臺灣博碩士論文加值系統

數量感應系統為細菌的一套二元系統 (two-component system)，是細菌與細菌之間溝通的方式。細菌利用產生和偵測一種稱為自體誘導物(autoinducer, AI)的化學分子，來監測細胞密度並藉此集體控制基因的表現。LuxS (S-ribosylhomocysteine lyase)廣泛的存在於細菌中，是合成AI-2的酵素。許多研究指出LuxS/AI-2系統廣泛存在於細菌中，影響細菌的生理行為與毒性功能。為了瞭解LuxS在食品病原菌腸炎弧菌中所扮演的角色，我們使用一株不帶有tdh基因與trh基因的野生株VP93，建構了一株luxS突變株。利用V. harveyi 冷光表現分析，發現野生株在生長穩定期有較高的冷光表現量。如同預期的，突變掉luxS基因會破壞腸炎弧菌AI-2的產生。除此之外，野生株和突變株在蛋白酶的分泌、細菌的爬行能力和菌落外觀的觀察中並無顯著差異。然而與野生株相比，luxS突變株的生物膜生成量顯著降低，且泳動能力明顯增加。我們利用二維蛋白質體方法比較野生株與突變株的蛋白質表現，在胞內蛋白質體(intracellular proteomes)分析中，與反應壓力環境有關的蛋白質(GroEL)和與細胞分裂相關的蛋白質(FtsZ)只在野生株中被偵測到。相反的，細胞外膜蛋白OmpA和OmpU卻只出現在突變株中。同樣的，參與胺基酸與嘌呤生合成相關的酵素蛋白質在luxS突變株中高度表現。胞外蛋白質體(extracellular proteomes)的分析結果中，我們發現外膜蛋白(OmpU)和外膜通道蛋白(TolC)只在野生株中表現，但端鞭毛蛋白(FlaA)卻在突變株中表現較明顯。此外，我們亦分析了一些目前被認為可能與腸炎弧菌毒力相關的基因，並利用RT-PCR的方式比較在野生株與突變株的基因表現量。結果顯示突變luxS基因會使得莢膜多醣類基因(cpsA)的表現量下降，但卻使得鞭毛基因(flaA)的表現量上升。根據本研究的結果可知，突變luxS基因會影響細菌的生物膜生成量和泳動能力，同時，藉由蛋白質體方法，我們也在腸炎弧菌中找到許多受LuxS調控的基因。

Quorum sensing system, a two-component system in bacteria, is a cell-cell communication process. Bacteria use the production and detection of the extracellular chemical signals called autoinducers (AI) to monitor cell density and coordinate gene expression. The LuxS enzyme (S-ribosylhomocysteinlyase), which is conserved in a wide variety of bacteria, is responsible for the production of autoinduer-2 (AI-2). It has been reported that LuxS/AI-2 system has multiple roles in interfering with physiological and virulence functions in many bacteria. To gain insight into LuxS function in seafood-borne pathogen Vibrio parahaemolyticus, we have constructed and characterized a luxS mutant in the tdh-and trh-negative strain named VP93. Using the V. harveyi bioassay, the highest level of AI-2 was detected in the supernatant of stationary-phase cells of wild type. As expected, mutation of luxS abolished their AI-2 production. Besides, protease secretion, swarming activity and colony morphology showed no significant difference between the wild type and its mutant. However, it was found that biofilm formation was diminished but swimming motility was increased in the luxS mutant. The global protein expression profiles of the wild type and the mutant were also compared by 2D proteome analysis. In the analysis of intracellular proteomes, proteins generated under stress conditions (GroEL) and proteins involved in cell division (FtsZ) were detected in wild type. In contrast, cell envelope proteins, OmpA and OmpU, were abundant in the luxS mutant. Additionally, enzymes involved in amino acid synthesis and purine ribonucleotide synthesis were also increased in the mutant strain. In extracellular proteome analysis, outer membrane protein (OmpU) and outer membrane channel protein (TolC) were only abundant in the wild type, but the polar flagellin protein (FlaA) was detected in the luxS mutant. Finally, we also examined the reported virulence factor genes in V. parahaemolyticus in the wild type and its mutant by RT-PCR. The result showed that mutation of luxS resulted in down-regulation of capsular polysaccharide gene (cpsA) expression and up-regulation of flagella gene (flaA) expression. In conclusion, mutation of luxS in VP93 might influence biofilm formation and swimming motility. Besides, several LuxS-regulated genes were also found in this study.

中文摘要 i
英文摘要 ii
壹、前言 1
一、 腸炎弧菌簡介 1
二、 細菌的數量感應 2
三、 LuxS/AI-2系統的研究 4
四、 研究目的與架構 4
貳、材料與方法 6
一、實驗材料 6
1. 菌株、質體與引子 6
2. 培養基與試藥 6
3. 儀器設備 6
二、實驗方法 7
1. 培養基的配製 7
2. 細菌染色體DNA之萃取 9
3. 聚合酶連鎖反應 (Polymerase chain reaction, PCR) 9
4. 利用overlap PCR製備腸炎弧菌luxS突變片段 10
5. 建構腸炎弧菌luxS互補質體 10
6. DNA片段切割 11
7. TA cloning 11
8. DNA接合反應 (Ligation) 11
9. 大腸桿菌勝任細胞 (Competent cell)製備方法 11
10. 細胞熱休克轉型作用 12
11. 細菌接合生殖 (Conjugation) 12
12. AI-2 分析 12
13. 生長曲線之測定 13
14. 序列稀釋點盤法 (Drop count method) 13
15. 生物膜之測定 13
16. 生物膜之定量分析 13
17. 掃描式電子顯微鏡樣品製備 14
18. 穿透式電子顯微鏡樣本製備 14
19. 蛋白酶活性測試 14
20. 蛋白酶活性膠體電泳 (zymogram) 15
21. 溶血活性測試 15
22. 胞內蛋白質萃取 16
23. 胞外蛋白質萃取 16
24. 蛋白質定量 16
25. 二維電泳 (Two-dimensional gel electrophoresis, 2-DE)分析 17
26. 二維電泳膠掃描 (Scanning)及影像比對 (Image analysis) 18
27. 膠內酵素水解 (In-gel digestion) 18
28. MALDI-TOF 質譜儀分析 19
29. 蛋白質質譜鑑定與資料庫搜尋 20
30. 細菌RNA之萃取 20
31. 互補DNA (Complement DNA, cDNA)之合成 21
參、結果 22
一、腸炎弧菌luxS之序列分析 22
二、 腸炎弧菌luxS相關重組菌株之建構 23
1. 建構luxS突變株 23
2. 建構luxS互補菌株 23
三、 luxS突變株的鑑定 24
1. 以PCR方法檢測luxS突變株與luxS互補菌株 24
2. 冷光表現量分析 24
四、比較luxS突變株與野生株的表現型(phenotype)差異 24
1. 生長曲線 24
2. 菌落型態之觀察 25
3. 游動與爬行能力 25
4. 生物膜生成量分析 25
5. 細菌外觀之觀察 26
6. 蛋白酶活性測試 27
7. 溶血活性測試 27
五、LuxS可能影響的壓力反應 28
1. 酸處理下的存活情形 28
2. 膽鹽培養下的存活情形 28
六、比較luxS突變株與野生株的蛋白質體差異 28
1. 胞內蛋白質體之分析 28
2. 胞外蛋白質體之分析 29
七、LuxS對腸炎弧菌毒力基因表現的影響 30
1. 確認相關的毒力基因是否存在於腸炎弧菌VP93 31
2. 腸炎弧菌相關的毒力基因在luxS突變株與野生株的表現情形 31
肆、討論 32
一、突變luxS對腸炎弧菌表現型之影響 32
二、LuxS在腸炎弧菌遭受環境壓力時所扮演的角色 33
三、以蛋白質體差異探討受LuxS所影響的基因 34
四、LuxS影響毒力基因之表現情形 35
五、腸炎弧菌中的AI-2/LuxS系統 37
參考文獻 38

1.Aharoni, R., M. Bronstheyn, A. Jabbour, B. Zaks, M. Srebnik, and D. Steinberg. 2008. Oxazaborolidine derivatives inducing autoinducer-2 signal transduction in Vibrio harveyi. Bioorg Med Chem 16:1596-1604.
2.Ahmed, N. A., F. C. Petersen, and A. A. Scheie. 2009. AI-2/LuxS is involved in increased biofilm formation by Streptococcus intermedius in the presence of antibiotics. Antimicrob Agents Chemother 53:4258-4263.
3.Balestrino, D., J. A. Haagensen, C. Rich, and C. Forestier. 2005. Characterization of type 2 quorum sensing in Klebsiella pneumoniae and relationship with biofilm formation. J Bacteriol 187:2870-2880.
4.Bassler, B. L. 2002. Small talk. Cell-to-cell communication in bacteria. Cell 109:421-424.
5.Bassler, B. L., M. Wright, R. E. Showalter, and M. R. Silverman. 1993. Intercellular signalling in Vibrio harveyi: sequence and function of genes regulating expression of luminescence. Mol Microbiol 9:773-786.
6.Brackman, G., S. Celen, K. Baruah, P. Bossier, S. Van Calenbergh, H. J. Nelis, and T. Coenye. 2009. AI-2 quorum-sensing inhibitors affect the starvation response and reduce virulence in several Vibrio species, most likely by interfering with LuxPQ. Microbiology 155:4114-4122.
7.Brackman, G., S. Celen, U. Hillaert, S. Van Calenbergh, P. Cos, L. Maes, H. J. Nelis, and T. Coenye. 2011. Structure-activity relationship of cinnamaldehyde analogs as inhibitors of AI-2 based quorum sensing and their effect on virulence of Vibrio spp. PLoS One 6:e16084.
8.Bradford, M. M. 1976. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem 72:248-254.
9.Broberg, C. A., L. Zhang, H. Gonzalez, M. A. Laskowski-Arce, and K. Orth. 2010. A Vibrio effector protein is an inositol phosphatase and disrupts host cell membrane integrity. Science 329:1660-1662.
10.Bumann, D., S. Aksu, M. Wendland, K. Janek, U. Zimny-Arndt, N. Sabarth, T. F. Meyer, and P. R. Jungblut. 2002. Proteome analysis of secreted proteins of the gastric pathogen Helicobacter pylori. Infect Immun 70:3396-3403.
11.Caburlotto, G., M. Gennari, V. Ghidini, M. Tafi, and M. M. Lleo. 2009. Presence of T3SS2 and other virulence-related genes in tdh-negative Vibrio parahaemolyticus environmental strains isolated from marine samples in the area of the Venetian Lagoon, Italy. FEMS Microbiol Ecol 70:506-514.
12.Cherwonogrodzky, J. W., and A. G. Clark. 1981. Effect of pH on the production of the Kanagawa hemolysin by Vibrio parahaemolyticus. Infect Immun 34:115-119.
13.de Kievit, T. R., and B. H. Iglewski. 2000. Bacterial quorum sensing in pathogenic relationships. Infect Immun 68:4839-4849.
14.DebRoy, S., J. Dao, M. Soderberg, O. Rossier, and N. P. Cianciotto. 2006. Legionella pneumophila type II secretome reveals unique exoproteins and a chitinase that promotes bacterial persistence in the lung. Proc Natl Acad Sci U S A 103:19146-19151.
15.DeLisa, M. P., C. F. Wu, L. Wang, J. J. Valdes, and W. E. Bentley. 2001. DNA microarray-based identification of genes controlled by autoinducer 2-stimulated quorum sensing in Escherichia coli. J Bacteriol 183:5239-5247.
16.Doherty, N. C., F. Shen, N. M. Halliday, D. A. Barrett, K. R. Hardie, K. Winzer, and J. C. Atherton. 2010. In Helicobacter pylori, LuxS is a key enzyme in cysteine provision through a reverse transsulfuration pathway. J Bacteriol 192:1184-1192.
17.Donnenberg, M. S., and J. B. Kaper. 1991. Construction of an eae deletion mutant of enteropathogenic Escherichia coli by using a positive-selection suicide vector. Infect Immun 59:4310-4317.
18.Dunn, A. K., D. S. Millikan, D. M. Adin, J. L. Bose, and E. V. Stabb. 2006. New rfp- and pES213-derived tools for analyzing symbiotic Vibrio fischeri reveal patterns of infection and lux expression in situ. Appl Environ Microbiol 72:802-810.
19.Dunne, W. M., Jr. 2002. Bacterial adhesion: seen any good biofilms lately? Clin Microbiol Rev 15:155-166.
20.Eboigbodin, K. E., J. R. Newton, A. F. Routh, and C. A. Biggs. 2006. Bacterial quorum sensing and cell surface electrokinetic properties. Appl Microbiol Biotechnol 73:669-675.
21.Ellis, T. N., and M. J. Kuehn. 2010. Virulence and immunomodulatory roles of bacterial outer membrane vesicles. Microbiol Mol Biol Rev 74:81-94.
22.Engebrecht, J., and M. Silverman. 1984. Identification of genes and gene products necessary for bacterial bioluminescence. Proc Natl Acad Sci U S A 81:4154-4158.
23.Enos-Berlage, J. L., Z. T. Guvener, C. E. Keenan, and L. L. McCarter. 2005. Genetic determinants of biofilm development of opaque and translucent Vibrio parahaemolyticus. Mol Microbiol 55:1160-1182.
24.Federle, M. J., and B. L. Bassler. 2003. Interspecies communication in bacteria. J Clin Invest 112:1291-1299.
25.Freeman, J. A., B. N. Lilley, and B. L. Bassler. 2000. A genetic analysis of the functions of LuxN: a two-component hybrid sensor kinase that regulates quorum sensing in Vibrio harveyi. Mol Microbiol 35:139-149.
26.Guvener, Z. T., and L. L. McCarter. 2003. Multiple regulators control capsular polysaccharide production in Vibrio parahaemolyticus. J Bacteriol 185:5431-5441.
27.Hammer, B. K., and B. L. Bassler. 2009. Distinct sensory pathways in Vibrio cholerae El Tor and classical biotypes modulate cyclic dimeric GMP levels to control biofilm formation. J Bacteriol 191:169-177.
28.Hammer, B. K., and B. L. Bassler. 2003. Quorum sensing controls biofilm formation in Vibrio cholerae. Mol Microbiol 50:101-104.
29.Hanahan, D. 1983. Studies on transformation of Escherichia coli with plasmids. J Mol Biol 166:557-580.
30.Henke, J. M., and B. L. Bassler. 2004. Quorum sensing regulates type III secretion in Vibrio harveyi and Vibrio parahaemolyticus. J Bacteriol 186:3794-3805.
31.Heussen, C., and E. B. Dowdle. 1980. Electrophoretic analysis of plasminogen activators in polyacrylamide gels containing sodium dodecyl sulfate and copolymerized substrates. Anal Biochem 102:196-202.
32.Hiyoshi, H., T. Kodama, T. Iida, and T. Honda. 2010. Contribution of Vibrio parahaemolyticus virulence factors to cytotoxicity, enterotoxicity, and lethality in mice. Infect Immun 78:1772-1780.
33.Honda, T., Y. X. Ni, and T. Miwatani. 1988. Purification and characterization of a hemolysin produced by a clinical isolate of Kanagawa phenomenon-negative Vibrio parahaemolyticus and related to the thermostable direct hemolysin. Infect Immun 56:961-965.
34.Iida-Hasegawa, N., A. Furuhata, H. Hayatsu, A. Murakami, K. Fujiki, K. Nakayasu, and A. Kanai. 2003. Mutations in the CHST6 gene in patients with macular corneal dystrophy: immunohistochemical evidence of heterogeneity. Invest Ophthalmol Vis Sci 44:3272-3277.
35.James, B. W., W. S. Mauchline, R. B. Fitzgeorge, P. J. Dennis, and C. W. Keevil. 1995. Influence of iron-limited continuous culture on physiology and virulence of Legionella pneumophila. Infect Immun 63:4224-4230.
36.Joseph, S. W., R. R. Colwell, and J. B. Kaper. 1982. Vibrio parahaemolyticus and related halophilic Vibrios. Crit Rev Microbiol 10:77-124.
37.Kaysner, C. A. 1981. Incidence of Vibrio alginolyticus and bacteria of sanitary significance in the Bering Sea. Appl Environ Microbiol 41:1279-1282.
38.Kaysner, C. A., C. Abeyta, Jr., P. A. Trost, J. H. Wetherington, K. C. Jinneman, W. E. Hill, and M. M. Wekell. 1994. Urea hydrolysis can predict the potential pathogenicity of Vibrio parahaemolyticus strains isolated in the Pacific Northwest. Appl Environ Microbiol 60:3020-3022.
39.Kierek, K., and P. I. Watnick. 2003. Environmental determinants of Vibrio cholerae biofilm development. Appl Environ Microbiol 69:5079-5088.
40.Kim, S. Y., S. E. Lee, Y. R. Kim, C. M. Kim, P. Y. Ryu, H. E. Choy, S. S. Chung, and J. H. Rhee. 2003. Regulation of Vibrio vulnificus virulence by the LuxS quorum-sensing system. Mol Microbiol 48:1647-1664.
41.Kim, Y. K., and L. L. McCarter. 2000. Analysis of the polar flagellar gene system of Vibrio parahaemolyticus. J Bacteriol 182:3693-3704.
42.Kim, Y. K., and L. L. McCarter. 2007. ScrG, a GGDEF-EAL protein, participates in regulating swarming and sticking in Vibrio parahaemolyticus. J Bacteriol 189:4094-4107.
43.Klose, K. E., V. Novik, and J. J. Mekalanos. 1998. Identification of multiple sigma54-dependent transcriptional activators in Vibrio cholerae. J Bacteriol 180:5256-5259.
44.Kovacikova, G., W. Lin, and K. Skorupski. 2010. The LysR-type virulence activator AphB regulates the expression of genes in Vibrio cholerae in response to low pH and anaerobiosis. J Bacteriol 192:4181-4191.
45.Krasilnikov, O. V., J. N. Muratkhodjaev, and A. O. Zitzer. 1992. The mode of action of Vibrio cholerae cytolysin. The influences on both erythrocytes and planar lipid bilayers. Biochim Biophys Acta 1111:7-16.
46.Lantz, M. S., and P. Ciborowski. 1994. Zymographic techniques for detection and characterization of microbial proteases. Methods Enzymol 235:563-594.
47.Lee, A. S., and K. P. Song. 2005. LuxS/autoinducer-2 quorum sensing molecule regulates transcriptional virulence gene expression in Clostridium difficile. Biochem Biophys Res Commun 335:659-666.
48.Lee, C. Y., S. F. Pan, and C. H. Chen. 1995. Sequence of a cloned pR72H fragment and its use for detection of Vibrio parahaemolyticus in shellfish with the PCR. Appl Environ Microbiol 61:1311-1317.
49.Lee, C. Y., S. C. Su, and R. B. Liaw. 1995. Molecular analysis of an extracellular protease gene from Vibrio parahaemolyticus. Microbiology 141 ( Pt 10):2569-2576.
50.Li, L., Z. Xu, Y. Zhou, T. Li, L. Sun, H. Chen, and R. Zhou. 2011. Analysis on Actinobacillus pleuropneumoniae LuxS regulated genes reveals pleiotropic roles of LuxS/AI-2 on biofilm formation, adhesion ability and iron metabolism. Microb Pathog 50:293-302.
51.Lilley, B. N., and B. L. Bassler. 2000. Regulation of quorum sensing in Vibrio harveyi by LuxO and sigma-54. Mol Microbiol 36:940-954.
52.Lin, J., S. Huang, and Q. Zhang. 2002. Outer membrane proteins: key players for bacterial adaptation in host niches. Microbes Infect 4:325-331.
53.Lin, J. F. 1988. Effect of pH, NaCl, temperature and time of incubation on the probability of Vibrio parahaemolyticus growth initiation in a model broth. Acta Vet Scand Suppl 84:283-286.
54.Ling, H., A. Kang, M. H. Tan, X. Qi, and M. W. Chang. 2010. The absence of the luxS gene increases swimming motility and flagella synthesis in Escherichia coli K12. Biochem Biophys Res Commun 401:521-526.
55.Loh, J. T., M. H. Forsyth, and T. L. Cover. 2004. Growth phase regulation of flaA expression in Helicobacter pylori is luxS dependent. Infect Immun 72:5506-5510.
56.Lyon, W. R., J. C. Madden, J. C. Levin, J. L. Stein, and M. G. Caparon. 2001. Mutation of luxS affects growth and virulence factor expression in Streptococcus pyogenes. Mol Microbiol 42:145-157.
57.Matz, C., D. McDougald, A. M. Moreno, P. Y. Yung, F. H. Yildiz, and S. Kjelleberg. 2005. Biofilm formation and phenotypic variation enhance predation-driven persistence of Vibrio cholerae. Proc Natl Acad Sci U S A 102:16819-16824.
58.McCarter, L. L. 1998. OpaR, a homolog of Vibrio harveyi LuxR, controls opacity of Vibrio parahaemolyticus. J Bacteriol 180:3166-3173.
59.McIver, K. S., A. S. Heath, and J. R. Scott. 1995. Regulation of virulence by environmental signals in group A streptococci: influence of osmolarity, temperature, gas exchange, and iron limitation on emm transcription. Infect Immun 63:4540-4542.
60.Merritt, J., F. Qi, S. D. Goodman, M. H. Anderson, and W. Shi. 2003. Mutation of luxS affects biofilm formation in Streptococcus mutans. Infect Immun 71:1972-1979.
61.Miller, M. B., and B. L. Bassler. 2001. Quorum sensing in bacteria. Annu Rev Microbiol 55:165-199.
62.Miyamoto, Y., Y. Obara, T. Nikkawa, S. Yamai, T. Kato, Y. Yamada, and M. Ohashi. 1980. Simplified purification and biophysicochemical characteristics of Kanagawa phenomenon-associated hemolysin of Vibrio parahaemolyticus. Infect Immun 28:567-576.
63.Moslehi-Jenabian, S., K. Gori, and L. Jespersen. 2009. AI-2 signalling is induced by acidic shock in probiotic strains of Lactobacillus spp. Int J Food Microbiol 135:295-302.
64.Nagayama, K., T. Oguchi, M. Arita, and T. Honda. 1995. Purification and characterization of a cell-associated hemagglutinin of Vibrio parahaemolyticus. Infect Immun 63:1987-1992.
65.Nakano, M., A. Takahashi, Z. Su, N. Harada, K. Mawatari, and Y. Nakaya. 2008. Hfq regulates the expression of the thermostable direct hemolysin gene in Vibrio parahaemolyticus. BMC Microbiol 8:155.
66.Ng, W. L., and B. L. Bassler. 2009. Bacterial quorum-sensing network architectures. Annu Rev Genet 43:197-222.
67.O'Toole, G. A., L. A. Pratt, P. I. Watnick, D. K. Newman, V. B. Weaver, and R. Kolter. 1999. Genetic approaches to study of biofilms. Methods Enzymol 310:91-109.
68.Park, K. S., T. Ono, M. Rokuda, M. H. Jang, K. Okada, T. Iida, and T. Honda. 2004. Functional characterization of two type III secretion systems of Vibrio parahaemolyticus. Infect Immun 72:6659-6665.
69.Philippe, N., J. P. Alcaraz, E. Coursange, J. Geiselmann, and D. Schneider. 2004. Improvement of pCVD442, a suicide plasmid for gene allele exchange in bacteria. Plasmid 51:246-255.
70.Rader, B. A., S. R. Campagna, M. F. Semmelhack, B. L. Bassler, and K. Guillemin. 2007. The quorum-sensing molecule autoinducer 2 regulates motility and flagellar morphogenesis in Helicobacter pylori. J Bacteriol 189:6109-6117.
71.Raimondi, F., J. P. Kao, C. Fiorentini, A. Fabbri, G. Donelli, N. Gasparini, A. Rubino, and A. Fasano. 2000. Enterotoxicity and cytotoxicity of Vibrio parahaemolyticus thermostable direct hemolysin in in vitro systems. Infect Immun 68:3180-3185.
72.Ruby, E. G., and M. J. McFall-Ngai. 1992. A squid that glows in the night: development of an animal-bacterial mutualism. J Bacteriol 174:4865-4870.
73.Sarkar, B. L., R. Kumar, S. P. De, and S. C. Pal. 1987. Hemolytic activity of and lethal toxin production by environmental strains of Vibrio parahaemolyticus. Appl Environ Microbiol 53:2696-2698.
74.Shime-Hattori, A., T. Iida, M. Arita, K. S. Park, T. Kodama, and T. Honda. 2006. Two type IV pili of Vibrio parahaemolyticus play different roles in biofilm formation. FEMS Microbiol Lett 264:89-97.
75.Shimohata, T., and A. Takahashi. 2010. Diarrhea induced by infection of Vibrio parahaemolyticus. J Med Invest 57:179-182.
76.Sikora, A. E., R. A. Zielke, D. A. Lawrence, P. C. Andrews, and M. Sandkvist. 2011. Proteomic analysis of the Vibrio cholerae type II secretome reveals new proteins, including three related serine proteases. J Biol Chem 286:16555-16566.
77.Soni, K. A., L. Lu, P. R. Jesudhasan, M. E. Hume, and S. D. Pillai. 2008. Influence of autoinducer-2 (AI-2) and beef sample extracts on E. coli O157:H7 survival and gene expression of virulence genes yadK and hhA. J Food Sci 73:M135-139.
78.Sperandio, V., A. G. Torres, J. A. Giron, and J. B. Kaper. 2001. Quorum sensing is a global regulatory mechanism in enterohemorrhagic Escherichia coli O157:H7. J Bacteriol 183:5187-5197.
79.Stewart, B. J., and L. L. McCarter. 2003. Lateral flagellar gene system of Vibrio parahaemolyticus. J Bacteriol 185:4508-4518.
80.Su, Z., M. Nakano, T. Koga, X. Lian, A. Hamamoto, T. Shimohata, Y. Harada, K. Mawatari, N. Harada, M. Akutagawa, Y. Nakaya, and A. Takahashi. 2010. Hfq regulates anti-oxidative ability in Vibrio parahaemolyticus. J Gen Appl Microbiol 56:181-186.
81.Takeda, Y., T. Honda, H. Sima, T. Tsuji, and T. Miwatani. 1983. Analysis of antigenic determinants in cholera enterotoxin and heat-labile enterotoxins from human and porcine enterotoxigenic Escherichia coli. Infect Immun 41:50-53.
82.Tsao, C. Y., L. Wang, Y. Hashimoto, H. Yi, J. C. March, M. P. DeLisa, T. K. Wood, J. J. Valdes, and W. E. Bentley. 2011. LuxS coexpression enhances yields of recombinant proteins in Escherichia coli in part through posttranscriptional control of GroEL. Appl Environ Microbiol 77:2141-2152.
83.Udekwu, K. I. 2010. Transcriptional and post-transcriptional regulation of the Escherichia coli luxS mRNA; involvement of the sRNA MicA. PLoS One 5:e13449.
84.Udekwu, K. I., F. Darfeuille, J. Vogel, J. Reimegard, E. Holmqvist, and E. G. Wagner. 2005. Hfq-dependent regulation of OmpA synthesis is mediated by an antisense RNA. Genes Dev 19:2355-2366.
85.Wen, Z. T., and R. A. Burne. 2004. LuxS-mediated signaling in Streptococcus mutans is involved in regulation of acid and oxidative stress tolerance and biofilm formation. J Bacteriol 186:2682-2691.
86.Weng, J. H., H. C. Wong, C. C. Liu, S. Y. Lee, C. M. Yu, Y. S. Lee, H. C. Tseng, and K. Y. Lu. 1995. Characterization of the manganese-resistant mutants derived from Vibrio parahaemolyticus. Zhonghua Min Guo Wei Sheng Wu Ji Mian Yi Xue Za Zhi 28:256-269.
87.Widmer, K. W., P. R. Jesudhasan, S. E. Dowd, and S. D. Pillai. 2007. Differential expression of virulence-related genes in A Salmonella enterica serotype typhimurium luxS mutant in response to autoinducer AI-2 and poultry meat-derived AI-2 inhibitor. Foodborne Pathog Dis 4:5-15.
88.Wong, H. C., C. C. Liu, C. M. Yu, and Y. S. Lee. 1996. Utilization of iron sources and its possible roles in the pathogenesis of Vibrio parahaemolyticus. Microbiol Immunol 40:791-798.
89.Xavier, K. B., and B. L. Bassler. 2005. Regulation of uptake and processing of the quorum-sensing autoinducer AI-2 in Escherichia coli. J Bacteriol 187:238-248.
90.Xicohtencatl-Cortes, J., S. Lyons, A. P. Chaparro, D. R. Hernandez, Z. Saldana, M. A. Ledesma, M. A. Rendon, A. T. Gewirtz, K. E. Klose, and J. A. Giron. 2006. Identification of proinflammatory flagellin proteins in supernatants of Vibrio cholerae O1 by proteomics analysis. Mol Cell Proteomics 5:2374-2383.
91.Xu, L., H. Li, C. Vuong, V. Vadyvaloo, J. Wang, Y. Yao, M. Otto, and Q. Gao. 2006. Role of the luxS quorum-sensing system in biofilm formation and virulence of Staphylococcus epidermidis. Infect Immun 74:488-496.
92.Ye, J., Y. Ma, Q. Liu, D. L. Zhao, Q. Y. Wang, and Y. X. Zhang. 2008. Regulation of Vibrio alginolyticus virulence by the LuxS quorum-sensing system. J Fish Dis 31:161-169.
93.Yin, X., J. Zhu, Y. Feng, J. R. Chambers, J. Gong, and C. L. Gyles. 2011. Differential gene expression and adherence of Escherichia coli O157:H7 in vitro and in ligated pig intestines. PLoS One 6:e17424.
94.Yoshida, A., T. Ansai, T. Takehara, and H. K. Kuramitsu. 2005. LuxS-based signaling affects Streptococcus mutans biofilm formation. Appl Environ Microbiol 71:2372-2380.
95.Yuan, L., J. D. Hillman, and A. Progulske-Fox. 2005. Microarray analysis of quorum-sensing-regulated genes in Porphyromonas gingivalis. Infect Immun 73:4146-4154.
96.Zhao, L., T. Xue, F. Shang, H. Sun, and B. Sun. 2010. Staphylococcus aureus AI-2 quorum sensing associates with the KdpDE two-component system to regulate capsular polysaccharide synthesis and virulence. Infect Immun 78:3506-3515.
97.Zheng, J., O. S. Shin, D. E. Cameron, and J. J. Mekalanos. 2010. Quorum sensing and a global regulator TsrA control expression of type VI secretion and virulence in Vibrio cholerae. Proc Natl Acad Sci U S A 107:21128-21133.
98.Zhou, X., M. E. Konkel, and D. R. Call. 2010. Vp1659 is a Vibrio parahaemolyticus type III secretion system 1 protein that contributes to translocation of effector proteins needed to induce cytolysis, autophagy, and disruption of actin structure in HeLa cells. J Bacteriol 192:3491-3502.
99.Zhu, J., and J. J. Mekalanos. 2003. Quorum sensing-dependent biofilms enhance colonization in Vibrio cholerae. Dev Cell 5:647-656.