Construction and characterization of an NaCl-sensitive mutant of Halomonas elongata impaired in ectoine biosynthesis.
FEMS Microbiol Lett
; 161(2): 293-300, 1998 Apr 15.
Article
em En
| MEDLINE
| ID: mdl-9570121
ABSTRACT
Using transposon mutagenesis we generated a salt-sensitive mutant of the halophilic eubacterium Halomonas elongata impaired in the biosynthesis of the compatible solute ectoine. HPLC determinations of the cytoplasmic solute content showed the accumulation of a biosynthetic precursor of ectoine, L-2,4-diaminobutyric acid. Ectoine and hydroxyectoine were not detectable. This mutant failed to grow in minimal medium with NaCl concentrations exceeding 4%. However, when supplemented with organic osmolytes, the ability to grow in high-salinity medium (15% and higher) was regained. We cloned and sequenced the regions flanking the transposon insertion in the H. elongata chromosome. Sequence comparisons with known proteins revealed significant similarity of the mutated gene to the L-2,4-diaminobutyric acid acetyltransferase from the ectoine biosynthetic pathway in Marinococcus halophilus. Analysis of a PCR product demonstrated that the ectoine biosynthetic genes (ectABC) follow the same order as in M. halophilus.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bacilos e Cocos Aeróbios Gram-Negativos
/
Diamino Aminoácidos
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Revista:
FEMS Microbiol Lett
Ano de publicação:
1998
Tipo de documento:
Article