The adaptive potential during nasopharyngeal colonisation of Streptococcus pneumoniae.

摘要: Abstract Adaptation to host defences and antimicrobials is critical for Streptococcus pneumoniae (the pneumococcus) during colonisation of the nasopharynx – its only ecological habitat. The pneumococcus highly transformable with genome between different strains varying widely in both gene content sequence. Thus, mixed colonising together will expand genetic reservoir “supragenome” this microorganism, increasing adaptive potential. extent phenotypic genotypic diversity co-colonising was determined. In contrast most carriage studies, which characterise single colonies, a systematic analysis up 20 colonies per undertaken Tanzanian children 12 months. serotype determined by conventional serology confirmed DNA-based methods. antibiotype penicillin co-trimoxazole from minimum inhibitory concentration E -test. As representative genotype sequence types (STs) multilocus typing (MLST). Of 61 events studied, seven (11.5%) had expressing multiple serotypes, maximum five serotypes detected. Four also co-colonisation and/or susceptible non-susceptible pneumococci. Sequence revealed that 58% were unique our cohort. Simultaneous six STs two 6B seen. Re-isolation either same or Genetically related single-locus double-locus variants identified cohort differed nucleotides. Multiple colony characterisation evidence microevolution greater pneumococcal than previously observed, thus potential adapt response environment colonisation.