|
type |
Journal Article |
authors |
Connil, N.; Le Breton, Y.; Dousset, X.; Auffray, Y.; Rince, A.; Prevost, H. |
title |
Identification of the Enterococcus faecalis tyrosine decarboxylase operon involved in tyramine production |
journal |
Appl Environ Microbiol |
Activity |
4.1.1.25 |
Family |
4.1.1.25.a |
sel |
selected |
ui |
12089039 |
year |
(2002) |
volume |
68 |
number |
7 |
pages |
3537-44 |
| |
keywords |
Amino Acid Sequence |
abstract |
Screening of a library of Enterococcus faecalis insertional mutants allowed isolation of a mutant affected in tyramine production. The growth of this mutant was similar to that of the wild-type E. faecalis JH2-2 strain in Maijala broth, whereas high-performance liquid chromatography analyses showed that tyramine production, which reached 1,000 microg ml(-1) for the wild-type strain, was completely abolished. Genetic analysis of the insertion locus revealed a gene encoding a decarboxylase with similarity to eukaryotic tyrosine decarboxylases. Sequence analysis revealed a pyridoxal phosphate binding site, indicating that this enzyme belongs to the family of amino acid decarboxylases using this cofactor. Reverse transcription-PCR analyses demonstrated that the gene (tdc) encoding the putative tyrosine decarboxylase of E. faecalis JH2-2 is cotranscribed with the downstream gene encoding a putative tyrosine-tyramine antiporter and with the upstream tyrosyl-tRNA synthetase gene. This study is the first description of a tyrosine decarboxylase gene in prokaryotes. |
last changed |
2009/06/12 11:29 |
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