title: Structural characterization of new microcystins containing tryptophan and oxidized tryptophan residues

authors: Puddick, Jonathan

subjects: microcystin

abstract: Microcystins are cyclic peptides produced by cyanobacteria, which can be harmful to humans and animals when ingested. Eight of the (more than) 90 microcystin variants presently characterized, contain the amino acid tryptophan. The well-researched oxidation products of tryptophan; kynurenine, oxindolylalanine, and N-formylkynurenine, have been previously identified in intact polypeptides but microcystin congeners containing oxidized tryptophan moieties have not been reported. Liquid chromatography-tandem mass spectrometric analysis of an extract of Microcystis CAWBG11 led to the tentative identification of two new tryptophan-containing microcystins (MC‑WAba and MC-WL), as well as eight other microcystin analogs containing kynurenine, oxindolylalanine and N‑formylkynurenine (Nfk). Investigation of one of these congeners (MC‑NfkA) by nuclear magnetic resonance spectroscopy was used to verify the presence of Nfk in the microcystin. Liquid chromatography-mass spectrometry analysis of a tryptophan oxidation experiment demonstrated that tryptophan-containing microcystins could be converted into oxidized tryptophan analogs and that low levels of oxidized tryptophan congeners were present intracellularly in CAWBG11. MC-NfkR and MC-LNfk were detected in standards of MC-WR and MC-LW, indicating that care during storage of tryptophan-containing microcystins is required.

text: Structural characterization of new microcystins containing tryptophan and oxidized tryptophan residues Microcystins are cyclic peptides produced by cyanobacteria, which can be harmful to humans and animals when ingested. Eight of the (more than) 90 microcystin variants presently characterized, contain the amino acid tryptophan. The well-researched oxidation products of tryptophan; kynurenine, oxindolylalanine, and N-formylkynurenine, have been previously identified in intact polypeptides but microcystin congeners containing oxidized tryptophan moieties have not been reported. Liquid chromatography-tandem mass spectrometric analysis of an extract of Microcystis CAWBG11 led to the tentative identification of two new tryptophan-containing microcystins (MC‑WAba and MC-WL), as well as eight other microcystin analogs containing kynurenine, oxindolylalanine and N‑formylkynurenine (Nfk). Investigation of one of these congeners (MC‑NfkA) by nuclear magnetic resonance spectroscopy was used to verify the presence of Nfk in the microcystin. Liquid chromatography-mass spectrometry analysis of a tryptophan oxidation experiment demonstrated that tryptophan-containing microcystins could be converted into oxidized tryptophan analogs and that low levels of oxidized tryptophan congeners were present intracellularly in CAWBG11. MC-NfkR and MC-LNfk were detected in standards of MC-WR and MC-LW, indicating that care during storage of tryptophan-containing microcystins is required.

year: 2013

title: Planners and the conservation of biological heritage: Implications for New Zealand and Australia

authors: Jay, Grace Mairi M.

subjects: conservation

abstract: The aim of this paper is to encourage greater attention by planners to conservation of native or indigenous biodiversity, and to the skills and knowledge required for this endeavour. This paper argues that, in order to be effective, planners need to develop methods and principles of planning that support the long-term survival of native species and ecosystems. To do so, they will need to work with ecologists, biologists, and land managers, and bring new areas of ecological understanding to their traditional skills. They will also have to demonstrate that they have the skills they claim to have. Moreover, since conservation of biodiversity frequently requires the maintenance or restoration of ecological processes a change in the common focus of planning on development approval with limited monitoring or enforcement, is required.

text: Planners and the conservation of biological heritage: Implications for New Zealand and Australia The aim of this paper is to encourage greater attention by planners to conservation of native or indigenous biodiversity, and to the skills and knowledge required for this endeavour. This paper argues that, in order to be effective, planners need to develop methods and principles of planning that support the long-term survival of native species and ecosystems. To do so, they will need to work with ecologists, biologists, and land managers, and bring new areas of ecological understanding to their traditional skills. They will also have to demonstrate that they have the skills they claim to have. Moreover, since conservation of biodiversity frequently requires the maintenance or restoration of ecological processes a change in the common focus of planning on development approval with limited monitoring or enforcement, is required.

year: 1999

title: Mana motuhake ā-raraunga: datafication and social science research in Aotearoa

authors: Kukutai, Tahu

abstract: Social practices, interactions and relations are increasingly being turned into data, driven by technologies that enable new methods of data accumulation, digitisation, integration and manipulation (Taylor and Broeders 2015; Couldry and Yu 2018; Mann and Daly 2019). This ‘datafication’ is not only transforming social relations, it is also reshaping social science through the generation of datasets that open up new avenues for research and methodological development (van Dijck 2014) and generating debate about the relationships between data, digitalisation, ethics and human wellbeing (boyd and Crawford 2012; Mittelstadt and Floridi 2016; O’Neil 2016; Eubanks 2018).

text: Mana motuhake ā-raraunga: datafication and social science research in Aotearoa Social practices, interactions and relations are increasingly being turned into data, driven by technologies that enable new methods of data accumulation, digitisation, integration and manipulation (Taylor and Broeders 2015; Couldry and Yu 2018; Mann and Daly 2019). This ‘datafication’ is not only transforming social relations, it is also reshaping social science through the generation of datasets that open up new avenues for research and methodological development (van Dijck 2014) and generating debate about the relationships between data, digitalisation, ethics and human wellbeing (boyd and Crawford 2012; Mittelstadt and Floridi 2016; O’Neil 2016; Eubanks 2018).

year: 2019