An essential role for actA in acid tolerance of Rhizobium meliloti.
Microbiology (Reading)
; 142 ( Pt 3): 601-610, 1996 Mar.
Article
em En
| MEDLINE
| ID: mdl-8868435
ABSTRACT
The actA gene, which is disrupted by Tn5 in the acid-sensitive mutant of Rhizobium meliloti TG2-6, was cloned and sequenced. It encodes a protein of 541 amino acids with a calculated molecular mass of 57,963 Da and an estimated pl of 9.0. The ActA protein sequence has 30% identity, and much higher similarity (69%), with the CutE protein of Escherichia coli. Like the cutE mutant of E. coli, TG2-6 is sensitive to copper. The reconstructed wild-type actA gene complemented the low pH- and copper-sensitive phenotype of TG2-6. Studies with an actA-lacZ gene fusion showed that actA is constitutively expressed at pH 5.8 and 7.0. The actA gene appears to be chromosomal and is present in all seven strains of R. meliloti tested.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Membrana Transportadoras
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Acetiltransferases
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Proteínas de Bactérias
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Sinorhizobium meliloti
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Proteínas de Escherichia coli
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Proteínas de Membrana
Idioma:
En
Ano de publicação:
1996
Tipo de documento:
Article