臺灣博碩士論文加值系統

本研究使用高解析力粒徑分析儀測定耐輻射奇異球菌菌液中細胞體積並以分佈曲線表示之。這些體積分佈曲線經過特定的數據處理後可得到許多明顯的高峰。體積高峰的出現提供了數字化的細胞體積分佈狀態，因而易於觀察比較樣本之間的差異。例如，以上述方法比較耐輻射奇異球菌野生型菌株與生長速度較慢的突變株的不同，發現突變株生長緩慢似乎與其具有顯著較長的 D 期（相當於真核細胞的 G2/M 期）有關。此較長的 D 期反映在較多數量的體積高峰上。
這樣的初步結果暗示，體積分佈曲線中體積高峰反映奇異球菌細胞生長時體積的增大是受到嚴格控制的。為進一步瞭解此種體積增大控制現象的本質，我們對二十八個耐輻射奇異球菌培養菌液進行觀測，進行數據處理後，得到高出現頻率體積（FOVs, frequently occurring volumes）的出現頻率圖。體積峰出現頻率呈現兩個出現頻率較高的體積區間。配合細胞族群的體積分佈狀態，與細胞週期的概念，可以概略的分辨細胞週期對應的體積峰。改變生長條件對於細胞的影響，也可以由體積峰的變化輕易的觀察之。

Abstract
Sizes of individual cells in a Deinococcus radiodurans IR culture were measured by a Coulter size analyzer, and the resulted cell-particle-size distribution curves was found to display obvious peaks. A data modification system was used to render these peaks more distinguishable but at the same time causing no alternations in the basic traits of the distribution curve. The distinguishable peaks defined volumes as numeric (quantificational) data, thus help comparison study. For example, by using this size-distribution-data-processing approach, we were able to conclude that in comparison with its wild-type strain (IR), a slow-growing mutant strain (X2) was defective in the cell separation stages producing a much longer D phase. The results suggest that cell size increase in D. radiodurans was in tight control. Twenty-eight D. radiodurans IR cultures were similarly assayed and data modification system was used. Pooled results showed frequently occurring volumes (FOVs). Some FOVs constitute high-frequency regions in the cell size distribution curves. Based in the results, the pattern of the distinguishable peaks appears to be useful in studying cell growth physiology. The defined FOVs are suggestive of a tight cell-size control during the growth of a bacterial cell. In summary, cell-size increase during bacterial growth appears to be discontinuous in a stepwise fashion.

1. 中文摘要.....................................................-1-
2. 英文摘要.....................................................-2-
3. 簡介.........................................................-3-
4. 材料與方法...................................................-5-
5. 結果........................................................-10-
6. 討論........................................................-18-
7. 參考文獻....................................................-23-
8. 圖表..........................................................i

Nurse, P. 2000. A long twentieth century of the cell cycle and beyond. Cell. 100:71-78.
Botello, E., and K. Nordström. 1998. Effects of chromosome underreplication on cell division in Escherichia coli. Journal of Bacteriology. 180:6364-6374.
Mattias Jansson, B. P., L. Malandrin, and H. E. Johansson. 2000. Cell cycle arrest in archaea by hypusination inhibitor N1-Guanyl-1,7-Diaminoheptane. Journal of Bacteriology. 182:1158-1161.
HAHN, W. H., and M. G. Höfle. 1999. Flagellate prediation on a bacterial model community interplay of size-selective garzing, specific bacterial cell size, and bacterial community composition. Applied and Environmental Microbiology. 65:4863-4872.
Artsimovitch, I., and R. Landick. 2000. Pausing by bacterial RNA polymerase is mediated by mechanistically distinct classes of signals. Proceedings of the National Academy of Sciences of the United States of America. 97:7090-7095.
Ohta, N., M. Masurekar, and A. Newton. 1990. Cloning and cell cycle-dependent expression of DNA replication gene dnaC from Caulobacter crescentus. Journal of Bacteriology. 172:7027-7034.
John, P. C. 1984. Control of the cell division cycle in Chlamydomonas. Microbiological Sciences. 1:96-101.
Knacker, T., J. L. Harwood, C.N. Hunter., and N. J. Russell. 1985. Lipid biosynthesis in synchronized cultures of the photosynthetic bacterium Rhodopseudomonas sphaeroides. Biochemical Journal. 229:701-710.
Kern, P., L. Keilholz, C. Forster, M. H. Seegenschmiedt, R. Sauer, and M. Herrmann. 1999. In vitro apoptosis in peripheral blood mononuclear cells induced by low-dose radiotherapy displays a discontinuous dose-dependence. International Journal of Radiation Biology. 75:995-1003.
Bridges, B. A. 1995. Are there DNA damage checkpoints in E. coli? Bioessays. 17:63-70.
Grover, N. B., and C. L. Woldringh. 2001. Dimensional regulation of cell-cycle events in Escherichia coli during steady-state growth. Microbiology. 147:171-181.
Thornton, M., K. L. Eward, C. E. Helmstetter. 2002. Production of minimally
disturbed synchronous cultures of hematopoietic cells. Biotechniques. 32:1098-1105.
Ian, W., P. Frank, L. David, J. Robert, I. Critchley, M. Newman, J. Warrack, T. Giokarini, A. J. Hayes, P. F. Randerson, and W. A. Venables. 1999. Flow cytometry and other techniques show that Staphylococcus aureus undergoes significant physiological changes in the early stages of surface-attached culture. Microbiology. 145:1325—1333.
Buddelmeijer, N., M. E. G. Aarsman, A. H. J. Kolk, M. Vicente, and N. Nanninga. 1998. Localization of cell division protein FtsQ by immunofluorescence microscopy in dividing and nondividing Cells of Escherichia coli. Journal of Bacteriology. 180:6107-6116.
Marie, D., F. Partensky, S. Jacquet, and D. Vaulot. 1996. Enumeration and cell cycle analysis of natural populations of marine Picoplankton by flow cytometry using the nucleic acid stain SYBR Green I. Applied and Environmental Microbiology. 63:186-193.
Anderson, K. R., N. H. Mendelson, and J. C. Watkinsa. 2000. A new mathematical approach predicts individual cell growth behavior using bacterial population information. J. theor. Biol. 202:87-94.
Ramsing, N. B., H. Fossing, T. G. Ferdelman, F. Andersen., and B. Thamdrup. 1996. Distribution of bacterial populations in a stratified fjord (Mariager Fjord, Denmark) quantified by in situ hybridization and related to chemical gradients in the water column. Applied & Environmental Microbiology. 62:1391-1404.
Hoet, P. P., M. M. Coene., and C. G. Cocito. 1992. Replication cycle of Bacillus subtilis hydroxymethyluracil-containing phages. Annual Review of Microbiology. 46:95-116.
Galloway, S. M., J. E. Miller, M. J. Armstrong, C. L. Bean, T. R. Skopek, and W. W. Nichols. 1998. DNA synthesis inhibition as an indirect mechanism of chromosome aberrations: comparison of DNA-reactive and non-DNA-reactive clastogens. Mutation Research. 400:169-186.
Kron, S. J., C. A. Styles, and G. R. Fink. 1994. Symmetric cell division in pseudohyphae of the yeast Saccharomyces cerevisiae. Molecular Biology of the Cell. 5:1003-1022.
Dien, B. S., and F. Srienc. 1991. Bromodeoxyuridine labeling and flow cytometric identification of replicating Saccharomyces cerevisiae cells: lengths of cell cycle phases and population variability at specific cell cycle positions. Biotechnology Progress. 7:291-298.
Calvert, G. R., and I. W. Dawes. 1984. Cell size control of development in Saccharomyces cerevisiae. Nature. 312:61-63.
Johnston, G. C., C. W. Ehrhardt, A. Lorincz., and B. L. Carter. 1979. Regulation of cell size in the yeast Saccharomyces cerevisiae. Journal of Bacteriology. 137:1-5.
Hartwell, L. H., and M. W. Unger. 1977. Unequal division in Saccharomyces cerevisiae and its implications for the control of cell division. Journal of Cell Biology. 75:422-435.
Sokol, M. 2001. Analysis of in vivo 1H MR spectra of normal brain tissue by means of second derivative method. Medical Science Monitor. 7:496-503.
Button, D. K., and B. R. Robertson. 2001. Determination of DNA content of aquatic bacteria by flow cytometry. Applied and Environmental Microbiology. 67:1636-1645.