Regulation of Tyrosine and Phenylalanine Biosynthesis in Escherichia coli K-12: Properties of the tyrR Gene Product
AUTOR(ES)
Camakaris, H.
RESUMO
A spontaneous amber tyrR mutant has been isolated in which constitutive synthesis of 3-deoxy-d-arabinoheptulosonic acid 7-phosphate (DAHP) synthetase (tyr) and DAHP synthetase (phe) is suppressible by supC−, supD−, supF− and supU−. This finding suggests the tyrR gene product is a protein. Derepression of DAHP synthetase (phe) in this and in seven other spontaneous tyrR mutants and in four Mu-1-induced tyrR mutants provides further evidence for the involvement of the tyrR gene product in phenylalanine biosynthesis. Evidence that the tyrR product is a component of repressor, rather than an enzyme involved in its synthesis or modification, comes from a study of a temperature-sensitive tyrR mutant. This mutant is of the thermolabile type, since derepression occurs rapidly and in the presence and absence of growth.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=246363Documentos Relacionados
- Tyrosine and Phenylalanine Biosynthesis in Escherichia coli K-12: Complementation Between Different tyrR Alleles
- Regulation of expression of the Escherichia coli K-12 mtr gene by TyrR protein and Trp repressor.
- Physical map location and transcriptional orientation of the tyrR gene of Escherichia coli K-12.
- Cloning and characterization of Escherichia coli K-12 regulator gene tyrR.
- Regulation of aroL expression by TyrR protein and Trp repressor in Escherichia coli K-12.