title: The physiological characterisation of a novel Thermomicrobia strain WKT50.2, and a review of the characteristics of the class Thermomicrobia

authors: Houghton, Karen M.

subjects: Thermomicrobia

abstract: Thermomicrobia is a class of heterotrophic, obligate aerobes within the phylum Chloroflexi.  At the time of writing, it contained four distinct species, Thermomicrobium roseum, Sphaerobacter thermophilus, Nitrolancetus hollandicus and WKT50.2, the novel strain described in this study.  The physiology and ecology of this strain, and the description of the class Thermomicrobia was investigated as part of this study.

Strain WKT50.2 was isolated from the hot springs at Waikite, New Zealand. We investigated temperature and pH range and optima, analysed PLFA, and determined preferred carbon and energy sources, N-fixation, modes of growth and antibiotic sensitivity. As a general phenotype, WKT50.2 is a heterotrophic and thermophilic obligate aerobe with a preference for moderately alkaliphilic pH conditions. The possible ecology of WKT50.2 was discussed. 

WKT50.2 was able to oxidise methane to gain energy. This was an unexpected result as methanotrophy is a highly specialised phenotype restricted to the phyla Proteobacteria and Verrucomicrobia. Methanotrophs also tend to be metabolic specialists with no capability to oxidise substrates other than C1 compounds. In contrast, WKT50.2 was also able to oxidise ammonia and nitrite, along with a range of saccharides and protein rich substrates. WKT50.2 was sensitive to most of the antibiotics tested in this study, but metronidazole and trimethoprim both stimulated growth in a dosage-dependent manner. WKT50.2 is clearly a distinct genus from T. roseum and S. thermophilus, based on 16S rRNA gene sequence similarities (91 % and 88 % respectively), G+C content and metabolic capabilities.  

T. roseum and S. thermophilus were confirmed as heterotrophic, thermophilic, moderately alkaliphilic, obligate aerobes.  The temperature and pH optima and ranges for T. roseum and S. thermophilus were amended, along with expanding the known metabolic capabilities of both species. Of particular note was the discovery that both T. roseum and S. thermophilus were also able to oxidise both methane and ammonia for energy, and that both species possessed cellulolytic activity. 

In summary, the class Thermomicrobia can be redefined as comprising obligately aerobic, facultative heterotrophs.  Cells are non-motile, non-spore forming rods.  This study has shown that the cells have proteinaceous cell walls containing ornithine, and no lipopolysaccharide.  The major fatty acid is 12-Me-18:0, and lipids include ester-linked diols. The major isoprenoid quinone is MK-8.

Several of the observations in this study merit further research.  The discovery of methanotrophy in this class was unexpected and significant, and future work should include the identification of the enzymes involved in methanotrophy, and those involved in the oxidation of ammonia for energy. The mechanism for growth stimulation of WKT50.2 and T. roseum by antibiotics was also an interesting observation and warrants further analysis to determine the mode of action.

text: The physiological characterisation of a novel Thermomicrobia strain WKT50.2, and a review of the characteristics of the class Thermomicrobia Thermomicrobia is a class of heterotrophic, obligate aerobes within the phylum Chloroflexi.  At the time of writing, it contained four distinct species, Thermomicrobium roseum, Sphaerobacter thermophilus, Nitrolancetus hollandicus and WKT50.2, the novel strain described in this study.  The physiology and ecology of this strain, and the description of the class Thermomicrobia was investigated as part of this study.

Strain WKT50.2 was isolated from the hot springs at Waikite, New Zealand. We investigated temperature and pH range and optima, analysed PLFA, and determined preferred carbon and energy sources, N-fixation, modes of growth and antibiotic sensitivity. As a general phenotype, WKT50.2 is a heterotrophic and thermophilic obligate aerobe with a preference for moderately alkaliphilic pH conditions. The possible ecology of WKT50.2 was discussed. 

WKT50.2 was able to oxidise methane to gain energy. This was an unexpected result as methanotrophy is a highly specialised phenotype restricted to the phyla Proteobacteria and Verrucomicrobia. Methanotrophs also tend to be metabolic specialists with no capability to oxidise substrates other than C1 compounds. In contrast, WKT50.2 was also able to oxidise ammonia and nitrite, along with a range of saccharides and protein rich substrates. WKT50.2 was sensitive to most of the antibiotics tested in this study, but metronidazole and trimethoprim both stimulated growth in a dosage-dependent manner. WKT50.2 is clearly a distinct genus from T. roseum and S. thermophilus, based on 16S rRNA gene sequence similarities (91 % and 88 % respectively), G+C content and metabolic capabilities.  

T. roseum and S. thermophilus were confirmed as heterotrophic, thermophilic, moderately alkaliphilic, obligate aerobes.  The temperature and pH optima and ranges for T. roseum and S. thermophilus were amended, along with expanding the known metabolic capabilities of both species. Of particular note was the discovery that both T. roseum and S. thermophilus were also able to oxidise both methane and ammonia for energy, and that both species possessed cellulolytic activity. 

In summary, the class Thermomicrobia can be redefined as comprising obligately aerobic, facultative heterotrophs.  Cells are non-motile, non-spore forming rods.  This study has shown that the cells have proteinaceous cell walls containing ornithine, and no lipopolysaccharide.  The major fatty acid is 12-Me-18:0, and lipids include ester-linked diols. The major isoprenoid quinone is MK-8.

Several of the observations in this study merit further research.  The discovery of methanotrophy in this class was unexpected and significant, and future work should include the identification of the enzymes involved in methanotrophy, and those involved in the oxidation of ammonia for energy. The mechanism for growth stimulation of WKT50.2 and T. roseum by antibiotics was also an interesting observation and warrants further analysis to determine the mode of action.

year: 2013

title: Denial and Distancing in Discourses of Development: shadow of the ‘Third World’ in New Zealand

authors: Kurian, Priya A.

subjects: New Zealand

abstract: Anxieties about development in New Zealand show up in a deep-rooted fear of the ‘Third World’ in the country. We examine how the term ‘Third World’ is deployed in media discourses in economic, social and environmental contexts and how this deployment results in a ‘discursive distancing’ from anything associated with the ‘Third World’. Such distancing demonstrates a fragile national identity that struggles with the contradictions between the nation's desire to be part of the ‘First World’ of global capitalism and the growing disparities in health and wealth within it. The shadow of the ‘Third World’ prevents New Zealand from confronting the realities of its own inequities, which in turn comes in the way of a sound development agenda.

text: Denial and Distancing in Discourses of Development: shadow of the ‘Third World’ in New Zealand Anxieties about development in New Zealand show up in a deep-rooted fear of the ‘Third World’ in the country. We examine how the term ‘Third World’ is deployed in media discourses in economic, social and environmental contexts and how this deployment results in a ‘discursive distancing’ from anything associated with the ‘Third World’. Such distancing demonstrates a fragile national identity that struggles with the contradictions between the nation's desire to be part of the ‘First World’ of global capitalism and the growing disparities in health and wealth within it. The shadow of the ‘Third World’ prevents New Zealand from confronting the realities of its own inequities, which in turn comes in the way of a sound development agenda.

year: 2012

title: Te Toi Poto, Te Toi Roa A Critical Evaluation of Māori-State Inclusion in the Ohiwa Harbour Strategy, Aotearoa New Zealand.

authors: Lowry, Amanda

subjects: Māori

abstract: In New Zealand, the State Owned Enterprises Act 1988 [SOE], Local Government Act 2002 [LGA], the Resource Management Act 1991 [RMA] require that government include the voices of Māori, and ensure their contribution to the decision-making processes of local authorities. Accordingly, central and local government have embraced the idea of inclusive partnership as part of policymaking processes informed by shared values both of government and iwi.
Thus, it is not uncommon to see consultations, partnerships and engagement between Māori-state on a range of issues in line with Tikanga and protocols of Māori culture. These transitions reflect contemporary critical policy scholarship that underscores the need to include marginalised voices policymaking, specifically through processes that reflect diverse values. Termed here as ‘procedural inclusion’, these efforts are framed within the wider goal of participatory democracy as part of the efforts to realise an inclusive society. The present research is a critical evaluation of the inclusion of Māori in the processes of policymaking, especially when those processes have been especially designed to be culturally sensitive.
This core objective is developed through the analysis of the case study of iwi/hapū-local government engagement in creating and implementing the Ohiwa Harbour Strategy in New Zealand’s Eastern Bay of Plenty region between 2002- 2008. The strategy engagement, which culminated in a long-term plan to manage and conserve the Ohiwa harbour, is uniquely positioned for this investigation. It is often regarded by its iwi/hapū and local government stakeholders as a success story in iwi/hapū-government engagement. Using a critical qualitative research methodology informed by kaupapa Māori, the study sought to critically evaluate this exemplar of procedural inclusion at multiple levels. At an operational policy level, the research identified the factors that either facilitated or inhibited Māori inclusion in the strategy development process. At another, more substantive level, the study explored the politics of this engagement, and if the goals of procedural inclusion could accommodate the transformative claims of self-determination and kaitiakitanga made by iwi/hapū.
The analysis of interview data with key stakeholders and documents of the strategy process revealed that a range of factors enhance inclusive policymaking for Māori. At a practical level, legislative frameworks, commitment to Tikanga by all parties, and key strategic cultural brokers facilitated the inclusion of Māori, while limited capacity, fear of change and inter-tribal tensions hinder inclusion. The results also show, at another level, that the ability to productively participate in these engagement processes are framed by discursive politics – of the meanings and interpretations emanating from historical contexts, nature of power relationships, and of decisions regarding who represents whom and what is represented. In all, the study points to both advantages and limitations of procedural inclusion. Inclusive policymaking can open possibilities for better management of environmental resources, strengthening Māori political voice, and creating opportunities for livelihoods and with it greater economic and social inclusion. Equally, there are also limits of government-sponsored engagement.
Māori inclusion in policymaking, while positive, does not deliver opportunities for self determination or rangatiratanga in keeping with the Treaty principles of partnership.

text: Te Toi Poto, Te Toi Roa A Critical Evaluation of Māori-State Inclusion in the Ohiwa Harbour Strategy, Aotearoa New Zealand. In New Zealand, the State Owned Enterprises Act 1988 [SOE], Local Government Act 2002 [LGA], the Resource Management Act 1991 [RMA] require that government include the voices of Māori, and ensure their contribution to the decision-making processes of local authorities. Accordingly, central and local government have embraced the idea of inclusive partnership as part of policymaking processes informed by shared values both of government and iwi.
Thus, it is not uncommon to see consultations, partnerships and engagement between Māori-state on a range of issues in line with Tikanga and protocols of Māori culture. These transitions reflect contemporary critical policy scholarship that underscores the need to include marginalised voices policymaking, specifically through processes that reflect diverse values. Termed here as ‘procedural inclusion’, these efforts are framed within the wider goal of participatory democracy as part of the efforts to realise an inclusive society. The present research is a critical evaluation of the inclusion of Māori in the processes of policymaking, especially when those processes have been especially designed to be culturally sensitive.
This core objective is developed through the analysis of the case study of iwi/hapū-local government engagement in creating and implementing the Ohiwa Harbour Strategy in New Zealand’s Eastern Bay of Plenty region between 2002- 2008. The strategy engagement, which culminated in a long-term plan to manage and conserve the Ohiwa harbour, is uniquely positioned for this investigation. It is often regarded by its iwi/hapū and local government stakeholders as a success story in iwi/hapū-government engagement. Using a critical qualitative research methodology informed by kaupapa Māori, the study sought to critically evaluate this exemplar of procedural inclusion at multiple levels. At an operational policy level, the research identified the factors that either facilitated or inhibited Māori inclusion in the strategy development process. At another, more substantive level, the study explored the politics of this engagement, and if the goals of procedural inclusion could accommodate the transformative claims of self-determination and kaitiakitanga made by iwi/hapū.
The analysis of interview data with key stakeholders and documents of the strategy process revealed that a range of factors enhance inclusive policymaking for Māori. At a practical level, legislative frameworks, commitment to Tikanga by all parties, and key strategic cultural brokers facilitated the inclusion of Māori, while limited capacity, fear of change and inter-tribal tensions hinder inclusion. The results also show, at another level, that the ability to productively participate in these engagement processes are framed by discursive politics – of the meanings and interpretations emanating from historical contexts, nature of power relationships, and of decisions regarding who represents whom and what is represented. In all, the study points to both advantages and limitations of procedural inclusion. Inclusive policymaking can open possibilities for better management of environmental resources, strengthening Māori political voice, and creating opportunities for livelihoods and with it greater economic and social inclusion. Equally, there are also limits of government-sponsored engagement.
Māori inclusion in policymaking, while positive, does not deliver opportunities for self determination or rangatiratanga in keeping with the Treaty principles of partnership.

year: 2012