title: Raman spectroscopic analysis of a desert cyanobacterium Nostoc sp. in response to UVB radiation.
abstract: Cyanobacteria are capable of tolerating environmental extremes. To survive in extreme environments, cyanobacteria have developed the capability to adapt to a variety of stresses. For example, cyanobacteria have adopted a number of strategies with which to survive UV stress, including expression of UV-screening pigments and antioxidant systems. We have previously shown that several antioxidants are significantly expressed in Nostoc sp. by UVB irradiation. We report here that the content of UV-responsive biomarkers such as β-carotene and scytonemin can be easily detected by Fourier transform Raman spectroscopy with use of a small sample size and that the content of β-carotene is dependant on the UVB intensity and exposure time. Our results indicate that Raman spectroscopy may be a helpful tool to analyze UV-protective molecules of cyanobacterium in astrobiological studies without access to large sample sizes and complicated extractions, which are needed by other analytical techniques such as high-performance liquid chromatography and mass spectrometry.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan, China.
authors.forename: Gaohong
authors.initials: G
authors.lastname: Wang
authors.forename: Zongjie
authors.initials: Z
authors.lastname: Hao
authors.forename: Zebo
authors.initials: Z
authors.lastname: Huang
authors.forename: Lanzhou
authors.initials: L
authors.lastname: Chen
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Li
authors.forename: Chunxiang
authors.initials: C
authors.lastname: Hu
authors.forename: Yongding
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D018559:Exobiology / Q000379:methods; D007211:Indoles / Q000378:metabolism; D046937:Nostoc / Q000378:metabolism* / Q000528:radiation effects*; D010636:Phenols / Q000378:metabolism; D010788:Photosynthesis; D010860:Pigments, Biological / Q000378:metabolism; D013059:Spectrum Analysis, Raman / Q000379:methods*; D014466:Ultraviolet Rays; D019207:beta Carotene / Q000378:metabolism
chemical_list: D000975:Antioxidants; D007211:Indoles; D010636:Phenols; D010860:Pigments, Biological; D019207:beta Carotene; C083368:scytonemin