| In this paper, the pyrenoid ultrastructure of Ch]ajnydomonasreinhardtii~. Ch]orel]a spp.64O9O9~ Enteromaorpha c]athrata and Porphyra yezoensis have been observed, and their key enzymes of photosynthesis, Rubisco, Rubisco activase and carbonic anhydrase molecule localization with gold immunolocalization technology and the algal CO2 concentrating mcchanism(CCM) have been studied. With gene transferring technology, the codA gene for choline oxidase was transferred and expressed in tobacco, and the stress photosynthetic physiology of transgenic plants was measured and analyzed. Algal pyrenoid is composing of Rubisco. There were 1-2 emlargement thylakoids which penetrated along the middle of the pyrenoid, called as portrait channel. There were several connectors between the pyrenoids and the chloroplast stroma. And there were several thylakoids stocked in the pyrenoids of Chlamydomonas reinhardtii. Those may be the structure for pyrenoid photosynthesis. The starch sheath embedded the pyrenoid. The pyrenoid could be divided into three types according to their structure. With the antibody raised against Rubisco large subunit from Chlorella protothecoides , there was one band in the western blotting map from SDS-PAGE and Native-PAGE of Chlorella spp.64O909 Enteromorpha clathrata and Porphyra yezoensis, which indicating they shared high homogenous, and the large subunits of the Rubisco was about 55kDr. The results of gold immunolocalization showed the Rubisco distributed in the pyrenoid (90-95%)and starch sheath region (4-8%), only few Rubisco located in the stroma of chloroplasts. Especially, the Rubisco activase as well as whole enzyme of Rubisco were distributed in the starch sheath and the surface of pyrenoid. It was demonstrated the pyrenoid had close relationship with photosynthesis. The important components of algal CCM included periplasmic carbonic anhydrase (pCA), chloroplast carbonic anhydrase (chCA) and pyrenoid. With antibody raised against pCA from 5 Chlamydomonas reinhardtii, the result of gold imniunolocalization showed the pCA were distributed on the wall, and the space between the wall and membrane as well as outside the cell wall. And the Cali3 was showed to distribute on the thylakoids by the gold immunolocalization with antibody raised against Cah3 from its cDNA cloned from Chlamydomonas reinhardtii (Karisson, et al, 1997). The results of the activity determining of the chCA from chloroplasts of Chlamydomonas reinhardtii showed there were about 3 types of the chCA in chloroplast: one was in the stroma, another was on the membrane which was inhibited by the inhibitor AZ, the third also was on the membrane but insensitive to inhibitor. The comparing experiment of CO2 induction and pH regulation in the medium of Chlamydomonczs reinhardtii showed the CA activity could be induced by the simple pH change as the CO2 induction. It indicated the increasing of CA activity from low-Ci cells might be controlled by the pH regulation. Betaine is one of the compatible solutes that accumulate in the chloroplasts of certain halo tolerant plants when they are exposed to some stress. The coci4 gene for choline oxidase, which converts choline into betaine and cloned from a soil bacterium Arthrobactor glob!formis, now has been transformated and expressed in tobacco by the Agrobatcterium-method through the binary plasmid pGAHIcodA. The pGAHlcodA was carried with Knit and Hygr, and the sequence of transit peptide from Rubisco small subunit gene (rbcS) was inserted between 35S promoter and...
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