化膿性鏈球菌 (Streptococcus pyogenes)，俗稱A 群鏈球菌，是環境中常見的格蘭氏陽性病原菌，其致病的輕重程度，從無症狀感染，局部性的蜂窩性組織炎、咽喉炎、膿皰疹、非化膿性發炎併發症如風濕熱、急性腎絲球腎炎，以致於侵襲性感染如毒性休克症候群、壞死性肌膜炎...等。我們所要研究的主題是探討化膿性鏈球菌兩個毒力因子Streptopain (SPE B) 及 SPy0985 的核磁共振結構，藉由蛋白質的結構去探討其生理功能。SPE B是cysteine protease的成員之一，其特性具有辨識多種受質的能力，不僅能將 A 群鏈球菌表面的毒力因子(如:M protein、C5a peptidase)經由酵素切割方式釋放出來，更可以消化組織間的結構，造成宿主細胞的傷害。SPy0985是一種噬菌體關聯性的蛋白(phage-associated hypothetical protein)。過去的文獻指出，噬菌體感染細菌後，可能會增加細菌體本身的致病力，如增加菌體入侵、附著與生長的能力；抵抗免疫系統或抗生素的攻擊；或是轉譯出來的蛋白具有毒力。SPy0985 蛋白由88個胺基酸組成，其中第49至第75的胺基酸序列經由軟體預測分析結果認為具有超抗原的活性(superantigen activity)。有別過去利用X-ray 繞射法發表zymogen SPE B (zSPE B)的結構，利用核磁共振技術所解出的mature SPE B (mSPE B)結構可發現到C端圈環(A231 and A238)與催化環(V189 and A196) 有交互作用。且經由圖譜的觀察發現H195側鏈上的 H195 H 與G213 HN、W214 H、F197 H 具有距離的靠近，經由結構計算結果，H195側鏈方向是位在利於酵素進行催化反應的地方 (catalytically competent position)。所計算 mSPE B 的核磁共振結構已經呈遞RCSC Protein Data Bank，其檢索碼為2JTC。目前已利用大腸桿菌 (E. coli BL21) 成功表現SPy0985蛋白並予以純化，平均產率約為 30 mg/L。質譜儀分析重組蛋白SPy0985的分子量為9782.3 Da，與理論值差距小於1 Da 顯示蛋白的正確性。利用膠體色層分析法確認蛋白的分子量，發現在pH 5.5~pH 7.4的環境中，SPy0985可形成四聚體(tetramer)；週邊血液單核細胞增生測定 (PBM cell proliferation assay) 顯示其可能具有超抗原的活性。SPy0985蛋白可藉由鈣離子穩定蛋白的結構與溶解度。利用1H，15N，13C標定蛋白得到核磁共振光譜，並進行一級結構的循序判定 (sequential assignment) 與二級結構分析，確定在C端有形成兩個 -helices 並有交互作用；N 端則以 Y17、Y23、Y36 等疏水性胺基酸交互堆疊，這些結果將有助於探討SPy0985的致病機轉。

Streptococcus pyogenes, also known as group A streptococci (GAS), is a member of Gram positive bacteria and a common human pathogen in the environment. GAS causes a wide variety of diseases, including pharyngitis, impetigo, scarlet fever, cellulitis, toxic shock syndrome, necrotizing fasciitis, rheumatic fever, and acute glomerulonephritis. In this study I determined 3D structures of two virulence factors from GAS, including streptopain (SPE B) and SPy0985, by NMR spectroscopy. SPE B is a cysteine protease and can digest many kinds of substrates such as host proteins, proteoglycans, to help GAS to release surface virulent proteins like C5a peptidase and M protein, and then cause severe injury in the infected host. It is known that phage infection can enhance bacterial virulence, such as bacterial adhesion, colonization, invasion, resistance to immune defenses, exotoxin production, sensitivity to antibiotics, and transmissibility among humans. SPy0985 is a phage-associated hypothetical protein and contains 88 amino acid residues with a superantigen signature sequence at the positions of 49-75. In contrast to X-ray structure of 40-kDa zymogen SPE B (zSPE B), NMR structure of 28-kDa mature SPE B (mSPE B) found the interactions between the residues in the catalytic loop (V189 and A196) and the residues in the C-terminal loop (A231 and A238), which is unobserved in X-ray structure, and H195, the catalytic residue, is located at catalytically competent position. The structural differences are due to the insertion of N89p from the prodomain of zSPE B X-ray structure displacing H195 from the catalytically competent position. This was observed from NMR spectra that H of H195 interacted with the HN of G213, H of W214, and H of F197. The resulting 3D structures of mSPE B were deposited to Protein Data Bank (PDB) with the accession code 2JTC. I also have successfully expressed SPy0985 in E. coli and purified to homogeneity with a yield of 30 mg/L. The experimental molecular weight of recombinant Spy0985 was 9782.3 Da with a deviation of <1 compared with the calculated value. Molecular weight determination by gel filtration chromatography showed that Spy0985 is a tetramer. The results of peripheral blood mononuclear cell proliferation assay suggested that Spy0985 may act as a superantigen. Structural and functional analysis also showed that Spy0985 required calcium ion for its stability and activity. The 1H, 15N, and 13C resonance assignments of Spy0985 were obtained by analyzing triple resonance spectra. NMR analysis showed that Spy0985 consisted of two -helices at C terminal region, and a hydrophobic core packed by Y17, Y23 and Y36 at N terminal region. These studies will extend our understanding of the molecular basis of SPE B and SPy0985 in GAS infection.

Ahmed, S., and Ayoub, E.M. (1998). Severe, invasive group A streptococcal disease and toxic shock. Pediatric annals 27, 287-292.
Anderson, E.T., Winter, L.A., Fernsten, P., Olmsted, S.B., and Matsuka, Y.V. (2005). The pro-sequence domain of streptopain directs the folding of the mature enzyme. Archives of biochemistry and biophysics 436, 297-306.
Arcus, V.L., Proft, T., Sigrell, J.A., Baker, H.M., Fraser, J.D., and Baker, E.N. (2000). Conservation and variation in superantigen structure and activity highlighted by the three-dimensional structures of two new superantigens from Streptococcus pyogenes. Journal of molecular biology 299, 157-168.
Aziz, R.K., Ismail, S.A., Park, H.W., and Kotb, M. (2004). Post-proteomic identification of a novel phage-encoded streptodornase, Sda1, in invasive M1T1 Streptococcus pyogenes. Molecular microbiology 54, 184-197.
Berti, P.J., and Storer, A.C. (1995). Alignment/phylogeny of the papain superfamily of cysteine proteases. Journal of molecular biology 246, 273-283.
Bisno, A.L. (1979). Alternate complement pathway activation by group A streptococci: role of M-protein. Infection and immunity 26, 1172-1176.
Bisno, A.L., Brito, M.O., and Collins, C.M. (2003). Molecular basis of group A streptococcal virulence. The Lancet infectious diseases 3, 191-200.
Bisno, A.L., Rubin, F.A., Cleary, P.P., and Dale, J.B. (2005). Prospects for a group A streptococcal vaccine: rationale, feasibility, and obstacles--report of a National Institute of Allergy and Infectious Diseases workshop. Clin Infect Dis 41, 1150-1156.
Brunger, A.T. (1992). Free R value: a novel statistical quantity for assessing the accuracy of crystal structures. Nature 355, 472-475.
Canchaya, C., Proux, C., Fournous, G., Bruttin, A., and Brussow, H. (2003). Prophage genomics. Microbiol Mol Biol Rev 67, 238-276, table of contents.
Chen, C.Y., Luo, S.C., Kuo, C.F., Lin, Y.S., Wu, J.J., Lin, M.T., Liu, C.C., Jeng, W.Y., and Chuang, W.J. (2003). Maturation processing and characterization of streptopain. The Journal of biological chemistry 278, 17336-17343.
Cleary, P.P. (2006). Streptococcus moves inward. Nature medicine 12, 384-386.
Collin, M., and Olsen, A. (2001). Effect of SpeB and EndoS from Streptococcus pyogenes on human immunoglobulins. Infection and immunity 69, 7187-7189.
Courtney, H.S., Hasty, D.L., and Dale, J.B. (2002). Molecular mechanisms of adhesion, colonization, and invasion of group A streptococci. Annals of medicine 34, 77-87.
Cunningham, M.W. (2000). Pathogenesis of group A streptococcal infections. Clinical microbiology reviews 13, 470-511.
Dale, J.B., Washburn, R.G., Marques, M.B., and Wessels, M.R. (1996). Hyaluronate capsule and surface M protein in resistance to opsonization of group A streptococci. Infection and immunity 64, 1495-1501.
Doran, J.D., Nomizu, M., Takebe, S., Menard, R., Griffith, D., and Ziomek, E. (1999). Autocatalytic processing of the streptococcal cysteine protease zymogen: processing mechanism and characterization of the autoproteolytic cleavage sites. European journal of biochemistry / FEBS 263, 145-151.
Eriksson, A., and Norgren, M. (1999). The superantigenic activity of streptococcal pyrogenic exotoxin B is independent of the protease activity. FEMS immunology and medical microbiology 25, 355-363.
Federle, M.J., McIver, K.S., and Scott, J.R. (1999). A response regulator that represses transcription of several virulence operons in the group A streptococcus. Journal of bacteriology 181, 3649-3657.
Ferretti, J.J., McShan, W.M., Ajdic, D., Savic, D.J., Savic, G., Lyon, K., Primeaux, C., Sezate, S., Suvorov, A.N., Kenton, S., et al. (2001). Complete genome sequence of an M1 strain of Streptococcus pyogenes. Proceedings of the National Academy of Sciences of the United States of America 98, 4658-4663.
Gong, H., Murphy, A., McMaster, C.R., and Byers, D.M. (2007). Neutralization of acidic residues in helix II stabilizes the folded conformation of acyl carrier protein and variably alters its function with different enzymes. The Journal of biological chemistry 282, 4494-4503.
Graham, M.R., Smoot, L.M., Migliaccio, C.A., Virtaneva, K., Sturdevant, D.E., Porcella, S.F., Federle, M.J., Adams, G.J., Scott, J.R., and Musser, J.M. (2002). Virulence control in group A Streptococcus by a two-component gene regulatory system: global expression profiling and in vivo infection modeling. Proceedings of the National Academy of Sciences of the United States of America 99, 13855-13860.
Gubba, S., Cipriano, V., and Musser, J.M. (2000). Replacement of histidine 340 with alanine inactivates the group A Streptococcus extracellular cysteine protease virulence factor. Infection and immunity 68, 3716-3719.
Herwald, H., Collin, M., Muller-Esterl, W., and Bjorck, L. (1996). Streptococcal cysteine proteinase releases kinins: a virulence mechanism. The Journal of experimental medicine 184, 665-673.
Horstmann, R.D., Sievertsen, H.J., Knobloch, J., and Fischetti, V.A. (1988). Antiphagocytic activity of streptococcal M protein: selective binding of complement control protein factor H. Proceedings of the National Academy of Sciences of the United States of America 85, 1657-1661.
Hsueh, P.R., Wu, J.J., Tsai, P.J., Liu, J.W., Chuang, Y.C., and Luh, K.T. (1998). Invasive group A streptococcal disease in Taiwan is not associated with the presence of streptococcal pyrogenic exotoxin genes. Clin Infect Dis 26, 584-589.
Ji, Y., McLandsborough, L., Kondagunta, A., and Cleary, P.P. (1996). C5a peptidase alters clearance and trafficking of group A streptococci by infected mice. Infection and immunity 64, 503-510.
Johnson, D.R., Stevens, D.L., and Kaplan, E.L. (1992). Epidemiologic analysis of group A streptococcal serotypes associated with severe systemic infections, rheumatic fever, or uncomplicated pharyngitis. The Journal of infectious diseases 166, 374-382.
Kagawa, T.F., Cooney, J.C., Baker, H.M., McSweeney, S., Liu, M., Gubba, S., Musser, J.M., and Baker, E.N. (2000). Crystal structure of the zymogen form of the group A Streptococcus virulence factor SpeB: an integrin-binding cysteine protease. Proceedings of the National Academy of Sciences of the United States of America 97, 2235-2240.
Kagawa, T.F., O'Toole P, W., and Cooney, J.C. (2005). SpeB-Spi: a novel protease-inhibitor pair from Streptococcus pyogenes. Molecular microbiology 57, 650-666.
Kapur, V., Majesky, M.W., Li, L.L., Black, R.A., and Musser, J.M. (1993a). Cleavage of interleukin 1 beta (IL-1 beta) precursor to produce active IL-1 beta by a conserved extracellular cysteine protease from Streptococcus pyogenes. Proceedings of the National Academy of Sciences of the United States of America 90, 7676-7680.
Kapur, V., Topouzis, S., Majesky, M.W., Li, L.L., Hamrick, M.R., Hamill, R.J., Patti, J.M., and Musser, J.M. (1993b). A conserved Streptococcus pyogenes extracellular cysteine protease cleaves human fibronectin and degrades vitronectin. Microbial pathogenesis 15, 327-346.
Kreikemeyer, B., McIver, K.S., and Podbielski, A. (2003). Virulence factor regulation and regulatory networks in Streptococcus pyogenes and their impact on pathogen-host interactions. Trends in microbiology 11, 224-232.
Levin, J.C., and Wessels, M.R. (1998). Identification of csrR/csrS, a genetic locus that regulates hyaluronic acid capsule synthesis in group A Streptococcus. Molecular microbiology 30, 209-219.
Li, H., Llera, A., Malchiodi, E.L., and Mariuzza, R.A. (1999). The structural basis of T cell activation by superantigens. Annual review of immunology 17, 435-466.
Li, Y., Li, H., Dimasi, N., McCormick, J.K., Martin, R., Schuck, P., Schlievert, P.M., and Mariuzza, R.A. (2001). Crystal structure of a superantigen bound to the high-affinity, zinc-dependent site on MHC class II. Immunity 14, 93-104.
Madden, J.C., Ruiz, N., and Caparon, M. (2001). Cytolysin-mediated translocation (CMT): a functional equivalent of type III secretion in gram-positive bacteria. Cell 104, 143-152.
Mallorqui-Fernandez, N., Manandhar, S.P., Mallorqui-Fernandez, G., Uson, I., Wawrzonek, K., Kantyka, T., Sola, M., Thogersen, I.B., Enghild, J.J., Potempa, J., et al. (2008). A new autocatalytic activation mechanism for cysteine proteases revealed by Prevotella intermedia interpain A. The Journal of biological chemistry 283, 2871-2882.
Michiels, J., Xi, C., Verhaert, J., and Vanderleyden, J. (2002). The functions of Ca(2+) in bacteria: a role for EF-hand proteins? Trends in microbiology 10, 87-93.
Mora, M., Bensi, G., Capo, S., Falugi, F., Zingaretti, C., Manetti, A.G., Maggi, T., Taddei, A.R., Grandi, G., and Telford, J.L. (2005). Group A Streptococcus produce pilus-like structures containing protective antigens and Lancefield T antigens. Proceedings of the National Academy of Sciences of the United States of America 102, 15641-15646.
Musser, J.M., Hauser, A.R., Kim, M.H., Schlievert, P.M., Nelson, K., and Selander, R.K. (1991). Streptococcus pyogenes causing toxic-shock-like syndrome and other invasive diseases: clonal diversity and pyrogenic exotoxin expression. Proceedings of the National Academy of Sciences of the United States of America 88, 2668-2672.
Musser, J.M., Stockbauer, K., Kapur, V., and Rudgers, G.W. (1996). Substitution of cysteine 192 in a highly conserved Streptococcus pyogenes extracellular cysteine protease (interleukin 1beta convertase) alters proteolytic activity and ablates zymogen processing. Infection and immunity 64, 1913-1917.
Nagamune, H., Ohkura, K., and Ohkuni, H. (2005). Molecular basis of group A streptococcal pyrogenic exotoxin B. J Infect Chemother 11, 1-8.
Nakagawa, I., Amano, A., Mizushima, N., Yamamoto, A., Yamaguchi, H., Kamimoto, T., Nara, A., Funao, J., Nakata, M., Tsuda, K., et al. (2004). Autophagy defends cells against invading group A Streptococcus. Science (New York, NY 306, 1037-1040.
Nizet, V. (2002). Streptococcal beta-hemolysins: genetics and role in disease pathogenesis. Trends in microbiology 10, 575-580.
Nizet, V. (2007). Understanding how leading bacterial pathogens subvert innate immunity to reveal novel therapeutic targets. The Journal of allergy and clinical immunology 120, 13-22.
Nomizu, M., Pietrzynski, G., Kato, T., Lachance, P., Menard, R., and Ziomek, E. (2001). Substrate specificity of the streptococcal cysteine protease. The Journal of biological chemistry 276, 44551-44556.
Norris, V., Chen, M., Goldberg, M., Voskuil, J., McGurk, G., and Holland, I.B. (1991). Calcium in bacteria: a solution to which problem? Molecular microbiology 5, 775-778.
Norris, V., Grant, S., Freestone, P., Canvin, J., Sheikh, F.N., Toth, I., Trinei, M., Modha, K., and Norman, R.I. (1996). Calcium signalling in bacteria. Journal of bacteriology 178, 3677-3682.
Ohara-Nemoto, Y., Sasaki, M., Kaneko, M., Nemoto, T., and Ota, M. (1994). Cysteine protease activity of streptococcal pyrogenic exotoxin B. Canadian journal of microbiology 40, 930-936.
Ohkuni, H., Todome, Y., Watanabe, Y., Ishikaw, T., Takahashi, H., Kannari, Y., Kato, H., Uchiyama, T., Saito, H., Fischetti, V.A., et al. (2004). Studies of recombinant streptococcal pyrogenic exotoxin B/cysteine protease (rSPE B/SCP) in the skin of guinea pigs & the release of histamine from cultured mast cells & basophilic leukocytes. The Indian journal of medical research 119 Suppl, 33-36.
Otlewski, J., Jelen, F., Zakrzewska, M., and Oleksy, A. (2005). The many faces of protease-protein inhibitor interaction. The EMBO journal 24, 1303-1310.
Papageorgiou, A.C., and Acharya, K.R. (2000). Microbial superantigens: from structure to function. Trends in microbiology 8, 369-375.
Perez-Casal, J., Caparon, M.G., and Scott, J.R. (1991). Mry, a trans-acting positive regulator of the M protein gene of Streptococcus pyogenes with similarity to the receptor proteins of two-component regulatory systems. Journal of bacteriology 173, 2617-2624.
Pinkney, M., Kapur, V., Smith, J., Weller, U., Palmer, M., Glanville, M., Messner, M., Musser, J.M., Bhakdi, S., and Kehoe, M.A. (1995). Different forms of streptolysin O produced by Streptococcus pyogenes and by Escherichia coli expressing recombinant toxin: cleavage by streptococcal cysteine protease. Infection and immunity 63, 2776-2779.
Proft, T., Arcus, V.L., Handley, V., Baker, E.N., and Fraser, J.D. (2001). Immunological and biochemical characterization of streptococcal pyrogenic exotoxins I and J (SPE-I and SPE-J) from Streptococcus pyogenes. J Immunol 166, 6711-6719.
Rawlings, N.D., and Barrett, A.J. (1994). Families of cysteine peptidases. Methods in enzymology 244, 461-486.
Roussel, A., Anderson, B.F., Baker, H.M., Fraser, J.D., and Baker, E.N. (1997). Crystal structure of the streptococcal superantigen SPE-C: dimerization and zinc binding suggest a novel mode of interaction with MHC class II molecules. Nature structural biology 4, 635-643.
Rzychon, M., Chmiel, D., and Stec-Niemczyk, J. (2004). Modes of inhibition of cysteine proteases. Acta biochimica Polonica 51, 861-873.
Schleberger, C., Hochmann, H., Barth, H., Aktories, K., and Schulz, G.E. (2006). Structure and action of the binary C2 toxin from Clostridium botulinum. Journal of molecular biology 364, 705-715.
Schmidtchen, A., Frick, I.M., and Bjorck, L. (2001). Dermatan sulphate is released by proteinases of common pathogenic bacteria and inactivates antibacterial alpha-defensin. Molecular microbiology 39, 708-713.
Shanley, T.P., Schrier, D., Kapur, V., Kehoe, M., Musser, J.M., and Ward, P.A. (1996). Streptococcal cysteine protease augments lung injury induced by products of group A streptococci. Infection and immunity 64, 870-877.
Sriskandan, S., Faulkner, L., and Hopkins, P. (2007). Streptococcus pyogenes: Insight into the function of the streptococcal superantigens. The international journal of biochemistry & cell biology 39, 12-19.
Stevens, D.L. (1992). Invasive group A streptococcus infections. Clin Infect Dis 14, 2-11.
Stevens, D.L. (1996). Invasive group A streptococcal disease. Infectious agents and disease 5, 157-166.
Stevens, D.L. (2000). Streptococcal toxic shock syndrome associated with necrotizing fasciitis. Annual review of medicine 51, 271-288.
Stollerman, G.H. (1988). Changing group A streptococci. The reappearance of streptococcal 'toxic shock'. Archives of internal medicine 148, 1268-1270.
Straley, S.C., Plano, G.V., Skrzypek, E., Haddix, P.L., and Fields, K.A. (1993). Regulation by Ca2+ in the Yersinia low-Ca2+ response. Molecular microbiology 8, 1005-1010.
Sun, H., Ringdahl, U., Homeister, J.W., Fay, W.P., Engleberg, N.C., Yang, A.Y., Rozek, L.S., Wang, X., Sjobring, U., and Ginsburg, D. (2004). Plasminogen is a critical host pathogenicity factor for group A streptococcal infection. Science (New York, NY 305, 1283-1286.
Sundberg, E.J., Li, H., Llera, A.S., McCormick, J.K., Tormo, J., Schlievert, P.M., Karjalainen, K., and Mariuzza, R.A. (2002). Structures of two streptococcal superantigens bound to TCR beta chains reveal diversity in the architecture of T cell signaling complexes. Structure 10, 687-699.
Tai, J.Y., Kortt, A.A., Liu, T.Y., and Elliott, S.D. (1976). Primary structure of streptococcal proteinase. III. Isolation of cyanogen bromide peptides: complete covalent structure of the polypeptide chain. The Journal of biological chemistry 251, 1955-1959.
Tisa, L.S., and Adler, J. (1992). Calcium ions are involved in Escherichia coli chemotaxis. Proceedings of the National Academy of Sciences of the United States of America 89, 11804-11808.
Tisa, L.S., and Adler, J. (1995). Cytoplasmic free-Ca2+ level rises with repellents and falls with attractants in Escherichia coli chemotaxis. Proceedings of the National Academy of Sciences of the United States of America 92, 10777-10781.
Trombe, M.C., Rieux, V., and Baille, F. (1994). Mutations which alter the kinetics of calcium transport alter the regulation of competence in Streptococcus pneumoniae. Journal of bacteriology 176, 1992-1996.
Tsai, P.J., Kuo, C.F., Lin, K.Y., Lin, Y.S., Lei, H.Y., Chen, F.F., Wang, J.R., and Wu, J.J. (1998). Effect of group A streptococcal cysteine protease on invasion of epithelial cells. Infection and immunity 66, 1460-1466.
Tsai, W.H., Chang, C.W., Chuang, W.J., Lin, Y.S., Wu, J.J., Liu, C.C., Chang, W.T., and Lin, M.T. (2004). Streptococcal pyrogenic exotoxin B-induced apoptosis in a549 cells is mediated by a receptor- and mitochondrion-dependent pathway. Infection and immunity 72, 7055-7062.
Tsao, N., Tsai, W.H., Lin, Y.S., Chuang, W.J., Wang, C.H., and Kuo, C.F. (2006). Streptococcal pyrogenic exotoxin B cleaves properdin and inhibits complement-mediated opsonophagocytosis. Biochemical and biophysical research communications 339, 779-784.
Turk, D., and Guncar, G. (2003). Lysosomal cysteine proteases (cathepsins): promising drug targets. Acta crystallographica 59, 203-213.
Turner, C., and Sriskandan, S. (2007). Streptococcus pyogenes under pressure. Nature medicine 13, 909-910.
Wagner, P.L., and Waldor, M.K. (2002). Bacteriophage control of bacterial virulence. Infection and immunity 70, 3985-3993.
Watanabe, Y., Todome, Y., Ohkuni, H., Sakurada, S., Ishikawa, T., Yutsudo, T., Fischetti, V.A., and Zabriskie, J.B. (2002). Cysteine protease activity and histamine release from the human mast cell line HMC-1 stimulated by recombinant streptococcal pyrogenic exotoxin B/streptococcal cysteine protease. Infection and immunity 70, 3944-3947.
Wessels, M.R. (1999). Regulation of virulence factor expression in group A streptococcus. Trends in microbiology 7, 428-430.
Wexler, D.E., Chenoweth, D.E., and Cleary, P.P. (1985). Mechanism of action of the group A streptococcal C5a inactivator. Proceedings of the National Academy of Sciences of the United States of America 82, 8144-8148.
Yu, X.C., and Margolin, W. (1997). Ca2+-mediated GTP-dependent dynamic assembly of bacterial cell division protein FtsZ into asters and polymer networks in vitro. The EMBO journal 16, 5455-5463.
Zamoyska, R. (2006). Superantigens: supersignalers? Sci STKE 2006, pe45.
王志傑 Streptopain 核磁共振之研究：C 端及催化圈環對於與抑制劑結合及蛋白酶活性所扮演的角色 (2006)
王佩如 熱原性鏈球菌外毒素 B 多型性及突變株的特性之研究。 國立成功大學生物化學研究所碩士論文 (2005)
陳秋月 化膿性鏈球菌外毒素 B 的表現和特性之研究。國立成功大學生物化學研究所碩士論文 (1999)
黃湘琦 熱原性鏈球菌外毒素 B 與其突變株 C47S 的結構與功能關係之探討。 國立成功大學生物化學研究所碩士論文 (2004)。