Bacteria amino acid decarboxylases

Presence of cofactor-dependent inducible amino acid decarboxylases in bacteria established. 5, 6, 7... 

Commercial 0. oeni strains are selected for their oenological parameters, including the absence of amino acid decarboxylases. According to the in vitro studies done by Moreno-Arribas et al. (2003), none of the four commercial malolactic starter cultures tested could produce histamine, tyramine or putrescine. Martln-Alvarez et al. (2006) also compared inoculation with spontaneous malolactic fermentation in 224 samples of Spanish red wine. They found that inoculation with a commercial starter culture of lactic acid bacteria could reduce the incidence of biogenic amines compared to spontaneous malolactic fermentation in wines. Starter cultures could eliminate indigenous bacteria, or could possibly degrade the biogenic amines produced by the undesirable strains. 

Amino acid decarboxylases are the enzymes responsible for the synthesis of biogenic amines. These proteins and the genes that encode them have been studied in several lactic acid bacteria in wine and are briefly discussed below. 

Specific L-amino acid decarboxylases, produced by certain bacteria under selected growth conditions, catalyze the decarboxylation of certain amino acids (Ref. 54, Equation 16). 

Tyrosine can be decarboxylated to tyramine by aromatic L-amino acid decarboxylase of intestinal bacteria. Tyramine, which is present in large amounts in certain foods (e.g., aged cheeses, red wines), is converted by monoamine oxidase (MAO) to the aldehyde derivatives. However, individuals who are receiving MAO inhibitors for the treatment of depression can accumulate high levels of tyramine, causing release of norepinephrine from sympathetic nerve endings and of epinephrine from the adrenal medulla. This results in peripheral vasoconstriction and increased cardiac output, which lead to hypertensive crises that can cause headaches, palpitations, subdural hemorrhage, stroke, or myocardial infarction. 

Bover-Cid, S., Hugas, M., Izquierdo-Pulido, M., Vidal-Carou, M. C. (2000). Amino acid-decarboxylase activity of bacteria isolated from fermented pork sausages. International Journal of Food Microbiology, 66,185-189. ht //dx.doi.org/10.1016/S0168-1605(00)00526-2. 

Nakazawa, H., Kumagai, H., Yamada, H. (1977). Distrihution and formation of aromatic L-amino acid decarboxylase in bacteria. Agricultural and Biological Chemistry, 41, 2241-2247. 

Amino acid decarboxylases are especially common in bacteria their biologic significance there is unclear. The enzymes are usually specific for one amino acid, and more particularly for the n form. 

Table 7.2 Sequence alignment (amino acids) of ornithine decarboxylase (ODC) of selected taxa from plants, animals, fungi and bacteria. Conserved sites are marked by x ...

Tetracycline targets protein synthesis in Plasmodium via a similar mechanism to that seen in bacteria inhibition of chain elongation and peptide bond formation. Eflornithine interferes with the metabolism of the amino acid ornithine in T. brucei gambiense by acting as a suicide substrate for the enzyme ornithine decarboxylase. 

From a biochemical standpoint, bioamines are mainly formed by the decarboxylation of amino acids due to decarboxylase activity. This phenomenon is assisted by pyridoxal phosphate from yeasts and bacteria (Table 5.4 and Figure 5.9). Bioamines therefore originate from fermentation. 

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