Characterization of two mutant metJ proteins with reduced, temperature-dependent capacity to regulate Escherichia coli K-12 met regulon elements.
AUTOR(ES)
Bala, G A
RESUMO
At 28 degrees C, but not at 34 or 42 degrees C, strains with the metJ193 allele repressed chromosomal met genes but not a plasmid-borne met promoter. Increasing the metJ193 gene dosage to two copies resulted in overrepression of chromosomal and plasmid-borne met promoters at 28 degrees C. Suppressing the metJ185 amber mutation with supF (tRNATyr) produced the MetJ185F protein. Strains producing MetJ185F repressed chromosomal met promoters but not a plasmid-borne met promoter at 42 degrees C. These are the first known defective MetJ proteins with documented temperature-dependent function.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=210172Documentos Relacionados
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