产氢红杆菌类胡萝卜素突变株的诱变和筛选

用紫外线照射和氯化锂夹层平板培养法对产氢红杆菌(Rhodobacter sp.R7)进行复合诱变,分离获得了一株产氢效率提高的类胡萝卜素突变株R726.该突变株在表观特征、光谱学特征、色谱特征、生长和产氢性能等方面与出发菌株有明显不同,但16S rDNA序列一致.R726菌株有550 nm类胡萝卜素特征性吸收峰,类胡萝卜素组成上比出发菌株少一黄色类胡萝卜素组分,生长和产氢性能均高于出发菌株,产氢效率比出发菌株提高了33.3%,类胡萝卜素含量比出发株提高了53.8%.

The Mutagenesis and Screening of Carotenoid Mutant in Hydrogen-producing Photosynthetic Bacteria

Mutagenesis and screening of hydrogen-producing photosynthetic bacteria, Rhodobacter sp. R7 strain, was investigated by using the combination mutation of ultraviolet ray and LiCl and layer plating methods. A carotenoid mutant named R726 strain was obtained. The plate phenotype properties in carotenoid mutant were different from that of parent strains. Living cells spectra showed that absorption peak of 550 nm was appeared in carotenoid mutant, but not in parent strain. The absorption spectra of extraction of pigment further confirmed the difference of carotenoid composition between the mutant and parent strains. The result of TLC on silica gel plate showed that mutant has a lack of yellow carotenoid composition which occurs in parent strain. H2 productivity and biomass in carotenoid mutant was higher than that of parent strain. These results revealed that mutant has a modified carotenoid biosynthesis pathway.