An improved screening plate method for the detection of amino acid decarboxylase-positive microorganisms (especially lactic acid bacteria) was developed. The suitability and detection level of the designed medium were quantitatively evaluated by confirmation of amine-forming capacity using an HPLC procedure. The potential to produce the biogenic amines (BA) tyramine, histamine, putrescine, and ...

The species Enterococcus faecalis is able to catabolise the amino acid tyrosine into the biogenic amine tyramine by the tyrosine decarboxilase (TDC) pathway Ladero et al. (2012) [1]. The TDC cluster comprises four genes: tyrS, an aminoacyl-tRNA synthetase-like gene; tdcA, which encodes the tyrosine decarboxylase; tyrP, a tyrosine/tyramine exchanger gene and nhaC-2, which encodes an Na(+)/H(+) a...

Tyrosine decarboxylase initializes salidroside biosynthesis. Metabolic characterization of tyrosine decarboxylase gene from Rhodiola crenulata (RcTYDC) revealed that it played an important role in salidroside biosynthesis. Recombinant 53 kDa RcTYDC converted tyrosine into tyramine. RcTYDC gene expression was induced coordinately with the expression of RcUDPGT (the last gene involved in salidros...

Resveratrol has been reported to inhibit monoamine oxidases (MAO). Many substrates or inhibitors of neuronal MAO interact also with other amine oxidases (AO) in peripheral organs, such as semicarbazide-sensitive AO (SSAO), known as primary amine oxidase, absent in neurones, but abundant in adipocytes. We asked whether phenolic compounds (resveratrol, pterostilbene, quercetin, and caffeic acid) ...

The effects of beta-1,3-oligosaccharide elicitor on the metabolism of phenylpropanoids in potato tuber were analyzed quantitatively, by monitoring the time-dependent changes in the levels of seven compounds. The elicitor treatment caused an increase in the pool size of octopamine and tyramine amides (N-p-coumaroyloctopamine, N-feruloyloctopamine, N-p-coumaroyltyramine and N-feruloyltyramine), a...

The characteristic crawling behavior of Drosophila larvae consists of a series of rhythmic waves of peristalsis and episodes of head swinging and turning. The two biogenic amines octopamine and tyramine have recently been shown to modulate various parameters of locomotion, such as muscle contraction, the time spent in pausing or forward locomotion, and the initiation and maintenance of rhythmic...

Since there is an overall augmentation of sympathetic nervous activity in patients with congestive heart failure while adrenal medullary function is normal and neurotransmitter stores are diminished in the heart, investigation was directed to the functional status of adrenergic receptors and available norepinephrine stores in the peripheral vascular beds. Blood flow, determined plethysmographic...

OBJECTIVE Sympathetic vasoconstriction is blunted in contracting human skeletal muscles (functional sympatholysis). In young subjects, infusion of adenosine and ATP increases blood flow, and the latter compound also attenuates α-adrenergic vasoconstriction. In patients with type 2 diabetes and age-matched healthy subjects, we tested 1) the sympatholytic capacity during one-legged exercise, 2) t...

We present a rapid and selective method to increase the volatility of tyrosine and phenylalanine without adding derivative C for high-precision gas chromatography-continuous-flow isotope ratio mass spectrometry (GCC-IRMS) based on enzymatic decarboxylation to yield alkylamines and evaluated for 15N isotopic integrity. Purified tyrosine and phenylalanine were converted to tyramine and phenethyla...

The ability to accumulate tyramine and 2-phenylethylamine by two strains of Enterococcus faecalis and two strains Enterococcus faecium was evaluated in two cultural media added or not with tyrosine. All the enterococcal strains possessed a tyrosine decarboxylase (tyrDC) which determined tyramine accumulation in all the conditions tested, independently on the addition of high concentration of fr...