TY - JOUR
T1 - Proteomic analysis of molecular response to oxidative stress by the green alga Haematococcus pluvialis (Chlorophyceae)
AU - Wang, Sheng Bing
AU - Chen, Feng
AU - Sommerfeld, Milton
AU - Hu, Qiang
N1 - Funding Information:
Acknowledgements We thank Dr. Ken Hoober for his encouragement and advice, and Dr. Dan Brune for assistance with MALDI– TOF mass spectrometry analysis. The US National Science Foundation (Grant CHE-0131222) is gratefully acknowledged for providing funding for the mass spectrometer used in this work.
PY - 2004/11
Y1 - 2004/11
N2 - Rapidly growing, green motile flagellates of Haematococcus pluvialis can transform into enlarged red resting cysts (aplanospores) under oxidative stress conditions. However, it is not known what initial molecular defense mechanisms occur in response to oxidative stress, and may ultimately lead to cellular transformation. In this study, global-expression profiling of cellular proteins in response to stress was analyzed by two-dimensional gel electrophoresis, image analysis, and peptide mass fingerprinting. Oxidative stress was induced in cultures of green flagellates by addition of acetate and Fe2+, and exposure to excess light intensity. Overall, 70 proteins were identified with altered expression patterns following stress induction. Some key proteins involved in photosynthesis and nitrogen assimilation were down-regulated, whereas some mitochondrial respiratory proteins were transiently up-regulated after the onset of stress. Most of the identified proteins, particularly those from the families of superoxide dismutase, catalase, and peroxidase, were transiently up-regulated, but reverted to down-regulation during the 6 days of stress. On the other hand, cellular accumulation of the antioxidant astaxanthin occurred well after initiation of oxidative stress and reached its maximum cellular level after six or more days of stress. It appears that the early stress response involves multiple enzymatic defense processes that play a critical role upon onset of stress and also during the early transition of green vegetative cells to red cysts. As cyst development continues, the intensive, enzyme-mediated initial responses were largely replaced in mature red cysts by accumulation of the molecular antioxidant astaxanthin. This study provides the first direct evidence for a massive, and concerted up-regulation of multiple antioxidative defense mechanisms, both spatially and temporarily, to protect H. pluvialis cells against oxidative stress.
AB - Rapidly growing, green motile flagellates of Haematococcus pluvialis can transform into enlarged red resting cysts (aplanospores) under oxidative stress conditions. However, it is not known what initial molecular defense mechanisms occur in response to oxidative stress, and may ultimately lead to cellular transformation. In this study, global-expression profiling of cellular proteins in response to stress was analyzed by two-dimensional gel electrophoresis, image analysis, and peptide mass fingerprinting. Oxidative stress was induced in cultures of green flagellates by addition of acetate and Fe2+, and exposure to excess light intensity. Overall, 70 proteins were identified with altered expression patterns following stress induction. Some key proteins involved in photosynthesis and nitrogen assimilation were down-regulated, whereas some mitochondrial respiratory proteins were transiently up-regulated after the onset of stress. Most of the identified proteins, particularly those from the families of superoxide dismutase, catalase, and peroxidase, were transiently up-regulated, but reverted to down-regulation during the 6 days of stress. On the other hand, cellular accumulation of the antioxidant astaxanthin occurred well after initiation of oxidative stress and reached its maximum cellular level after six or more days of stress. It appears that the early stress response involves multiple enzymatic defense processes that play a critical role upon onset of stress and also during the early transition of green vegetative cells to red cysts. As cyst development continues, the intensive, enzyme-mediated initial responses were largely replaced in mature red cysts by accumulation of the molecular antioxidant astaxanthin. This study provides the first direct evidence for a massive, and concerted up-regulation of multiple antioxidative defense mechanisms, both spatially and temporarily, to protect H. pluvialis cells against oxidative stress.
KW - Astaxanthin
KW - Haematococcus
KW - Oxidative stress
KW - Protein expression
KW - Proteomics
KW - Stress response
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U2 - 10.1007/s00425-004-1323-5
DO - 10.1007/s00425-004-1323-5
M3 - Article
C2 - 15258760
AN - SCOPUS:11144320702
SN - 0032-0935
VL - 220
SP - 17
EP - 29
JO - Planta
JF - Planta
IS - 1
ER -