1. 毕业设计（论文）的内容和要求

本课题从菌种筛选出发，以获得四氢嘧啶高产菌，并对其发酵条件进行优化，提高产量，为日后大规模工业化生产提供可能。

2. 参考文献

[1] Galinski E A,Pfeiffer H P,et al.1,4,5,6-Tetrahydro-2-methyl-4-pyrimidinecar boxylic acid. A novel cyclic Amino acid from halophilic phototrophic bacteria of the genus Ectotiorhodospira.Eur J Biochem,1985,149:135-139. [2] Martin D D,Bartlett D H,Roberts M F. Solute accumulation in the deep-sea bacterium Photobacterium profundum. Extremophiles,2002,6:507-514. [3] Silva Z,Borges N,Martins L O,et al.Combined effect of the growth temperature and salinity of the meduim on the accumulation of the compatible solutes by Rhodothermus marinus and Rhodothermus obanensis. Extremophiles,1999,3:163-172. [4] Zhu D,Cui S.Isolation and characterization of salt-sensitive mutants of the moderately halophilic bacterium,Salinivibrio costicola subsp. Yaniac.Biosci Biochem,2008,72:1977-1982. [5] Fan T W.Metabolite profiling by one and two-dimensional NMR analysis of complex mixtures.Progr Nucl Magn Res Spec,1997,28:161-219. [6] 何建，汪婷，孙纪全等.以四氢嘧啶为主要相容性溶质的中毒嗜盐菌I15的分离特性研究.微生物学报，2005，45（6）:900-904 [7] Annelies E. Onraedt,Bart A.Walcarius et al .Optimization of Ectoine Synthesis through Fed-Batch Fermentation of Brevibacterium epidermis.Biotechnol Progr,2005(21):1206-1212 [8] 蔡谨，孙章辉，王隽等.补料发酵工艺的应用及其研究.工业微生物，2005，35（1）：42-48. [9] 邓开野，谭梅唇.分批发酵和补料分批发酵结合生产透明质酸的研究.食品工业科技,2011(1):166-168. [10] Thomas Sauer,Erwin A Galinski. Bacterial milking: a novel bioprocess for production of compatible solutes.Biotechnology and Bioengineering,1998,57(3):306-313. [11] Frings E,Sauer T,Galinski EA.Production of hydroxyectione:high cell density cultivation and osmotic down shock of Marinococcus strain M52.J Biotechnol,1995,61:117-158. [12] Ono H, Sawda K,Kbunajakr N,et al.Characterization of biosynthetic enzynes for ectione as a compatible solute in a moderately halophilic eubacterium, Halomonas elongata. J.Bacteriol,1999,181:91-99. [13] Hashimoto S,Ozaki A.Whole microbial cell proeesses for manufaacturing amino acids,vitamins or ribonucleotides[J].Current Opinion in Biotechnology,1999,10:604-608. [14] 易奎星，杨亚力，杨顺楷等.静息细胞连续两批次生物催化生产氢化可的松.生物加工过程,2005,3(4):40-44. [15] Ya-Jun Lang,Lin Bai,Ya-nan Ren,et al.Production of ectione through a combined process that uses both growing and resting cells of Halomonas salina DSM 5928T.Extrmophiles,2011,15:303-310. [16] Shinichi Nagata,Yaoqiang,Akinohu Oshima,et al.Efficient cyclic system to yield ection using Brevibacterium sp.JCM 6894 subjected toosmotic downshock.Bio-technology and bioengineering,2008,99(4):941-948.

3. 毕业设计（论文）进程安排

2017年12月-2018年1月：准备实验材料后开始实验；在高盐浓度条件下筛选中度嗜盐菌，并从得到的中度嗜盐菌中筛选四氢嘧啶生产菌 2018年3月：碳源和氮源种类筛选及浓度优化 2018年4月上旬：盐浓度及接种量优化 2018年4月中下旬：结束实验进程并撰写毕业论文