绿硫细菌色素的高效液相色谱分析及其应用

绿硫细菌(green sulfur bacteria)的特征色素及其衍化产物,如细菌叶绿素d、细菌叶绿素e、绿硫菌烯(chlorobactene)和异海绵烯(isorenieratene)等可以作为标志物,指示水体真光层的无氧事件,以及水生生态系统在缺氧环境下的演变过程。但是,由于缺少色素标准品,相关研究工作受到制约。为此,本研究培养了两种典型绿硫细菌——Chlorobium phaeovibrioides(DSM269,褐色菌株)和Prosthecochloris vibrioformis(DSM260,绿色菌株),并应用高效液相色谱仪分析了两种细菌所产色素情况。结果在两株细菌中检测到了细菌叶绿素d(DSM260)、细菌叶绿素e(DSM269)和异海绵烯(DSM269),并获得各类色素的特征吸收光谱和保留时间。依据上述方法,对底层水体缺氧问题突出的长江口南部邻近海域表层沉积物样品进行了初步分析,但未检测到绿硫细菌色素。考虑到长江口邻近海域底层水体缺氧问题正在不断加剧,有必要将绿硫细菌色素作为一类重要的指标作进一步研究。

ANALYSIS ON PIGMENTS IN GREEN SULFUR BACTERIA WITH HIGH PERFORMANCE LIQUID CHROMATOGRAPHY AND THE APPLICATION

Diagnostic pigments of green sulfur bacteria(GSB), such as bacterialchrolophyll d, bacterialchrolophyll e, chlorobactene, isorenieratene, etc, can be used as biomarkers to study anoxic events in a euphotic zone and changes of aquatic ecosystems under anoxic condition. In this study, two representative GSB species, Chlorobium phaeovibrioides(DSM269, brown-colored strain) and Prosthecochloris vibrioformis(DSM260, green-colored strain) were cultured, and their pigments were analyzed in high performance liquid chromatography. Bacterialchrolophyll d was detected from strain DSM 260, and bacterialchrolophyll e and isorenieratene were detected from DSM 269. The retention time and characteristic adsorption spectra were recorded for these pigments. For application, surface sediment samples collected from the sea area south of the Changjiang River mouth, where seasonal hypoxia in the last decade was reported, were analyzed. However, no GSB pigments could be detected. Considering the deteriorating trend of seasonal hypoxia in the sampling region, GSB pigments can be applied as an index to the hypoxia in this region.