title: Comparison of transformation frequencies among selected Streptococcus pneumoniae serotypes.
abstract: Although there are over 90 serotypes of Streptococcus pneumoniae, antimicrobial resistance is predominantly found in a limited number of serotypes/serogroups, namely 6, 9, 14, 19 and 23. There is no compelling mechanism to account for this restriction. We aimed to determine whether serotypes commonly associated with drug resistance have higher transformation frequencies than those that are susceptible to antimicrobial agents. An in vitro investigation of the genetic transformation frequency of drug-resistant serotypes compared with that of susceptible serotypes under the influence of synthetic competence-stimulating peptides was performed. The transforming DNA was genomic DNA carrying a Tn916-like transposon containing the mefE gene that confers resistance to erythromycin. It was observed that serotypes 6, 9, 14, 19 and 23, which are highly associated with drug resistance, do not exhibit a higher degree of transformation efficiency than other serotypes. These findings suggest that the association of serotype with drug resistance is likely due to prolonged exposure to transforming DNA resulting from longer nasopharyngeal carriage and to a greater selective pressure from antimicrobials, particularly in children. This is the first study to compare the transformation frequencies of pneumococcal clinical isolates using genomic DNA that carries the composite Tn916-like element.
authors.affiliation: Department of Medical Microbiology, Makerere University College of Health Sciences, Upper Mulago Hill Road, PO Box 7072, Kampala, Uganda. moses.joloba@case.edu
authors.forename: Moses L
authors.initials: ML
authors.lastname: Joloba
authors.forename: Benson R
authors.initials: BR
authors.lastname: Kidenya
authors.forename: David P
authors.initials: DP
authors.lastname: Kateete
authors.forename: Fred A
authors.initials: FA
authors.lastname: Katabazi
authors.forename: Julian K
authors.initials: JK
authors.lastname: Muwanguzi
authors.forename: Benon B
authors.initials: BB
authors.lastname: Asiimwe
authors.forename: Simon P
authors.initials: SP
authors.lastname: Alarakol
authors.forename: Jessica L
authors.initials: JL
authors.lastname: Nakavuma
authors.forename: Saralee
authors.initials: S
authors.lastname: Bajaksouzian
authors.forename: Anne
authors.initials: A
authors.lastname: Windau
authors.forename: Michael R
authors.initials: MR
authors.lastname: Jacobs
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D004251:DNA Transposable Elements / Q000235:genetics; D004269:DNA, Bacterial; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D004917:Erythromycin / Q000494:pharmacology; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics; D008826:Microbial Sensitivity Tests; D011008:Pneumococcal Infections / Q000382:microbiology*; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000187:drug effects / Q000235:genetics*; D014170:Transformation, Genetic
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; C431304:MefE protein, Streptococcus pneumoniae; D008565:Membrane Proteins; D004917:Erythromycin
references.citation: Emerg Infect Dis. 2006 Nov;12(11):1709-14
references.pmid: 17283621
references.citation: Jpn J Infect Dis. 2006 Oct;59(5):299-05
references.pmid: 17060695
references.citation: Soc Appl Bacteriol Symp Ser. 1997;26:32S-41S
references.pmid: 9436315
references.citation: Microbiology (Reading). 1998 Nov;144 ( Pt 11):3061-3068
references.pmid: 9846741
references.citation: Paediatr Respir Rev. 2006 Sep;7(3):209-14
references.pmid: 16938644
references.citation: Diagn Microbiol Infect Dis. 2004 May;49(1):47-52
references.pmid: 15135500
references.citation: Antimicrob Agents Chemother. 2005 Jul;49(7):2903-13
references.pmid: 15980367
references.citation: Antimicrob Agents Chemother. 2004 Sep;48(9):3462-7
references.pmid: 15328112
references.citation: Antimicrob Agents Chemother. 2000 Dec;44(12):3395-401
references.pmid: 11083646
references.citation: Antimicrob Agents Chemother. 2005 Apr;49(4):1591-2
references.pmid: 15793147
references.citation: Antimicrob Agents Chemother. 2005 Oct;49(10):4180-4
references.pmid: 16189096
references.citation: Trends Microbiol. 1994 Oct;2(10):361-6
references.pmid: 7850202
references.citation: J Clin Microbiol. 2008 Mar;46(3):982-90
references.pmid: 18234877
references.citation: Lancet. 1977 Nov 12;2(8046):995-7
references.pmid: 72950
references.citation: Nat Rev Microbiol. 2008 Apr;6(4):288-301
references.pmid: 18340341
references.citation: N Engl J Med. 2002 Feb 21;346(8):630-1
references.pmid: 11856810
references.citation: Microb Drug Resist. 1997 Spring;3(1):27-37
references.pmid: 9109094
references.citation: Clin Vaccine Immunol. 2008 Feb;15(2):203-7
references.pmid: 18077618
references.citation: J Bacteriol. 2006 Mar;188(5):1744-9
references.pmid: 16484185
references.citation: Infect Immun. 1999 Jul;67(7):3690-2
references.pmid: 10377162
references.citation: N Engl J Med. 1994 Apr 28;330(17):1247-51
references.pmid: 8139650
references.citation: Antimicrob Agents Chemother. 2009 Mar;53(3):1293-4
references.pmid: 19104015
references.citation: J Clin Microbiol. 2010 Apr;48(4):1291-6
references.pmid: 20107087
references.citation: J Med Microbiol. 2004 Nov;53(Pt 11):1101-1103
references.pmid: 15496387
references.citation: N Engl J Med. 1978 Oct 5;299(14):735-40
references.pmid: 29219
references.citation: Diagn Microbiol Infect Dis. 2005 Mar;51(3):195-200
references.pmid: 15766606
references.citation: J Antimicrob Chemother. 1991 Sep;28(3):463-5
references.pmid: 1960128
references.citation: J Bacteriol. 2004 Jun;186(11):3447-52
references.pmid: 15150231
references.citation: Lancet. 2001 Mar 24;357(9260):950-2
references.pmid: 11289365
references.citation: Vaccine. 2004 Jun 2;22(17-18):2209-20
references.pmid: 15149779
references.citation: Int J Infect Dis. 2006 Nov;10(6):458-64
references.pmid: 16997591
references.citation: Clin Infect Dis. 2002 Jul 15;35(2):205-8
references.pmid: 12087529
references.citation: Mol Microbiol. 2001 May;40(3):555-71
references.pmid: 11359563
references.citation: J Infect. 2004 Jan;48(1):39-55
references.pmid: 14667791
references.citation: J Bacteriol. 1996 Oct;178(20):6087-90
references.pmid: 8830714