title: Investigating the Physiological and Metabolic Requirements of the Tramway Ridge Microbial Community, Mt Erebus, Antarctica

authors: Vickers, Chelsea Joy

subjects: Microbiology

abstract: Mount Erebus is the most active volcano on the Antarctic continent, and has the most geographically and physically isolated geothermal soil on Earth. It is exposed to some of the most extreme environmental conditions on the planet. Recent preliminary genetic analysis of the microbial community present in the 65°C subsurface soil of Tramway Ridge, Mount Erebus has revealed a unique thermophilic microbial system, with the dominant members possessing little genetic similarity to any known bacteria. The aim of this project was to apply a range of techniques to investigate metabolic and physiological requirements of this poorly understood microbial system. The study included physical-chemical soil surveying, strategic cultivation, community based phenotypic arrays, nutritional enrichment experiments and pyrosequencing. This multifaceted, metabolism driven, approach incorporated both culture dependent and culture independent techniques in order to investigate the intriguing system in a way that is crucial to the understanding of this thermophilic community and the controlling environment. Overall, the results of this study have led to the hypothesis that the Tramway Ridge microbial community is driven by chemolithoautotrophic microorganisms. This hypothesis is supported by a number of observations, firstly that in the absence of carbonate in enrichments, the community shifts to being dominated by obligate heterotrophs; the microbial ecosystem exists in subsurface soils which have limited, or no, light availability; the system is nutrient poor in nature, coupled to a carbon dioxide dominated gas supply from volcanic activity; two of the keystone members identified from pyrosequencing, phylogenetically group with bacterial phyla known for chemolithoautotrophic metabolism. Considering the detailed investigation of this apparently archaic and isolated microbial system, there is potential for this study to become an excellent model for future studies addressing the fundamental functioning and evolutionary processes associated with other thermophilic communities.

text: Investigating the Physiological and Metabolic Requirements of the Tramway Ridge Microbial Community, Mt Erebus, Antarctica Mount Erebus is the most active volcano on the Antarctic continent, and has the most geographically and physically isolated geothermal soil on Earth. It is exposed to some of the most extreme environmental conditions on the planet. Recent preliminary genetic analysis of the microbial community present in the 65°C subsurface soil of Tramway Ridge, Mount Erebus has revealed a unique thermophilic microbial system, with the dominant members possessing little genetic similarity to any known bacteria. The aim of this project was to apply a range of techniques to investigate metabolic and physiological requirements of this poorly understood microbial system. The study included physical-chemical soil surveying, strategic cultivation, community based phenotypic arrays, nutritional enrichment experiments and pyrosequencing. This multifaceted, metabolism driven, approach incorporated both culture dependent and culture independent techniques in order to investigate the intriguing system in a way that is crucial to the understanding of this thermophilic community and the controlling environment. Overall, the results of this study have led to the hypothesis that the Tramway Ridge microbial community is driven by chemolithoautotrophic microorganisms. This hypothesis is supported by a number of observations, firstly that in the absence of carbonate in enrichments, the community shifts to being dominated by obligate heterotrophs; the microbial ecosystem exists in subsurface soils which have limited, or no, light availability; the system is nutrient poor in nature, coupled to a carbon dioxide dominated gas supply from volcanic activity; two of the keystone members identified from pyrosequencing, phylogenetically group with bacterial phyla known for chemolithoautotrophic metabolism. Considering the detailed investigation of this apparently archaic and isolated microbial system, there is potential for this study to become an excellent model for future studies addressing the fundamental functioning and evolutionary processes associated with other thermophilic communities.

year: 2012

title: DZIAH to dance

authors: Cheesman, Sue

subjects: dance

abstract: Sue Cheesman talks to Billy Paea, director of DZIAH, a South Auckland-based hip hop dance crew.

text: DZIAH to dance Sue Cheesman talks to Billy Paea, director of DZIAH, a South Auckland-based hip hop dance crew.

year: 2006

title: Telomere length in early childhood is associated with sex and ethnicity

authors: Ly, Kien

subjects: Science & Technology

abstract: Telomeres are repetitive DNA sequences at the end of chromosomes that function to protect chromosomes from degradation. Throughout the life course, telomere length decreases with age and is influenced by environmental factors and health conditions. This study aimed to determine the relative telomere lengths in a diverse cohort of about 4000 four-year-old children in New Zealand. Linear regression was used to investigate the relationship between telomere length, child gender, ethnicity, paternal age and deprivation. We observed substantial variation in telomere length according to sex and self-identified ethnicity. Telomere length was longer in females compared to males (coefficient of 0.042, 95% confidence interval (CI) 0.024–0.060). European children had shorter telomere than both the indigenous Māori (coefficient of 0.03, CI 0.007–0.055) and Pacific children (coefficient of 0.15, CI 0.12–0.18). The data suggest that telomere lengths are highly variable and variability between individuals arise from early age, influenced partly by sex and ethnicity. Longer telomeres in indigenous Māori and Pacific children may reflect the heritability of telomere length in genetically less complex populations. This study increases our understanding of telomere dynamics in young children since the majority of telomere studies are conducted in adults.

text: Telomere length in early childhood is associated with sex and ethnicity Telomeres are repetitive DNA sequences at the end of chromosomes that function to protect chromosomes from degradation. Throughout the life course, telomere length decreases with age and is influenced by environmental factors and health conditions. This study aimed to determine the relative telomere lengths in a diverse cohort of about 4000 four-year-old children in New Zealand. Linear regression was used to investigate the relationship between telomere length, child gender, ethnicity, paternal age and deprivation. We observed substantial variation in telomere length according to sex and self-identified ethnicity. Telomere length was longer in females compared to males (coefficient of 0.042, 95% confidence interval (CI) 0.024–0.060). European children had shorter telomere than both the indigenous Māori (coefficient of 0.03, CI 0.007–0.055) and Pacific children (coefficient of 0.15, CI 0.12–0.18). The data suggest that telomere lengths are highly variable and variability between individuals arise from early age, influenced partly by sex and ethnicity. Longer telomeres in indigenous Māori and Pacific children may reflect the heritability of telomere length in genetically less complex populations. This study increases our understanding of telomere dynamics in young children since the majority of telomere studies are conducted in adults.

year: 2019