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Summary
Metadata record for data from AAS (ASAC) project 3042.

Public Summary:
Ozone depletion above Antarctica has caused large increases in springtime UVB radiation (UVBR) and recovery of the ozone layer is not expected until 2060. We have shown that increased UVBR is likely to have more negative effects on the endemic moss, Schistidium antarctici, than on two co-occurring ... cosmopolitan species Ceratodon purpureus and Bryum pseudotriquetrum. This is probably due to differences in their ability to screen UVBR but we need to fully characterise the UV absorbing compounds in each species, and their cellular location, to confirm this. Our team of chemists and biologists will fully characterise these potentially novel UV screens.

Project objectives:
This project brings together chemists and biologists to fully characterise the UV screens in the Antarctic endemic moss Schistidium antarctici, and two co-occurring cosmopolitan species Ceratodon purpureus and Bryum pseudotriquetrum.
Our specific aims are:
1. to extract and separate soluble and cell wall UV-B screening chemical compounds from the three moss species,
2. to identify the precise chemical structure of these compounds and their cellular location, and
3. to measure and compare the UV-B absorbing ability of the different chemical compounds.

Taken from the 2008-2009 Progress Report:
Progress against objectives:
1. to extract and separate soluble and cell wall UV-B screening chemical compounds from the three moss species,

We have developed a methodology for efficient extraction and partitioning of the UV-B screening compounds using local C. purpureus. See attached flow chart.

2. to identify the precise chemical structure of these compounds and their cellular location,

Using HPLC we have provisionally identified a number of bisflavones and some derivatives of benzoic acids as components of the UV-absorbing compounds in Ceratodon purpureus. Final confirmation of the exact structure of these compounds is currently underway using LC-MS and spectroscopic methods (e.g. NMR). Further separation of other UV-active compounds is continuing.

3. to measure and compare the UV-B absorbing ability of the different chemical compounds.

This will be performed once we have confirmed the exact identity of the compounds above.

Geographic Coverage Spatial coordinates   

N: -66.24

S: -66.32

E: 110.56

W: 110.48

Temporal Coverage

Start Date: 2008-09-30 Stop Date: 2009-03-31

Location Keywords

CONTINENT > ANTARCTICA GEOGRAPHIC REGION > POLAR

Science Keywords

BIOLOGICAL CLASSIFICATION > PLANTS > MOSSES/HORNWORTS/LIVERWORTS ATMOSPHERE > ATMOSPHERIC RADIATION > ULTRAVIOLET RADIATION

ISO Topic Category

BIOTA ENVIRONMENT

Platform

FIELD INVESTIGATION FIELD SURVEYS

Instrument

HPLC > High-Performance Liquid Chromatograph

Quality
The values provided in temporal and spatial coverage are approximate only.

Taken from the 2008-2009 Progress Report:
Laboratory activity/analysis:
We have developed a methodology for efficient extraction and partitioning of the UV-B screening compounds in these mosses.

Confocal microscopy was used to examine localisation of phenolics in three Antarctic ... bryophyte species and also to investigate the efficiency of the various extraction techniques in removing phenolics from C. purpureus. Confocal fluorescence images showed C. purpureus had 2-fold higher amounts of cell wall-bound than intracellular phenolics whereas Bryum pseudotriquetrum contained approximately half the amount of cell wall-bound than intracellular phenolics. In the Antarctic liverwort Cephaloziella exiliflora phenolics were predominantly intracellular with little bound to the cell walls. These results indicate that B. pseudotriquetrum and C. exiliflora rely more on intracellular UV screens than C. purpureus. In addition, confocal microscopy demonstrated that the intracellular phenolics in both B. pseudotriquetrum and C. purpureus are most likely to be localised within vacuoles.

We have also ascertained that the alkali hydrolysis extraction method is successful in extracting phenolic compounds bound to cell walls of C. purpureus although we are currently trying to modify this method to avoid the use of Sodium dodecyl sulfate since this interferes with identification of the compounds.

Using subsequent chromatography techniques, aromatic compounds, unsaturated fatty acids and an unsaturated alcohol were identified as responsible for some of the high UV activity observed in the cell wall extracts. Using HPLC we have provisionally identified a number of bisflavones and some derivatives of benzoic acids as components of the UV-absorbing compounds in C. purpureus using HPLC. We have been concentrating on the cell wall fraction in this species but these compounds appear to be in both the cell wall and intracellular compartments.

Final confirmation of the exact structure of these compounds is currently underway using LC-MS and spectroscopic methods (e.g. NMR). Once we have confirmed the identity of the compounds we can assess their relative strength as UV screens and also their precise location within the cell.

Further separation of other UV-active compounds is continuing for Bryum pseudotriquetrum.

Access Constraints
These data are not yet publicly available.

Use Constraints
Please follow instructions listed in the citation reference provided at the URL below when using these data.

Ancillary Keywords

UVB ozone layer moss Schistidium antarctici Ceratodon purpureus Bryum pseudotriquetrum climate change

Data Set Progress

IN WORK

Data Center

Australian Antarctic Data Centre, Australia Data Center URL: http://data.aad.gov.au Data Center Personnel Name: DATA OFFICER AADC Phone: +61 3 6232 3244 Fax: +61 3 6232 3351 Email: metadata at aad.gov.au Contact Address: Australian Antarctic Division 203 Channel Highway City: Kingston Province or State: Tasmania Postal Code: 7050 Country: Australia

Personnel

SHARON ROBINSON Role: INVESTIGATOR Role: TECHNICAL CONTACT Phone: +61 2 4221 5753 Fax: +61 2 4221 4135 Email: sharonr at uow.edu.au Contact Address: Department of Biological Sciences University of Wollongong Northfields Ave City: WOLLONGONG Province or State: New South Wales Postal Code: 2522 Country: Australia DAVE CONNELL Role: DIF AUTHOR Phone: +61 3 6232 3244 Fax: +61 3 6232 3351 Email: dave.connell at aad.gov.au Contact Address: Australian Antarctic Division 203 Channel Highway City: Kingston Province or State: Tasmania Postal Code: 7050 Country: Australia

Related URL

Link: VIEW PROJECT HOME PAGE Description: Public information for ASAC project 3042 Link: VIEW RELATED INFORMATION Description: Citation reference for this metadata record and dataset

Publications/References
1. Waterman, M. 2008. Ultraviolet protective mechanisms in the survival of Antarctic Ceratodon purpureus and two other Antarctic bryophytes. BBiotech Honours thesis. University of Wollongong

2. Turnbull, J.D., Leslie, S.J., Robinson, S.A. (2009) Desiccation protects Antarctic mosses from UV –B induced DNA damage. Functional Plant Biology 36 214-221

3. Turnbull, J.D., Robinson, S.A. (2009) Accumulation of DNA damage in Antarctic mosses: correlations with ultraviolet-B radiation, temperature and turf water content vary among species. Global Change Biology 15 319-329.

4. Newsham, KK., Robinson, S.A. (2009) Responses of plants in polar regions to UV-B radiation: a meta-analysis. Global Change Biology accepted 13/3/09

Creation and Review Dates

DIF Creation Date: 2009-04-20 Last DIF Revision Date: 2009-04-24

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