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Chapter 1 : What Is a Pneumococcus?

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Abstract:

The pneumococcus ( or diplococcus) has been profoundly important in the understanding of the human response to infectious disease, the nature of genetic material, and natural transformation as a means of genetic exchange, as well as in the recognition of bacterial resistance to drugs. To develop effective diagnostic tools for the pneumococcus, one has to understand more about its nearest neighbors and include the breadth of diversity of these organisms in strain panels used to validate diagnostic tools—unfortunately, this tends to be the exception rather than the rule. The pneumolysin and autolysin genes have been flagged as potentially useful targets for molecular diagnostics for the past decade or so, and reports throughout this time have always found typical human clinical pneumococci to possess and . This probable pathogenicity island (PPI-1) represents one example of no doubt other events that will be revealed by comparative genomics, which has contributed to the evolution of the founding pneumococcus from which the extant population has arisen. A hypothesis was constructed to account for these novel phenotypes and the role of in pneumococci. However, the development of a diagnostic test based upon single-target identification might be an ambitious hope given the genetic plasticity of the pneumococcus and its naturally transformable relatives.

Citation: Dowson C. 2004. What Is a Pneumococcus?, p 1-14. In Tuomanen E, Mitchell T, Morrison D, Spratt B (ed), The Pneumococcus. ASM Press, Washington, DC. doi: 10.1128/9781555816537.ch1

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Multilocus Sequence Typing
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16s rRNA Sequencing
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Horizontal Gene Transfer
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FIGURE 1

Dendrogram of genetic relationships between streptococcal isolates described by Whatmore et al. ( ) and the presence or absence of characteristic pneumococcal diagnostic features. The dendrogram was constructed from housekeeping gene sequence data () by using the neighbor-joining method. Only bootstrap confidence values exceeding 90% are shown. The scale represents the number of nucleotide substitutions per site. Overall identities of strains clustering together either as atypical organisms, , and are indicated by arrows. Features include optochin susceptibility (?), optochin intermediate resistance (□), bile solubility (insert image), presence of an identified pneumococcal capsule (insert image), presence of the pneumolysin gene (?), and presence of the major autolysin gene (?). Strains deficient in these characteristics are highlighted black. Strains, identified here as using three loci and in a previous study examining nine different loci ( ), arise from a common node with a bootstrap value of 100. Within this group two clusters were identified as a and b. Cluster b isolates, though clearly pneumococci, were all acapsulate, with one isolate exhibiting bile insolubility and another exhibiting intermediate optochin resistance. One acapsulate isolate was identified within cluster a. Atypical organisms, arising at node c, represent a rather diffuse collection of strains but are clearly separated from typical strains of and from strains identified as and . Strains identified as form an ill-defined group the bulk of which arise at node d. Strains identified as form a clearly distinguishable group arising at node e. What is interesting is the genetic conservation within pneumococci, compared to the diversity found among and even greater diversity among isolates of .

Citation: Dowson C. 2004. What Is a Pneumococcus?, p 1-14. In Tuomanen E, Mitchell T, Morrison D, Spratt B (ed), The Pneumococcus. ASM Press, Washington, DC. doi: 10.1128/9781555816537.ch1
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Image of FIGURE 2
FIGURE 2

Condensed dendrogram of genetic relationships between the strain carrying the proposed Norway 4 mutation (in bold) described by Novak et al. ( ) and a panel of genetically diverse well-characterized strains of (including strains Norway 4[ ] and R6 [ ]) atypical organisms, and ( ). The dendrogram was constructed by the neighbor-joining method using the program within MEGA version 2.1 ( ). The scale represents the number of nucleotide substitutions per site.

Citation: Dowson C. 2004. What Is a Pneumococcus?, p 1-14. In Tuomanen E, Mitchell T, Morrison D, Spratt B (ed), The Pneumococcus. ASM Press, Washington, DC. doi: 10.1128/9781555816537.ch1
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References

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1. Austrian, R. 1981. Pneumococcus: the first one hundred years. Rev. Infect. Dis. 3:183189.
2. Balachandran, P.,, S. K. Hollingshead,, J. C. Paton,, and D. E. Briles. 2001. The autolytic enzyme LytA of Streptococcus pneumoniae is not responsible for releasing pneumolysin. J. Bacteriol. 183:31083116.
3. Berge, M.,, P. Garcia,, F. Iannelli,, M. F. Prere,, C. Granadel,, A. Polissi,, and J. P. Claverys. 2001. The puzzle of zmpB and extensive chain formation, autolysis defect and nontranslocation of choline-binding proteins in Streptococcus pneumoniae. Mol. Microbiol. 39:16511660.
4. Broome, C. V.,, and R. R. Facklam. 1981. Epidemiology of clinically significant isolates of Streptococcus pneumoniae in the United States. Rev. Infect. Dis. 3:277281.
5. Brown, J. S.,, S. M. Gilliland,, and D. W. Holden. 2001. A Streptococcus pneumoniae pathogenicity island encoding an ABC transporter involved in iron uptake and virulence. Mol. Microbiol. 40:572585.
6. Butler, J. C.,, S. C. Bosshardt,, M. Phelan,, S. M. Moroney,, M. L. Tondella,, M. M. Farley,, A. Schuchat,, and B. S. Fields. 2003. Classical and latent class analysis evaluation of sputum polymerase chain reaction and urine antigen testing for diagnosis of pneumococcal pneumonia in adults. J. Infect. Dis. 187:14161423.
7. Chandler, L. J.,, B. S. Reisner,, G. L. Woods,, and A. K. Jafri. 2000. Comparison of four methods for identifying Streptococcus pneumoniae. Diagn. Microbiol. Infect. Dis. 37:285287.
8. Darkes, M. J.,, and G. L. Plosker. 2002. Pneumococcal conjugate vaccine (Prevnar; PNCRM7): a review of its use in the prevention of Streptococcus pneumoniae infection. Paediatr. Drugs 4:609630.
9. Denys, G. A.,, and R. B. Carey. 1992. Identification of Streptococcus pneumoniae with a DNA probe. J. Clin. Microbiol. 30:27252727.
10. Diaz, E.,, and J. L. Garcia. 1990. Characterization of the transcription unit encoding the major pneumococcal autolysin. Gene 90:157162.
11. Diaz, E.,, R. Lopez,, and J. L. Garcia. 1990. Chimeric phage-bacterial enzymes: a clue to the modular evolution of genes. Proc. Natl. Acad. Sci. USA 87:81258129.
12. Dowson, C. G.,, V. Barcus,, S. King,, P. Pickerill,, A. Whatmore,, and M. Yeo. 1997. Horizontal gene transfer and the evolution of resistance and virulence determinants in Streptococcus. Soc. Appl. Bacteriol. Symp. Ser. 26:42S51S.
13. Dowson, C. G.,, T. J. Coffey,, C. Kell,, and R. A. Whiley. 1993. Evolution of penicillin resistance in Streptococcus pneumoniae; the role of Streptococcus mitis in the formation of a low affinity PBP2B in S. pneumoniae. Mol. Microbiol. 9:635643.
14. Dowson, C. G.,, A. Hutchison,, J. A. Brannigan,, R. C. George,, D. Hansman,, J. Linares,, A. Tomasz,, J. M. Smith,, and B. G. Spratt. 1989. Horizontal transfer of penicillin-binding protein genes in penicillin-resistant clinical isolates of Streptococcus pneumoniae. Proc. Natl. Acad. Sci. USA 86:88428846.
15. Dowson, C. G.,, A. Hutchison,, N. Woodford,, A. P. Johnson,, R. C. George,, and B. G. Spratt. 1990. Penicillin-resistant viridans streptococci have obtained altered penicillinbinding protein genes from penicillin-resistant strains of Streptococcus pneumoniae. Proc. Natl. Acad. Sci. USA 87:58585862.
16. Dowson, C. G.,, and K. Trzcinski (ed.). 2001. Evolution and Epidemiology of Antibiotic Resistant Pneumococci. Marcel Dekker, Inc., New York, N.Y.
17. du Plessis, M.,, A. M. Smith,, and K. P. Klugman. 1998. Rapid detection of penicillin- resistant Streptococcus pneumoniae in cerebrospinal fluid by a seminested-PCR strategy. J. Clin. Microbiol. 36:453457.
18. Enright, M. C.,, and B. G. Spratt. 1999. Extensive variation in the ddl gene of penicillin-resistant Streptococcus pneumoniae results from a hitchhiking effect driven by the penicillin-binding protein 2b gene. Mol. Biol. Evol. 16:16871695.
19. Enright, M. C.,, and B. G. Spratt. 1998. A multilocus sequence typing scheme for Streptococcus pneumoniae: identification of clones associated with serious invasive disease. Microbiology 144 (Pt. 11):30493060.
20. Falguera, M.,, A. Lopez,, A. Nogues,, J. M. Porcel,, and M. Rubio-Caballero. 2002. Evaluation of the polymerase chain reaction method for detection of Streptococcus pneumoniae DNA in pleural fluid samples. Chest 122:22122216.
21. Feil, E. J.,, J. M. Smith,, M. C. Enright,, and B. G. Spratt. 2000. Estimating recombinational parameters in Streptococcus pneumoniae from multilocus sequence typing data. Genetics 154:14391450.
22. Fenoll, A.,, R. Munoz,, E. Garcia,, and A. G. de la Campa. 1994. Molecular basis of the optochin- sensitive phenotype of pneumococcus: characterization of the genes encoding the F0 complex of the Streptococcus pneumoniae and Streptococcus oralis H(+)-ATPases. Mol. Microbiol. 12:587598.
23. Finland, M.,, and M. W. Barnes. 1977. Changes in the occurrence of capsular serotypes of Streptococcus pneumoniae in Boston City Hospital during selected years between 1935 and 1974. J. Clin. Microbiol. 5:154166.
24. Gillespie, S. H.,, T. D. McHugh,, H. Ayres,, A. Dickens,, A. Efstratiou,, and G. C. Whiting. 1997. Allelic variation in Streptococcus pneumoniae autolysin (N-acetyl muramoyl-L-alanine amidase). Infect. Immun. 65:39363938.
25. Gillespie, S. H.,, C. Ullman,, M. D. Smith,, and V. Emery. 1994. Detection of Streptococcus pneumoniae in sputum samples by PCR. J. Clin. Microbiol. 32:13081311.
26. Greiner, O.,, P. J. Day,, P. P. Bosshard,, F. Imeri,, M. Altwegg,, and D. Nadal. 2001. Quantitative detection of Streptococcus pneumoniae in nasopharyngeal secretions by real-time PCR. J. Clin. Microbiol. 39:31293134.
27. Henrichsen, J. 1999. Typing of Streptococcus pneumoniae: past, present, and future. Am. J. Med. 107:50S54S.
28. Hollingshead, S. K.,, R. Becker,, and D. E. Briles. 2000. Diversity of PspA: mosaic genes and evidence for past recombination in Streptococcus pneumoniae. Infect. Immun. 68:58895900.
29. Holmberg, H.,, D. Danielsson,, J. Hardie,, A. Krook,, and R. Whiley. 1985. Cross-reactions between alpha-streptococci and Omniserum, a polyvalent pneumococcal serum, demonstrated by direct immunofluorescence, immunoelectroosmophoresis, and latex agglutination. J. Clin. Microbiol. 21:745748.
30. Iannelli, F.,, M. R. Oggioni,, and G. Pozzi. 2002. Allelic variation in the highly polymorphic locus pspC of Streptococcus pneumoniae. Gene 284:6371.
31. Kaijalainen, T.,, S. Rintamaki,, E. Herva,, and M. Leinonen. 2002. Evaluation of genetechnological and conventional methods in the identification of Streptococcus pneumoniae. J. Microbiol. Methods 51:111118.
32. Kawamura, Y.,, X. G. Hou,, Y. Todome,, F. Sultana,, K. Hirose,, S. E. Shu,, T. Ezaki,, and H. Ohkuni. 1998. Streptococcus peroris sp. nov. and Streptococcus infantis sp. nov., new members of the Streptococcus mitis group, isolated from human clinical specimens. Int. J. Syst. Bacteriol. 48:921927.
33. Kawamura, Y.,, R. A. Whiley,, S. E. Shu,, T. Ezaki,, and J. M. Hardie. 1999. Genetic approaches to the identification of the mitis group within the genus Streptococcus. Microbiology 145 (Pt. 9):26052613.
34. Kearns, A. M.,, J. Wheeler,, R. Freeman,, P. R. Seiders,, J. Perry,, A. M. Whatmore,, and C. G. Dowson. 2000. Pneumolysin detection identifies atypical isolates of Streptococcus pneumoniae. J. Clin. Microbiol. 38:13091310.
35. Kellogg, J. A.,, D. A. Bankert,, C. J. Elder,, J. L. Gibbs,, and M. C. Smith. 2001. Identification of Streptococcus pneumoniae revisited. J. Clin. Microbiol. 39:33733375.
36. Kim, J. O.,, and J. N. Weiser. 1998. Association of intrastrain phase variation in quantity of capsular polysaccharide and teichoic acid with the virulence of Streptococcus pneumoniae. J. Infect. Dis. 177:368377.
37. Kontiainen, S.,, and A. Sivonen. 1987. Optochin resistance in Streptococcus pneumoniae strains isolated from blood and middle ear fluid. Eur. J. Clin. Microbiol. 6:422424.
38. Kumar, S.,, K. Tamura,, I. B. Jakobsen,, and M. Nei. 2001. MEGA2: molecular evolutionary genetics analysis software. Bioinformatics 17:12441245.
39. Lee, C. J.,, S. D. Banks,, and J. P. Li. 1991. Virulence, immunity, and vaccine related to Streptococcus pneumoniae. Crit. Rev. Microbiol. 18:89114.
40. Llull, D.,, R. Lopez,, and E. Garcia. 2000. Clonal origin of the type 37 Streptococcus pneumoniae. Microb. Drug Resist. 6:269275.
41. Lock, R. A.,, Q. Y. Zhang,, A. M. Berry,, and J. C. Paton. 1996. Sequence variation in the Streptococcus pneumoniae pneumolysin gene affecting haemolytic activity and electrophoretic mobility of the toxin. Microb. Pathog. 21:7183.
42. Majewski, J.,, P. Zawadzki,, P. Pickerill,, F. M. Cohan,, and C. G. Dowson. 2000. Barriers to genetic exchange between bacterial species: Streptococcus pneumoniae transformation. J. Bacteriol. 182:10161023.
43. Martin, M.,, J. H. Turco,, M. E. Zegans,, R. R. Facklam,, S. Sodha,, J. A. Elliott,, J. H. Pryor,, B. Beall,, D. D. Erdman,, Y. Y. Baumgartner,, P. A. Sanchez,, J. D. Schwartzman,, J. Montero,, A. Schuchat,, and C. G. Whitney. 2003. An outbreak of conjunctivitis due to atypical Streptococcus pneumoniae. N. Engl. J. Med. 348:11121121.
44. Martín-Galiano, A. J.,, L. Balsalobre,, A. Fenoll,, and A. G. de Fla Campa. 2003. Genetic characterization of optochin-susceptible viridans group streptococci. Antimicrob. Agents Chemother. 47:31873194.
45. McAvin, J. C.,, P. A. Reilly,, R. M. Roudabush,, W. J. Barnes,, A. Salmen,, G. W. Jackson,, K. K. Beninga,, A. Astorga,, F. K. Mc- Cleskey,, W. B. Huff,, D. Niemeyer,, and K. L. Lohman. 2001. Sensitive and specific method for rapid identification of Streptococcus pneumoniae using real-time fluorescence PCR. J. Clin. Microbiol. 39:34463451.
46. McCool, T. L.,, T. R. Cate,, E. I. Tuomanen,, P. Adrian,, T. J. Mitchell,, and J. N. Weiser. 2003. Serum immunoglobulin G response to candidate vaccine antigens during experimental human pneumococcal colonization. Infect. Immun. 71:57245732.
47. Meats, E.,, A. B. Brueggemann,, M. C. Enright,, K. Sleeman,, D. T. Griffiths,, D. W. Crook,, and B. G. Spratt. 2003. Stability of serotypes during nasopharyngeal carriage of Streptococcus pneumoniae. J. Clin. Microbiol. 41:386392.
48. Morona, J. K.,, R. Morona,, and J. C. Paton. 1999. Analysis of the 5′ portion of the type 19A capsule locus identifies two classes of cpsC, cpsD, and cpsE genes in Streptococcus pneumoniae. J. Bacteriol. 181:35993605.
49. Morrison, K. E.,, D. Lake,, J. Crook,, G. M. Carlone,, E. Ades,, R. Facklam,, and J. S. Sampson. 2000. Confirmation of psaA in all 90 serotypes of Streptococcus pneumoniae by PCR and potential of this assay for identification and diagnosis. J. Clin. Microbiol. 38:434437.
50. Muller-Graf, C. D.,, A. M. Whatmore,, S. J. King,, K. Trzcinski,, A. P. Pickerill,, N. Doherty,, J. Paul,, D. Griffiths,, D. Crook,, and C. G. Dowson. 1999. Population biology of Streptococcus pneumoniae isolated from oropharyngeal carriage and invasive disease. Microbiology 145:32833293.
51. Mundy, L. S.,, E. N. Janoff,, K. E. Schwebke,, C. J. Shanholtzer,, and K. E. Willard. 1998. Ambiguity in the identification of Streptococcus pneumoniae. Optochin, bile solubility, quellung, and the AccuProbe DNA probe tests. Am. J. Clin. Pathol. 109:5561.
52. Munoz, R.,, A. Fenoll,, D. Vicioso,, and J. Casal. 1990. Optochin-resistant variants of Streptococcus pneumoniae. Diagn. Microbiol. Infect. Dis. 13:6366.
53. Murdoch, D. R.,, T. P. Anderson,, K. A. Beynon,, A. Chua,, A. M. Fleming,, R. T. Laing,, G. I. Town,, G. D. Mills,, S. T. Chambers,, and L. C. Jennings. 2003. Evaluation of a PCR assay for detection of Streptococcus pneumoniae in respiratory and nonrespiratory samples from adults with community-acquired pneumonia. J. Clin. Microbiol. 41:6366.
54. Novak, R.,, E. Charpentier,, J. S. Braun,, E. Park,, S. Murti,, E. Tuomanen,, and R. Masure. 2000. Extracellular targeting of cholinebinding proteins in Streptococcus pneumoniae by a zinc metalloprotease. Mol. Microbiol. 36:366376.
55. Obregon, V.,, P. Garcia,, E. Garcia,, A. Fenoll,, R. Lopez,, and J. L. Garcia. 2002. Molecular peculiarities of the lytA gene isolated from clinical pneumococcal strains that are bile insoluble. J. Clin. Microbiol. 40:25452554.
56. O’Brien, K. L.,, M. A. Bronsdon,, R. Dagan,, P. Yagupsky,, J. Janco,, J. Elliott,, C. G. Whitney,, Y. H. Yang,, L. G. Robinson,, B. Schwartz,, and G. M. Carlone. 2001. Evaluation of a medium (STGG) for transport and optimal recovery of Streptococcus pneumoniae from nasopharyngeal secretions collected during field studies. J. Clin. Microbiol. 39:10211024.
57. O’Brien, K. L.,, and H. Nohynek. 2003. Report from a WHO working group: standard method for detecting upper respiratory carriage of Streptococcus pneumoniae. Pediatr. Infect. Dis. J. 22:133140.
58. Oggioni, M. R.,, G. Memmi,, T. Maggi,, D. Chiavolini,, F. Iannelli,, and G. Pozzi. 2003. Pneumococcal zinc metalloproteinase ZmpC cleaves human matrix metalloproteinase 9 and is a virulence factor in experimental pneumonia. Mol. Microbiol. 49:795805.
59. Oggioni, M. R.,, and G. Pozzi. 2001. Comparative genomics for identification of clone-specific sequence blocks in Streptococcus pneumoniae. FEMS Microbiol. Lett. 200:137143.
60. Poland, G. A. 1999. The burden of pneumococcal disease: the role of conjugate vaccines. Vaccine 17:16741679.
61. Poulsen, K.,, J. Reinholdt,, C. Jespersgaard,, K. Boye,, T. A. Brown,, M. Hauge,, and M. Kilian. 1998. A comprehensive genetic study of streptococcal immunoglobulin A1 proteases: evidence for recombination within and between species. Infect. Immun. 66:181190.
62. Powley, L.,, J. Meeson,, and D. Greenwood. 1989. Tolerance to penicillin in streptococci of viridans group. J. Clin. Pathol. 42:7780.
63. Pozzi, G.,, M. R. Oggioni,, and A. Tomasz. 1989. DNA probe for identification of Streptococcus pneumoniae. J. Clin. Microbiol. 27:370372.
64. Ramirez, M.,, E. Severina,, and A. Tomasz. 1999. A high incidence of prophage carriage among natural isolates of Streptococcus pneumoniae. J. Bacteriol. 181:36183625.
65. Reichmann, P.,, A. Konig,, J. Linares,, F. Alcaide,, F. C. Tenover,, L. McDougal,, S. Swidsinski,, and R. Hakenbeck. 1997. A global gene pool for high-level cephalosporin resistance in commensal Streptococcus species and Streptococcus pneumoniae. J. Infect. Dis. 176:10011012.
66. Reichmann, P.,, E. Varon,, E. Gunther,, R. R. Reinert,, R. Luttiken,, A. Marton,, P. Geslin,, J. Wagner,, and R. Hakenbeck. 1995. Penicillin-resistant Streptococcus pneumoniae in Germany: genetic relationship to clones from other European countries. J. Med. Microbiol. 43:377385.
67. Rudolph, K. M.,, A. J. Parkinson,, C. M. Black,, and L. W. Mayer. 1993. Evaluation of polymerase chain reaction for diagnosis of pneumococcal pneumonia. J. Clin. Microbiol. 31:26612666.
68. Saruta, K.,, T. Matsunaga,, M. Kono,, S. Hoshina,, S. Kanemoto,, O. Sakai,, and K. Machida. 1997. Simultaneous detection of Streptococcus pneumoniae and Haemophilus influenzae by nested PCR amplification from cerebrospinal fluid samples. FEMS Immunol. Med. Microbiol. 19:151157.
69. Schlegel, L.,, J. M. Prostak,, C. Spicq,, G. Sissia,, A. Fremaux,, and P. Geslin. 1998. Presumptive tests and molecular hybridization for the identification of untypable strains of Streptococcus pneumoniae. Pathol. Biol. 46:459463. (In French.)
70. Scott, J. A.,, E. L. Marston,, A. J. Hall,, and K. Marsh. 2003. Diagnosis of pneumococcal pneumonia by psaA PCR analysis of lung aspirates from adult patients in Kenya. J. Clin. Microbiol. 41:25542559.
71. Sibold, C.,, J. Henrichsen,, A. Konig,, C. Martin,, L. Chalkley,, and R. Hakenbeck. 1994. Mosaic pbpX genes of major clones of penicillin-resistant Streptococcus pneumoniae have evolved from pbpX genes of a penicillinsensitive Streptococcus oralis. Mol. Microbiol. 12:10131023.
72. Teng, L. J.,, P. R. Hsueh,, J. C. Tsai,, P. W. Chen,, J. C. Hsu,, H. C. Lai,, C. N. Lee,, and S. W. Ho. 2002. groESL sequence determination, phylogenetic analysis, and species differentiation for viridans group streptococci. J. Clin Microbiol. 40:31723178.
73. Tong, H.,, X. Gao,, and X. Dong. 2003. Streptococcus oligofermentans sp. nov., a novel oral isolate from caries-free humans. Int. J. Syst. Evol. Microbiol. 53:11011104.
74. Ubukata, K.,, Y. Asahi,, A. Yamane,, and M. Konno. 1996. Combinational detection of autolysin and penicillin-binding protein 2B genes of Streptococcus pneumoniae by PCR. J. Clin. Microbiol. 34:592596.
75. van Haeften, R.,, S. Palladino,, I. Kay,, T. Keil,, C. Heath,, and G. W. Waterer. 2003. A quantitative LightCycler PCR to detect Streptococcus pneumoniae in blood and CSF. Diagn. Microbiol. Infect. Dis. 47:407414.
76. Veenhoven, R.,, D. Bogaert,, C. Uiterwaal,, C. Brouwer,, H. Kiezebrink,, J. Bruin,, I. J. E,, P. Hermans,, R. de Groot,, B. Zegers,, W. Kuis,, G. Rijkers,, A. Schilder,, and E. Sanders. 2003. Effect of conjugate pneumococcal vaccine followed by polysaccharide pneumococcal vaccine on recurrent acute otitis media: a randomised study. Lancet 361:21892195.
77. Verhelst, R.,, T. Kaijalainen,, T. De Baere,, G. Verschraegen,, G. Claeys,, L. Van Simaey,, C. De Ganck,, and M. Vaneechoutte. 2003. Comparison of five genotypic techniques for identification of optochin-resistant pneumococcus-like isolates. J. Clin. Microbiol. 41:35213525.
78. Waite, R. D.,, D. W. Penfold,, J. K. Struthers,, and C. G. Dowson. 2003. Spontaneous sequence duplications within capsule genes cap8E and tts control phase variation in Streptococcus pneumoniae serotypes 8 and 37. Microbiology 149:497504.
79. Waite, R. D.,, J. K. Struthers,, and C. G. Dowson. 2001. Spontaneous sequence duplication within an open reading frame of the pneumococcal type 3 capsule locus causes high-frequency phase variation. Mol. Microbiol. 42:12231232.
80. Walker, J. A.,, R. L. Allen,, P. Falmagne,, M. K. Johnson,, and G. J. Boulnois. 1987. Molecular cloning, characterization, and complete nucleotide sequence of the gene for pneumolysin, the sulfhydryl-activated toxin of Streptococcus pneumoniae. Infect. Immun. 55:11841189.
81. Wasilauskas, B. L.,, and K. D. Hampton. 1984. An analysis of Streptococcus pneumoniae identification using biochemical and serological procedures. Diagn. Microbiol. Infect. Dis. 2:301307.
82. Whatmore, A. M.,, V. A. Barcus,, and C. G. Dowson. 1999. Genetic diversity of the streptococcal competence (com) gene locus. J. Bacteriol. 181:31443154.
83. Whatmore, A. M.,, and C. G. Dowson. 1999. The autolysin-encoding gene (lytA) of Streptococcus pneumoniae displays restricted allelic variation despite localized recombination events with genes of pneumococcal bacteriophage encoding cell wall lytic enzymes. Infect. Immun. 67:45514556.
84. Whatmore, A. M.,, A. Efstratiou,, A. P. Pickerill,, K. Broughton,, G. Woodard,, D. Sturgeon,, R. George,, and C. G. Dowson. 2000. Genetic relationships between clinical isolates of Streptococcus pneumoniae, Streptococcus oralis, and Streptococcus mitis: characterization of “atypical” pneumococci and organisms allied to S. mitis harboring S. pneumoniae virulence factor-encoding genes. Infect. Immun. 68:13741382.
85. Whatmore, A. M.,, S. J. King,, N. C. Doherty,, D. Sturgeon,, N. Chanter,, and C. G. Dowson. 1999. Molecular characterization of equine isolates of Streptococcus pneumoniae: natural disruption of genes encoding the virulence factors pneumolysin and autolysin. Infect. Immun. 67:27762782.
86. Wheeler, J.,, R. Freeman,, M. Steward,, K. Henderson,, M. J. Lee,, N. H. Piggott,, G. J. Eltringham,, and A. Galloway. 1999. Detection of pneumolysin in sputum. J. Med. Microbiol. 48:863866.
87. Wuorimaa, T.,, and H. Kayhty. 2002. Current state of pneumococcal vaccines. Scand. J. Immunol. 56:111129.
88. Zhang, Y.,, D. J. Isaacman,, R. M. Wadowsky,, J. Rydquist-White,, J. C. Post,, and G. D. Ehrlich. 1995. Detection of Streptococcus pneumoniae in whole blood by PCR. J. Clin. Microbiol. 33:596601.

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