title: Investigation into the microbial ecology and persistence of soil taxa through trace-gas oxidation in Tongariro National Park

authors: Peach, Hanna Annette Caroline Georgia

subjects: Trade Gas Oxidation

abstract: Cultivation-dependent and metagenomic surveys of bare, volcanic and hyperarid oligotrophic ecosystems have revealed surprisingly diverse microbial communities¹⁻⁴. The richness of Mt. Tongariro soil communities is surprising considering the extreme environmental parameters. Given that soil moisture on Mt. Tongariro is highly variable dependent on season, and both phototrophic Cyanobacteria and trace gas oxidising taxa from the phyla Actinobacteria, WPS-2 and AD3 are detected in these soils, it is postulated that these taxa alternate as the primary producers in these oligotrophic soils. In this scenario, cyanobacteria are the phototrophic backbone and trace-gas oxidisers use atmospheric trace gases (H₂, CO) as supplemental cell energy for mixotrophic metabolism to persist. Mt. Tongariro soil communities were shown to encode high affinity hydrogenases and carbon monoxide dehydrogenases, which are necessary for atmospheric oxidation of H₂ and CO. This thesis details the microbial ecology and effect of physicochemistry on the alpha and beta diversity of Mt. Tongariro soils. It also addresses microbial persistence by the use oxidation of trace gases H₂ and CO at 4 °C and 60 °C for the South, Red and Central Craters of Mt. Tongariro on the southernmost point of the Taupo Volcanic Centre (TVZ), and control soils from White Island (Whakaari), Mt. Urchin and Mt. Sugarloaf. This preliminary study uncovers the microbial ecology of Mt. Tongariro and other bare, high elevation control soils from around New Zealand. Although, more extensive testing is required such as testing isolated Mt. Tongariro strains to understand whether the thermophilic taxa present are capable of oxidising trace gas, or whether they harbour low affinity enzymes suited to elevated levels of CO and H₂. This study indicates that trace gas oxidation may be an important mechanism for persistence or a dependable source of supplemental energy to specific mixotrophic trace-gas oxidising taxa in all communities from bare, oligotrophic systems.

text: Investigation into the microbial ecology and persistence of soil taxa through trace-gas oxidation in Tongariro National Park Cultivation-dependent and metagenomic surveys of bare, volcanic and hyperarid oligotrophic ecosystems have revealed surprisingly diverse microbial communities¹⁻⁴. The richness of Mt. Tongariro soil communities is surprising considering the extreme environmental parameters. Given that soil moisture on Mt. Tongariro is highly variable dependent on season, and both phototrophic Cyanobacteria and trace gas oxidising taxa from the phyla Actinobacteria, WPS-2 and AD3 are detected in these soils, it is postulated that these taxa alternate as the primary producers in these oligotrophic soils. In this scenario, cyanobacteria are the phototrophic backbone and trace-gas oxidisers use atmospheric trace gases (H₂, CO) as supplemental cell energy for mixotrophic metabolism to persist. Mt. Tongariro soil communities were shown to encode high affinity hydrogenases and carbon monoxide dehydrogenases, which are necessary for atmospheric oxidation of H₂ and CO. This thesis details the microbial ecology and effect of physicochemistry on the alpha and beta diversity of Mt. Tongariro soils. It also addresses microbial persistence by the use oxidation of trace gases H₂ and CO at 4 °C and 60 °C for the South, Red and Central Craters of Mt. Tongariro on the southernmost point of the Taupo Volcanic Centre (TVZ), and control soils from White Island (Whakaari), Mt. Urchin and Mt. Sugarloaf. This preliminary study uncovers the microbial ecology of Mt. Tongariro and other bare, high elevation control soils from around New Zealand. Although, more extensive testing is required such as testing isolated Mt. Tongariro strains to understand whether the thermophilic taxa present are capable of oxidising trace gas, or whether they harbour low affinity enzymes suited to elevated levels of CO and H₂. This study indicates that trace gas oxidation may be an important mechanism for persistence or a dependable source of supplemental energy to specific mixotrophic trace-gas oxidising taxa in all communities from bare, oligotrophic systems.

year: 2019

title: Determination of total potentially available nucleosides in bovine milk

authors: Gill, Brendon D.

subjects: milk

abstract: Bovine colostrum and milk samples were collected from two herds over the course of the first month post-partum, pooled for each herd by stage of lactation and total potentially available nucleosides were determined. Sample analysis consisted of parallel enzymatic treatments, phenylboronate clean-up, and liquid chromatography to quantify contributions of nucleosides, monomeric nucleotides, nucleotide adducts, and polymeric nucleotides to the available nucleosides pool. Bovine colostrum contained high levels of nucleosides and monomeric nucleotides, which rapidly decreased as lactation progressed into transitional milk. Mature milk was relatively consistent in nucleoside and monomeric nucleotide concentrations from approximately the tenth day post-partum. Differences in concentrations between summer-milk and winter-milk herds were largely attributable to variability in uridine and monomeric nucleotide concentrations.

text: Determination of total potentially available nucleosides in bovine milk Bovine colostrum and milk samples were collected from two herds over the course of the first month post-partum, pooled for each herd by stage of lactation and total potentially available nucleosides were determined. Sample analysis consisted of parallel enzymatic treatments, phenylboronate clean-up, and liquid chromatography to quantify contributions of nucleosides, monomeric nucleotides, nucleotide adducts, and polymeric nucleotides to the available nucleosides pool. Bovine colostrum contained high levels of nucleosides and monomeric nucleotides, which rapidly decreased as lactation progressed into transitional milk. Mature milk was relatively consistent in nucleoside and monomeric nucleotide concentrations from approximately the tenth day post-partum. Differences in concentrations between summer-milk and winter-milk herds were largely attributable to variability in uridine and monomeric nucleotide concentrations.

year: 2010

title: Potential science tools to support mahinga kai decision-making in freshwater management

authors: Collier, Kevin J.

subjects: mahinga kai

abstract: Mahinga kai is a key value for freshwater management that needs to be articulated in objective setting for environmental limits in the National Objectives Framework (NOF). Mahinga kai generally refers to indigenous freshwater species that have traditionally been used for food, tools or other resources. Many mahinga kai sites, both current and historical, are in lowland settings where freshwater environments are often in a degraded state and values are correspondingly compromised. With limited availability of sites in good condition within rohe to help define desired states for mahinga kai, alternative approaches are needed to establish condition bands for management. In particular, tools that assist with envisaging desired states and predicting environmental changes required to sustain those states will help communities and tangata whenua set management objectives. To achieve this effectively an approach is required that utilises Mātauranga Māori and science tools

text: Potential science tools to support mahinga kai decision-making in freshwater management Mahinga kai is a key value for freshwater management that needs to be articulated in objective setting for environmental limits in the National Objectives Framework (NOF). Mahinga kai generally refers to indigenous freshwater species that have traditionally been used for food, tools or other resources. Many mahinga kai sites, both current and historical, are in lowland settings where freshwater environments are often in a degraded state and values are correspondingly compromised. With limited availability of sites in good condition within rohe to help define desired states for mahinga kai, alternative approaches are needed to establish condition bands for management. In particular, tools that assist with envisaging desired states and predicting environmental changes required to sustain those states will help communities and tangata whenua set management objectives. To achieve this effectively an approach is required that utilises Mātauranga Māori and science tools

year: 2014