was determined. The combined data established the nucleotide sequence of the coding region and the amino acid sequence of the pre-PhoS and the PhoS proteins. The pre-PhoS protein contains an extension of peptide composed of 25 amino acid residues at the amino terminus of the PhoS protein, which has the general characteristics of a signal peptide. The mature PhoS protein is composed of 321 amino acid residues, with a calculated molecular weight of 34,422, and lacks the disulfide bond and methionine. The regulatory region of phoS contains a characteristic Shine-Dalgarno sequence at an appropriate position preceding the translational initiation site, as well as three possible Pribnow boxes and one-35 sequence. The nucleotide sequence of the regulatory region of phoS was compared with those of phoA and phoE, the genes constituting the pho regulon.

Phosphate-specific transport system of Escherichia coli: nucleotide sequence and gene-polypeptide relationships

“…Four open reading frames were detected beyond the end of the previously described phoS gene (19,33) and within the region specified above. The open reading frames (ORFs) are transcribed in the same direction as the phoS gene (19,33), and each is preceded by a putative ribosome-binding site appropriately spaced (32) from a presumed ATG initiating codon. ORF-1 and ORF-2 have overlapping stop-start codons.…”

“…11) transcribed in a counterclockwise direction and located at about 83 min on the E. coli chromosome (3). The complete nucleotide sequence of the phoS gene, coding for the periplasmic phosphate-binding protein, has been described previously (19,33) and the nucleotide sequence of the remaining four genes and the intergenic sequences are described in the present paper. The translation start sites must be regarded as tentative until confirmatory amino acid sequences of the corresponding proteins have been determined.…”

“…They did not investigate the pstB locus, and they proposed the gene order to be bgl ... phoU (pst-2 phoT) phoS, with the phoS gene having its own promoter. Later Magota et al (19), on the basis of complementation tests with plasmids carrying DNA segments of the phoS-phoU region and fine physical mapping by Tn1000 insertion inactivation, proposed the gene order to be bgl . .. phoU pstB phoT (pstA) phoS, with the phoS gene having its own promoter.…”

“…Asterisks denote the translational stop codon (TAA). The 3' end of the phoS gene(19,33) is shown preceding ORF-1.DNA sequence analysis. DNA sequences were determinedMaterials.…”

Estudo da resposta imunológica de anticorpos IgG, IgM e IgA, subclasses de IgG (IgG1 e IgG3) e avidez de IgG, por Western Blotting, em amostras de soros de pacientes com tuberculose pulmonar e comparação de resultados com métodos microbiológicos e dosagem de interferon-gama

“…A proteína de 38kDa também denominada de antígeno 78, antígeno 5 ou proteína antígeno B (PAB) é uma proteína específica do M tuberculosis e é o imunógeno mais importante desta micobactéria (Kadival et al, 1987;Haslov et al, 1990;Harboe e Wiker, 1992) Clonagem e o sequecinamento do gene que codifica a proteína de 38kDa revelou 30% de identidade seqüencial com o fosfato ligador a proteínas (PBP, também designado Phos ou PSTs) de Escherichia coli (Andersen e Hansen, 1989;Surin et al, 1984;Magota et al, 1984). A proteína de 38kDa é uma lipoproteína (Harboe e Wiker, 1992).…”