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Isotopic resonance hypothesis: experimental verification by Escherichia coli growth measurements.

Xie X, Zubarev RA - Sci Rep (2015)

Bottom Line: To test the predictions of this hypothesis for the elements C, H, N and O, we designed a precise (standard error ±0.05%) experiment that measures the parameters of bacterial growth in minimal media with varying isotopic composition.The combined statistics extremely strongly supports the validity of the isotopic resonance phenomenon (p ≪ 10(-15)).This phenomenon has numerous implications for the origin of life studies and astrobiology, and possible applications in agriculture, biotechnology, medicine, chemistry and other areas.

View Article: PubMed Central - PubMed

Affiliation: Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17 177 Stockholm, Sweden.

ABSTRACT
Isotopic composition of reactants affects the rates of chemical and biochemical reactions. As a rule, enrichment of heavy stable isotopes leads to progressively slower reactions. But the recent isotopic resonance hypothesis suggests that the dependence of the reaction rate upon the enrichment degree is not monotonous. Instead, at some "resonance" isotopic compositions, the kinetics increases, while at "off-resonance" compositions the same reactions progress slower. To test the predictions of this hypothesis for the elements C, H, N and O, we designed a precise (standard error ±0.05%) experiment that measures the parameters of bacterial growth in minimal media with varying isotopic composition. A number of predicted resonance conditions were tested, with significant enhancements in kinetics discovered at these conditions. The combined statistics extremely strongly supports the validity of the isotopic resonance phenomenon (p ≪ 10(-15)). This phenomenon has numerous implications for the origin of life studies and astrobiology, and possible applications in agriculture, biotechnology, medicine, chemistry and other areas.

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(a) Resonance in lag time at 6.6% 18O. (b) Resonance at the “super-resonance”: at 13C ≈ 9.5%, 15N ≈ 10.9% and 18O ≈ 6.6%. (c) Relative magnitudes of the effects of individual and combined isotope enrichment: blue columns – experimental results; orange columns – extrapolated data.
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f5: (a) Resonance in lag time at 6.6% 18O. (b) Resonance at the “super-resonance”: at 13C ≈ 9.5%, 15N ≈ 10.9% and 18O ≈ 6.6%. (c) Relative magnitudes of the effects of individual and combined isotope enrichment: blue columns – experimental results; orange columns – extrapolated data.

Mentions: As a first step, we tested the resonance at 18O ≈ 6.6% that is valid for molecules containing H and O, i.e. water. The presence of a strong positive effect on growth is obvious in the lag phase domain (ca. −1.3%, p < 0.0002; Figure 5a). At the same time, both maximum growth rate and maximum density increase monotonously with 18O content at least to 10% 18O (Figures S2a and b). This was somewhat unexpected, given that high 18O enrichment is known to be detrimental for bacterial growth10. It is likely that, at even higher 18O content, both maximum growth rate and maximum density will decrease. Such experiments were not performed at this time because of the high cost of 18O-enriched water.


Isotopic resonance hypothesis: experimental verification by Escherichia coli growth measurements.

Xie X, Zubarev RA - Sci Rep (2015)

(a) Resonance in lag time at 6.6% 18O. (b) Resonance at the “super-resonance”: at 13C ≈ 9.5%, 15N ≈ 10.9% and 18O ≈ 6.6%. (c) Relative magnitudes of the effects of individual and combined isotope enrichment: blue columns – experimental results; orange columns – extrapolated data.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4363831&req=5

f5: (a) Resonance in lag time at 6.6% 18O. (b) Resonance at the “super-resonance”: at 13C ≈ 9.5%, 15N ≈ 10.9% and 18O ≈ 6.6%. (c) Relative magnitudes of the effects of individual and combined isotope enrichment: blue columns – experimental results; orange columns – extrapolated data.
Mentions: As a first step, we tested the resonance at 18O ≈ 6.6% that is valid for molecules containing H and O, i.e. water. The presence of a strong positive effect on growth is obvious in the lag phase domain (ca. −1.3%, p < 0.0002; Figure 5a). At the same time, both maximum growth rate and maximum density increase monotonously with 18O content at least to 10% 18O (Figures S2a and b). This was somewhat unexpected, given that high 18O enrichment is known to be detrimental for bacterial growth10. It is likely that, at even higher 18O content, both maximum growth rate and maximum density will decrease. Such experiments were not performed at this time because of the high cost of 18O-enriched water.

Bottom Line: To test the predictions of this hypothesis for the elements C, H, N and O, we designed a precise (standard error ±0.05%) experiment that measures the parameters of bacterial growth in minimal media with varying isotopic composition.The combined statistics extremely strongly supports the validity of the isotopic resonance phenomenon (p ≪ 10(-15)).This phenomenon has numerous implications for the origin of life studies and astrobiology, and possible applications in agriculture, biotechnology, medicine, chemistry and other areas.

View Article: PubMed Central - PubMed

Affiliation: Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17 177 Stockholm, Sweden.

ABSTRACT
Isotopic composition of reactants affects the rates of chemical and biochemical reactions. As a rule, enrichment of heavy stable isotopes leads to progressively slower reactions. But the recent isotopic resonance hypothesis suggests that the dependence of the reaction rate upon the enrichment degree is not monotonous. Instead, at some "resonance" isotopic compositions, the kinetics increases, while at "off-resonance" compositions the same reactions progress slower. To test the predictions of this hypothesis for the elements C, H, N and O, we designed a precise (standard error ±0.05%) experiment that measures the parameters of bacterial growth in minimal media with varying isotopic composition. A number of predicted resonance conditions were tested, with significant enhancements in kinetics discovered at these conditions. The combined statistics extremely strongly supports the validity of the isotopic resonance phenomenon (p ≪ 10(-15)). This phenomenon has numerous implications for the origin of life studies and astrobiology, and possible applications in agriculture, biotechnology, medicine, chemistry and other areas.

Show MeSH
Related in: MedlinePlus