鱼腥藻7120异形胞分化的调节及细胞蛋白的变化  

THE REGULATION OF HETEROCYST DIFFERENTIATION AND CHANGES OF CELL PROTEINS IN ANABAENA 7120

作　　者：王业勤[1] 杨林[1] 冯渤[1] 

机构地区：[1]中国科学院水生生物研究所

出　　处：《水生生物学报》1987年第1期41-51,共11页Acta Hydrobiologica Sinica

摘　　要：分离了有固氮活性的异形胞,它的可溶部分和膜部分的吸收光谱与营养细胞明显不同。SDS凝胶电泳图谱表明,营养细胞中存在的可溶蛋白,在异形胞中有一半左右被降解,最明显的是藻蓝蛋白。异形孢具有与营养细胞共同的肽带,但也合成了一些新的多肽。异形胞可溶蛋白有五条最主要的肽带,表观分子量约为73K,54K,48K,41K和34K。膜蛋白中至少有2个多肽带(41K,35K)在营养细胞膜蛋白中是缺少的。异形胞分化过程伴随着细胞蛋白酶活性的消长。1mmol/L甲苯磺酰氟(PMSF)完全封锁异形胞的分化。而利福平(0.02μg/ml)和酪蛋白水解物(40μg/ml)使异形胞分化频率增加近一倍,与此同时,营养细胞可溶蛋白的二个多肽(72K和56K)含量大大增加。Heterocysts with higher nitrogen-fixing activity were isolated from Anabaena 7120. The absorbance spectra of their soluble and membrane fractions are different obviously from that of the vegetative cells. The polypeptide compositions in soluble and membrane fractions of these two types of cells were compared by means of SDS-polyacrylamide gel electrophoresis. The results show that about one half of the soluble proteins in vegetative cell are degraded after the heterocyst is differentiated. Heterocyst has polypeptides as those in vegetative cell but it also synthesizes some new polypeptides.The soluble proteins of heterocyst show five major polypeptide bands with apparent molecular weights of 73000, 54000, 48000, 41000 and 34000. In the membrane proteins of heterocyst, at least two polypeptide bands having apparent molecular weights of 41000 and 35000 are deficient in membrane proteins of vegetative cellThe process of heterocyst development is correlated with the fluctuation of intracellular protease activity. Thus, the activity increases rapidly after differentiation initiation and reduces to its original level when the process ceases. Phenylmethylsulfonylfluoride was found to block the formation of heterocyst, whereas rifampicin and casein hydrolysate may double the differentiated frequency of the heterocyst. In the latter situation, two polypeptide bands with apparent molecular weights of 72000 and 56000 in soluble proteins of vegetative cell are deeply stained. The possibility of using the stained bands as a biochemical marker is discussed in this paper.

关 键 词：异形胞 营养细胞 鱼腥藻 膜蛋白 多肽 藻蓝蛋白 凝胶电泳 分化 调节 SDS 

分 类 号：Q949.22[生物学—植物学] Q959