TY - JOUR
T1 - Isotopic composition of inorganic carbon as an indicator of benzoate degradation by Pseudomonas putida: temperature, growth rate and pH effects.
AU - Barth, J.
AU - Hall, J.
AU - Larkin, Mike
AU - Kalin, R.
PY - 2000/7/25
Y1 - 2000/7/25
N2 - Degradation experiments of benzoate by Pseudomonas putida resulted in enzymatic carbon isotope fractionations. However, isotopic temperature effects between experiments at 20 and 30 °C were minor. Averages of the last three values of the CO2 isotopic composition (δ13CCO2(g)) were more negative than the initial benzoate δ13C value (−26.2‰ Vienna Pee Dee Belenite (VPDB)) by 3.8, 3.4 and 3.2‰ at 20, 25 and 30 °C, respectively. Although the maximum isotopic temperature difference found was only 0.6‰, more extreme temperature variations may cause larger isotope effects. In order to understand the isotope effects on the total inorganic carbon (TIC), a better measure is to calculate the proportions of the inorganic carbon species (CO2(g), CO2(aq) and HCO3−) and to determine their cumulative δ13CTIC. In all three experiments δ13CTIC was more positive than the initial isotopic composition of the benzoate at a pH of 7. This suggests an uptake of 12C in the biomass in order to match the carbon balance of these closed system experiments.
AB - Degradation experiments of benzoate by Pseudomonas putida resulted in enzymatic carbon isotope fractionations. However, isotopic temperature effects between experiments at 20 and 30 °C were minor. Averages of the last three values of the CO2 isotopic composition (δ13CCO2(g)) were more negative than the initial benzoate δ13C value (−26.2‰ Vienna Pee Dee Belenite (VPDB)) by 3.8, 3.4 and 3.2‰ at 20, 25 and 30 °C, respectively. Although the maximum isotopic temperature difference found was only 0.6‰, more extreme temperature variations may cause larger isotope effects. In order to understand the isotope effects on the total inorganic carbon (TIC), a better measure is to calculate the proportions of the inorganic carbon species (CO2(g), CO2(aq) and HCO3−) and to determine their cumulative δ13CTIC. In all three experiments δ13CTIC was more positive than the initial isotopic composition of the benzoate at a pH of 7. This suggests an uptake of 12C in the biomass in order to match the carbon balance of these closed system experiments.
UR - http://www.scopus.com/inward/record.url?scp=0033864958&partnerID=8YFLogxK
U2 - 10.1002/1097-0231(20000815)14:15<1316::AID-RCM933>3.0.CO;2-4
DO - 10.1002/1097-0231(20000815)14:15<1316::AID-RCM933>3.0.CO;2-4
M3 - Article
SN - 0951-4198
VL - 14(15)
SP - 1316
EP - 1320
JO - Rapid communications in mass spectrometry
JF - Rapid communications in mass spectrometry
T2 - SIMSUG 2000 Meeting
Y2 - 1 January 2000 through 1 January 2000
ER -