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Identification of a tyrosine decarboxylase gene (tdcA) in Streptococcus thermophilus 1TT45 and analysis of its expression and tyramine production in milk.

ABSTRACT: In this study, a tyrosine decarboxylase gene (tdcA) was identified in 1 among 83 Streptococcus thermophilus strains tested. Its sequence, nearly identical to that of a tdcA of Lactobacillus curvatus, indicated a horizontal gene transfer event. Transcription in milk and the formation of critical levels of tyramine were observed in the presence of tyrosine.

SUBMITTER: La Gioia F

PROVIDER: S-EPMC3028712 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Identification of a tyrosine decarboxylase gene (tdcA) in Streptococcus thermophilus 1TT45 and analysis of its expression and tyramine production in milk.

La Gioia Federica F Rizzotti Lucia L Rossi Franca F Gardini Fausto F Tabanelli Giulia G Torriani Sandra S

Applied and environmental microbiology 20101203 3

In this study, a tyrosine decarboxylase gene (tdcA) was identified in 1 among 83 Streptococcus thermophilus strains tested. Its sequence, nearly identical to that of a tdcA of Lactobacillus curvatus, indicated a horizontal gene transfer event. Transcription in milk and the formation of critical levels of tyramine were observed in the presence of tyrosine. ...[more]

PMID: 21131517

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