Isolation Of Vacuole In Cyanobacteria

~#) S THESIS Abstract The question as to whether the cyanobacteria have vacuoles or can form vacuoles is still controversial. It was reported that vacuoles were formed only in the aged cells and were the sign of being death. Some others even pointed out that vacuoles were presented in the normally growing cells of cyanobacteria. However, it was not generally accepted that vacuole existed in cell of cyanobacteria since the isolation of the vacuole has never been achieved for extensive study. In recent years, in research of cyanobacterial protoplasts, Guo et al. have discovered both the salt-induced vacuoles and the non-induced vacuoles in the cells and achieved success in the isolation.For further study, we have selected six species of cyanobacteria and treated them with different environmental stress conditions. The results are reported as follow: Cultured in the presence of 0.O5molIL chlorinate, nitrate, sulphate and phosphate of K, Na and ammonium for 2 days, the cells of Anabaena sp. 595 inflated, vacuolized and performed longitudinal or unequational division; the trichomes fragmented and the number of heterocysts increased. And what抯 more, special contracted gramulum appeared in the cells when they were induced by animoniuin. In comparison, the cells were less affected by Ca2~ and Mg2~.While cultured in the medium containing 0.0 lmol/L NaC1 for long-term effect, the cell exhibited cyclic differentiation. It inflated and vacuolized firstly, then the pigment expanded and vacuolization disappeared, finally, the cell divided to normal size. In fact, the inflation and vacuolization appeared again in the following days, so the cycle continued. liZ. Six cyanobaceria were cultured in the presence of O.O5mollL NaCl~ KNO3~ (NH4)2SO4~ MgSO4 and CaC12 for vacuole induction, and produced different effects. Anabaena sp.595 was the most sensitive , vacuole could be induced by all salts we tested. In contrast, no salts could induce cell vacuolization in Oscillatoria animlis 284 and Spirulina maxima 438. While Nostoc sp.9 6.. Plectonema boryanum246 and Scytonema hofmanni248 were the relatively sensitive strains, only NaC 1.. KNO3.. or (NI{4)2S04 had the inducing effect on them. The induced vacuole was examed by pressing the sample, it was spherical and transparent in the scope of phase microscope. Two heavy metals, including mercury and cadmium, and two trace iii elements ,such as copper and zinc were used for vacuole induction in the cells of A.sp 595, Pboryanum 246 and S.hofmanni 248. 0.lum mercury induced vacuoles in all the three tested cyanobacteria, while 5.Oum cadmium in A.sp 595, O.Sum cadmium in P.boryanum 246 and S.hofinanni 248. The inducing effect of mercury was more obvious than that of cadmium. In comparision, no severe difference existed in inducing function of the two trace elements copper and zinc. For vacuole induction, A.sp 595 needed l.Oum copper and zinc, which S. hofinanni 248 needed 0.Sum, and Pboiyanum 246 needed 1 .Oum copper and 0.Sum zinc. The induced vacuole was examed by pressing the sample, it was spherical and transparent in the scope of the phase microscope. l~. Six species or strains of cyanobacteria, A.sp. 595, P boryanum 246, S. hofinanni 248, N. sp.96, 0. animlis284 and S.