Wine Chemistry and Biochemistry

174 M.V. Moreno-Arribas and M.C. Polo

Moreno-Arribas and Lonvaud-Funel (1999). Moreno-Arribas et al. (2000) isolated

and identified a number of tyramine-producing lactic acid bacteria in wine that had

undergone malolactic fermentation; all belonging to thelactobacilli. Tyrosine decar-

boxylase was then purified (Moreno-Arribas and Lonvaud-Funel 2001) and the cor-

responding gene was purified and sequenced (Lucas and Lonvaud-Funel 2002;

Lucas et al. 2003). As far as the literature suggests, no tyramine-producingO. oeni

strain has yet been reported, with the exception of one strain (O. oeniDSM 2025)

that was shown to be able to produce tyramine in a laboratory medium (Choudhury

et al. 1990).

Ornithine decarboxylase (EC.4.1.1.17) is the enzyme that decarboxylates

ornithine to produce putrescine. Marcobal et al. (2004) isolated anO. oeniputrescine-

producing strain from fermentation lees of a Spanish red wine which showed a

high concentration of putrescine. This led to the first report of the presence of

the ornithine decarboxylase gene in the genome ofO. oeniand detectable by PCR

(Marcobal et al. 2004, 2005a). Later, the nucleotide sequence of a 17.2-kb chromo-

somal DNA fragment containing the ornithine decarboxylase gene was determined

(Marcobal et al. 2006b). This DNA fragment contains 13 open reading frames,

including genes coding for 5 transposases and 2 phage proteins. This could per-

haps represent the first evidence of a horizontal gene transfer event as the origin

of a biogenic amine biosynthetic locus. The structure of this gene is presented in

Fig. 6A.3.

.

orf1 orf2

IS 1165

orf3 orf4 orf6

IS 1165 odc potE IS 1165

orf5

ISLpl4

orf 7

...

pAM4

pAM8

pAM11

0 5 10 15

EESn SSSn S S SpS p

kb

Fig. 6A.3Genetic organization of theO. oeniRM83 17.2-kb DNA region containing theodcgene.
Thick and thin arrowsrepresent complete or interrupted ORFs, respectively. The localization of
putative promoters (vertical bent arrow) and predicted transcriptional terminator regions (balland
stick) are indicated. Some of the plasmids used in this study are indicated, as are relevant restriction
sites:E,EcoRV;S, Sau3AI;Sp,SpeI;Sn, SnaBI. Only some of the corresponding restriction sites
present in this fragment are represented (from Marcobal et al. 2006b, with permission)