盐度对耐盐荚膜红细菌光合色素组分积累的调控作用  

Regulation of Salinity on Photosynthetic Pigments of Halotolerant Rhodobacter capsulatus Strain XJ-1

作　　者：林志华[1] 赵春贵[2] 杨素萍[1,2] 

机构地区：[1]山西大学生命科学学院,山西太原030006 [2]华侨大学生物工程与技术系,福建厦门361021

出　　处：《山西大学学报（自然科学版）》2014年第2期299-304,共6页Journal of Shanxi University(Natural Science Edition)

基　　金：国家自然科学基金(31070054;31270106);福建省自然科学基金(2012J01136)

摘　　要：以荚膜红细菌（Rhodobacter capsulatus）XJ-1为研究对象，在光照厌氧条件下，采用吸收光谱法、薄层层析（TLC）法和图像灰度分析法研究了NaCl对菌体生长、类胡萝卜素和细菌叶绿素生物合成的调控作用。结果表明：0～0．2mol／LNaCl范围内，随盐度增加，菌体生长速率、最终生物量以及菌体积累的细菌叶绿素（BChl）n和类胡萝卜素（Car）含量升高，继续增加盐度，菌体的生长速率、最终生物量以及菌体积累的BChln和Car含量又逐渐降低。未添加Nacl时，菌体细胞主要积累5种色素组分，分别为BChla、脱镁细菌叶绿素（Bphe）、球形烯（SE）、球形烯酮（SO）和羟基球形烯（0H—SE），其中Bphe和OH—SE相对含量很低；但当添加0．2～0．4mol／LNaCl时，菌体额外积累了一种Bphe组分。随NaCl浓度增加，菌体积累的BChla和SE的相对含量降低，2种Bphe组分的相对含量则增加，而OH—SE和SO则呈先升后降的趋势。由此可见，随着盐度的变化，菌体光合色素的积累量与菌体的生长相关联，光舍色素的组分和相对含量也随之发生了规律性的变化。The effect of NaCI on cells growth and photosynthetic pigment biosynthesis in halotolerant Rhodobacter capsulatus XJ-1 under anaerobic light conditions was investigated using spectrophotometry, thin layer chromatography and image gray intensity analysis. The results showed that bacteria growth rate, the final biomass and the contents of bacteriochlorophylls and carotenoids increased with the increasing concentrations of NaCl within 0-0.2 mol/L. However,the growth rate,the final biomass and the accumulation yields of bacteriochlorophylls and carotenoids gradually decreased with further increasing NaCl con- centrations. R. capsulatus XJ-1 could accumulate bacteriochlorophyll a, bacteriopheophytin, OH-spheroidene,spheroidenone and spheroidene when grown in the absence of NaC1, and the relative contents of bacteriopheophytin and OH-spheroidene were lower. However,in the presence of 0.2-0.4 mol/L NaCl, strain XJ-1 also accumulated an additional bacteriopheophytin in addition to the mentioned above pigments. With the increasing concentrations of NaCl, the relative contents of bacteriochlorophylls and spheroidene decreased,whereas two bacteriophaeophytins increased,the relative contents of OH-spheroidene and sphe- roidenone firstly increased and then decreased. This work indicated that the accumulation of photosynthetic pigment was related with the growth of bacteria, and the composition and relative content of accumulated pigments varied in the change of salinity in Rhodobacter capsulatus XJ-1.

关 键 词：盐度 荚膜红细菌 细菌叶绿素 类胡萝卜素 

分 类 号：Q935[生物学—微生物学]