Introduction: Investigations of Mars as a potential habitat for past or present life depend on un... more Introduction: Investigations of Mars as a potential habitat for past or present life depend on understanding the chemistry of the Martian soil as it affects the preservation of organic compounds and thus the risk of forward contamination as well as the suitability of organic compounds as biomarkers. The classical Gas Exchange Experiment and the Labeled Release Experiment conducted by the Viking Landers demonstrated that the Martian surface soil is oxidizing [1, 2]. However, the cause of the soil’s oxidizing properties is uncertain [3]. The Martian surface material mainly consists of silicates [4] that due to wind erosion has a very fine grained texture. Based on the composition of the surface material and investigations showing that crushing of silicates can give rise to reactive oxygen species [5], we hypothesized that wind erosion of silicates can explain the reactivity of Martian soil. Methods: We simulated wind-erosion of silicates by tumbling quartz sand in sealed quartz ampoul...
Studies of tardigrade biology have been severely limited by the sparsity of appropriate quantitat... more Studies of tardigrade biology have been severely limited by the sparsity of appropriate quantitative techniques, informative on a single-organism level. Therefore, many studies rely on motility-based survival scoring and quantifying reproductive success. Measurements of O2 respiration rates, as an integrating expression of the metabolic activity of single tardigrades, would provide a more comprehensive insight into how an individual tardigrade is responding to specific environmental factors or changes in life stages. Here we present and validate a new method for determining the O2 respiration rate (nmol O2 mg−1 hour−1) of single tardigrades under steady state, using O2-microsensors. As an example, we show that the O2 respiration rate determined in MilliQ water for individuals of Richtersius coronifer and of Macrobiotus macrocalix at 22 °C was 10.8±1.8 nmol O2 mg−1 hour−1 and 13.1±2.3 nmol O2 mg−1 hour−1, respectively.
Introduction: Investigations of Mars as a potential habitat for past or present life depend on un... more Introduction: Investigations of Mars as a potential habitat for past or present life depend on understanding the chemistry of the Martian soil as it affects the preservation of organic compounds and thus the risk of forward contamination as well as the suitability of organic compounds as biomarkers. The classical Gas Exchange Experiment and the Labeled Release Experiment conducted by the Viking Landers demonstrated that the Martian surface soil is oxidizing [1, 2]. However, the cause of the soil’s oxidizing properties is uncertain [3]. The Martian surface material mainly consists of silicates [4] that due to wind erosion has a very fine grained texture. Based on the composition of the surface material and investigations showing that crushing of silicates can give rise to reactive oxygen species [5], we hypothesized that wind erosion of silicates can explain the reactivity of Martian soil. Methods: We simulated wind-erosion of silicates by tumbling quartz sand in sealed quartz ampoul...
Studies of tardigrade biology have been severely limited by the sparsity of appropriate quantitat... more Studies of tardigrade biology have been severely limited by the sparsity of appropriate quantitative techniques, informative on a single-organism level. Therefore, many studies rely on motility-based survival scoring and quantifying reproductive success. Measurements of O2 respiration rates, as an integrating expression of the metabolic activity of single tardigrades, would provide a more comprehensive insight into how an individual tardigrade is responding to specific environmental factors or changes in life stages. Here we present and validate a new method for determining the O2 respiration rate (nmol O2 mg−1 hour−1) of single tardigrades under steady state, using O2-microsensors. As an example, we show that the O2 respiration rate determined in MilliQ water for individuals of Richtersius coronifer and of Macrobiotus macrocalix at 22 °C was 10.8±1.8 nmol O2 mg−1 hour−1 and 13.1±2.3 nmol O2 mg−1 hour−1, respectively.
Uploads
Papers by Kai Finster