The newly described species has been cultured from the upper respiratory tract of humans and appears to have little pathogenic potential. The species encodes a capsular biosynthesis locus of approximately 12 kb composed of three distinct regions. Region I and III genes, involved in export and processing of the capsular material, show high similarity to the corresponding genes in capsulate lineages of the pathogenic species ; indeed, standard and PCRs for detection of capsulated strains of give positive results with strains of . Three ORFs are present in region II of the sequenced strain of , of which a putative phosphotransferase showed homology with corresponding genes from serotype c and f. Phylogenetic analysis of housekeeping genes from 24 species showed that was only distantly related to . In contrast to , the capsule locus in is not associated with transposases or other transposable elements. Our data suggest that the capsule locus of capsulate lineages of may have been recruited relatively recently from the commensal species by horizontal gene transfer.


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