Carotenoid Distribution in Living Cells of Haematococcus pluvialis (Chlorophyceae)
Open Access
- 6 September 2011
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 6 (9), e24302
- https://doi.org/10.1371/journal.pone.0024302
Abstract
Haematococcus pluvialis is a freshwater unicellular green microalga belonging to the class Chlorophyceae and is of commercial interest for its ability to accumulate massive amounts of the red ketocarotenoid astaxanthin (3,3′-dihydroxy-β,β-carotene-4,4′-dione). Using confocal Raman microscopy and multivariate analysis, we demonstrate the ability to spectrally resolve resonance–enhanced Raman signatures associated with astaxanthin and β-carotene along with chlorophyll fluorescence. By mathematically isolating these spectral signatures, in turn, it is possible to locate these species independent of each other in living cells of H. pluvialis in various stages of the life cycle. Chlorophyll emission was found only in the chloroplast whereas astaxanthin was identified within globular and punctate regions of the cytoplasmic space. Moreover, we found evidence for β-carotene to be co-located with both the chloroplast and astaxanthin in the cytosol. These observations imply that β-carotene is a precursor for astaxanthin and the synthesis of astaxanthin occurs outside the chloroplast. Our work demonstrates the broad utility of confocal Raman microscopy to resolve spectral signatures of highly similar chromophores in living cells.Keywords
This publication has 49 references indexed in Scilit:
- In vivo lipidomics using single-cell Raman spectroscopyProceedings of the National Academy of Sciences of the United States of America, 2011
- Pigment composition, optical properties, and resistance to photodamage of the microalga Haematococcus pluvialis cultivated under high lightRussian Journal of Plant Physiology, 2011
- Raman Spectroscopy Analysis of Botryococcene Hydrocarbons from the Green Microalga Botryococcus brauniiPublished by Elsevier BV ,2010
- Raman Microspectroscopy of Individual Algal Cells: Sensing Unsaturation of Storage Lipids in vivoSensors, 2010
- Effect of photon flux densities on regulation of carotenogenesis and cell viability of Haematococcus pluvialis (Chlorophyceae)Journal of Applied Phycology, 2009
- In vivo hyperspectral confocal fluorescence imaging to determine pigment localization and distribution in cyanobacterial cellsProceedings of the National Academy of Sciences of the United States of America, 2008
- In vivoprediction of the nutrient status of individual microalgal cells using Raman microspectroscopyFEMS Microbiology Letters, 2007
- Automated Analysis of SEM X-Ray Spectral Images: A Powerful New Microanalysis ToolMicroscopy and Microanalysis, 2003
- Hyper-accumulation of astaxanthin in a green algaHaematococcus pluvialis at elevated temperaturesBiotechnology Letters, 1994
- Vibrational spectra of some carotenoids and related linear polyenes. Raman spectroscopic studyJournal of the American Chemical Society, 1973