Abstract
Studies of the molecular basis of microbial metabolic activities that are important for the changes in food quality are valuable in order to help in understanding the behavior of spoiling bacteria in food.
The growth of a psychrotrophic Serratia proteamaculans strain was monitored in vitro and in artificially inoculated raw beef. Two growth temperatures (25 °C and 4 °C) were tested in vitro, while growth at 15 °C and 4 °C was monitored in beef. During growth, the expression of inducible lysine and ornithine-decarboxylase genes was evaluated by quantitative reverse transcription-PCR (qRT-PCR), while the presence of cadaverine and putrescine was quantified by LC-ESI–MS/MS. The expression of the decarboxylase genes, and the consequent production of cadaverine and putrescine were shown to be influenced by the temperature, as well as by the complexity of the growth medium. Generally, the maximum gene expression and amine production took place during the exponential and early stationary phase, respectively. In addition, lower temperatures caused slower growth and gene downregulation. Higher amounts of cadaverine compared to putrescine were found during growth in beef with the highest concentrations corresponding to microbial loads of ca. 9 CFU/g. The differences found in gene expression evaluated in vitro and in beef suggested that such activities are more reliably investigated in situ in specific food matrices.
| Original language | English |
|---|---|
| Pages (from-to) | 332-338 |
| Number of pages | 7 |
| Journal | International Journal of Food Microbiology |
| Volume | 165 |
| Issue number | 3 |
| Early online date | 3 Jun 2013 |
| DOIs | |
| Publication status | Published - 1 Aug 2013 |
| Externally published | Yes |
Cite this
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Decarboxylase gene expression and cadaverine and putrescine production by Serratia proteamaculans in vitro and in beef. / De Filippis, Francesca; Pennacchia, Carmela; Di Pasqua, Rosangela; Fiore, Alberto; Fogliano, Vincenzo; Villani, Francesco; Ercolini, Danilo.
In: International Journal of Food Microbiology, Vol. 165, No. 3, 01.08.2013, p. 332-338.Research output: Contribution to journal › Article
TY - JOUR
T1 - Decarboxylase gene expression and cadaverine and putrescine production by Serratia proteamaculans in vitro and in beef
AU - De Filippis, Francesca
AU - Pennacchia, Carmela
AU - Di Pasqua, Rosangela
AU - Fiore, Alberto
AU - Fogliano, Vincenzo
AU - Villani, Francesco
AU - Ercolini, Danilo
PY - 2013/8/1
Y1 - 2013/8/1
N2 - Studies of the molecular basis of microbial metabolic activities that are important for the changes in food quality are valuable in order to help in understanding the behavior of spoiling bacteria in food.The growth of a psychrotrophic Serratia proteamaculans strain was monitored in vitro and in artificially inoculated raw beef. Two growth temperatures (25 °C and 4 °C) were tested in vitro, while growth at 15 °C and 4 °C was monitored in beef. During growth, the expression of inducible lysine and ornithine-decarboxylase genes was evaluated by quantitative reverse transcription-PCR (qRT-PCR), while the presence of cadaverine and putrescine was quantified by LC-ESI–MS/MS. The expression of the decarboxylase genes, and the consequent production of cadaverine and putrescine were shown to be influenced by the temperature, as well as by the complexity of the growth medium. Generally, the maximum gene expression and amine production took place during the exponential and early stationary phase, respectively. In addition, lower temperatures caused slower growth and gene downregulation. Higher amounts of cadaverine compared to putrescine were found during growth in beef with the highest concentrations corresponding to microbial loads of ca. 9 CFU/g. The differences found in gene expression evaluated in vitro and in beef suggested that such activities are more reliably investigated in situ in specific food matrices.
AB - Studies of the molecular basis of microbial metabolic activities that are important for the changes in food quality are valuable in order to help in understanding the behavior of spoiling bacteria in food.The growth of a psychrotrophic Serratia proteamaculans strain was monitored in vitro and in artificially inoculated raw beef. Two growth temperatures (25 °C and 4 °C) were tested in vitro, while growth at 15 °C and 4 °C was monitored in beef. During growth, the expression of inducible lysine and ornithine-decarboxylase genes was evaluated by quantitative reverse transcription-PCR (qRT-PCR), while the presence of cadaverine and putrescine was quantified by LC-ESI–MS/MS. The expression of the decarboxylase genes, and the consequent production of cadaverine and putrescine were shown to be influenced by the temperature, as well as by the complexity of the growth medium. Generally, the maximum gene expression and amine production took place during the exponential and early stationary phase, respectively. In addition, lower temperatures caused slower growth and gene downregulation. Higher amounts of cadaverine compared to putrescine were found during growth in beef with the highest concentrations corresponding to microbial loads of ca. 9 CFU/g. The differences found in gene expression evaluated in vitro and in beef suggested that such activities are more reliably investigated in situ in specific food matrices.
U2 - 10.1016/j.ijfoodmicro.2013.05.021
DO - 10.1016/j.ijfoodmicro.2013.05.021
M3 - Article
VL - 165
SP - 332
EP - 338
JO - International Journal of Food Microbiology
JF - International Journal of Food Microbiology
SN - 0168-1605
IS - 3
ER -