| 1. Construction and pure culture of three chiral filaments of Arthrospira ZJU013716S rRNA clustering analysis of left-handed strain ZJU0137 and left-handed strains of Arthrospira plantensis has been done. The result demonstrated the hereditary particularity of ZJU0137 in Arthrospira plantensis. Thus, further research has been done in ZJU0137, trying to construct the variation strain of helical chirality. The main results of the experiment are as follows:(1) Left-handed is the natural chirality of strain ZJU0137, however right-handed filament and no-handed filament were firstly constructed through the optimum of factors such as cultivation liquid, temperature and illumination. Meanwhile, pure culture of three chiral filaments are obtained at the same culture condition; (2) With the effect of the physical and chemical factor, the chirality of left-handed filaments is remairkably stable; at the same time, the variation of right-handed filament is easier affected by external conditions. This indicated that there was a inherent bias with the helical chirality in helical chirality filaments of ZJU0137, and its intrinsic orientation was left-handed. The chirality of no-handed filaments is also stable. (3) In the process of the construction and the cuture of the three kinds of chiral filaments we found that after seperating line filament it can been still cultured steadily and there was no reversal found; But in a cycle of isolation and culture,there was irregular reversal for the right-handed filament at the early period and probability of reversals is high. But the probability of reversal was becoming apparently lower over time and gradually the chirality wolud be stabilized. This indicated that the lose of the helical chirality in ZJU0137 and its rebuilding were of asymmetry, and the time of reversal was uncertain, the probability of reversal became smaller over time and gradually the chirality wolud be stabilized.2. Comparative research on Surface structure, Physiological & Biochemical Properties of three chiral filaments of Arthrospira platensis ZJU0137 On obtaining pure culture of three chiral filaments of ZJU0137, with the AFM and PAM technology, surface and apparence feature and photosynthetic characteristics were tested. On this basis, comparative research on photosynthetic pigments, amino acid composition and radiation resistance was done. There are the main results:(1) there is big difference of surface and appanrence feature for the three chiral filaments in nanomeasurement morphology, their surface roughness as follows: left-handed>no-handed>right-handed. (2) For the three helical chiral filaments, the maximal photochemical efficiency of PSII (Fv/Fm), photosynthetic efficiency (a), maximum electron transport rate (ETRmax), content of Chlorophyll a and carotenoid all obey the rule:left-handed>no-handed>right-handed, this result tallies with the growth curve determination, and saturation light intensity (Ik) showed an opposite tendency. It can been assumed that this phenomenon led from the using of illumination of chiral filaments and the aggregation state of some groups of filaments (3) There is difference in amino acid composition and proportation of chiral filaments,total content of the amino acid is left-handed>right-handed>no-handed, the content of single amino acids of no-handed filaments is lower than helical except cystine, the content of 70% single amino acids of right-handed filaments is lower than left-handed; propotion of amino acid and AAS evulation showed the nutritional value of the three helical chiral filaments:helical is better than no-handed, right-handed is better than left-handed. So in the angle of science of nutrition the experiment verified the theory of "straight was degradation of species". (4) Research on anti-radiation showed the sensitive degree of three chiral filaments to ray-irraditon:right-handed> no-handed>left-handed, and the IC50 is 2.1,2.2,2.3kGy, left-handed and no-handed filaments would keep their stable morphology in a condition of different radiation dosages, but to right-handed filament, the more radiation dosages given,the more likely it become left-handed. So it seems reasonable to assume that the change of the chirality is a self-protecting mechanism for adapting to abiotic or biotic stresses.3. Comparative research on protein expression differences among three chiral filaments of Arthrospira ZJU0137 In this chapter, technology of 2-DE and MOLDI-TOF MS was used for the research on protein differenec of the three chiral filaments. Following are the main results:(1) With SDS-PAGE preliminary analysis of water soluble protein of different chiral filaments has been done, it is found that does exsists clear difference of protein expression for different chiral filaments. At the protein bands with molecular weight of88,62,40,32,30,29,23 and 14.4 kDa, there is a difference in expression level of the three helical chirality。At the protein bands with molecular weight of 40 kDa the expression level of the three helical chirality is as follows:right-handed> no-handed>left-handed, which is in correspondence with surface roughness, growth, photosynthetic characteristics and ray-irraditon. It is assumed that those proteins has relation to the construction, growth and anti-irradiation of the chiral filaments (2) Based on the SDS-PAGE, with 2-DE different expressed proteins were separated,27 significant spots with dominant were found, besides, with MOLDI-TOF MS the protein is analysed and identified, and among them 26 protein spots were successfully identified. (3) By analysis of bioinformatics we can draw the conclusion: among the differentially expressed proteins 9 are related to photosynthesis,2 of them involve translation and transcription,2 of them involve sugar metabolism,2 of them involve cell wall and cell membrane synthesis,8 are related to other metabolism and the rest 3 are all hypothetical protein.4 kinds of proteins may be involved in the construction and maintenance of chiral filament of Arthrospira platensis.
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