Identification of a tyrosine decarboxylase gene (tdcA) in Streptococcus thermophilus 1TT45 and analysis of its expression and tyramine production in milk.
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.
Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada le Grazie 15, 37134 Verona, Italy.
Federica
F
La Gioia
Lucia
L
Rizzotti
Franca
F
Rossi
Fausto
F
Gardini
Giulia
G
Tabanelli
Sandra
S
Torriani
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002611:Cheese / Q000382:microbiology; D003612:Dairying; D008892:Milk / Q000737:chemistry* / Q000378:metabolism; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D048249:Streptococcus thermophilus / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D014439:Tyramine / Q000096:biosynthesis*; D014445:Tyrosine Decarboxylase / Q000235:genetics* / Q000378:metabolism*
D001426:Bacterial Proteins; D014445:Tyrosine Decarboxylase; D014439:Tyramine