title: Identification and molecular characterization of a S. agalactiae strain lacking the capsular locus.
abstract: During a national surveillance program on Group B streptococci (GBS) maternal carriage and neonatal infections, a GBS strain isolated from a pregnant woman's vagino-rectal swab was non typable by either serological or molecular methods. Further molecular characterization demonstrated that the strain lacked the entire capsular locus, possibly by a recombination event that excised a 14,1 Kbase pairs genomic fragment extending from the regulatory protein cpsX gene to the neuA gene. The natural loss of the capsular locus by GBS isolated from a human has never been described so far. Such an event, while possibly a dead-end from the evolutionary point of view, leaves a still able-to-colonize organism unrecognizable by the vaccines currently under development.
authors: Reparto di Malattie Batteriche Respiratorie e Sistemiche-Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161, Rome, Italy. roberta.creti@iss.it
authors: R
authors: R
authors: Creti
authors: M
authors: M
authors: Imperi
authors: M
authors: M
authors: Pataracchia
authors: G
authors: G
authors: Alfarone
authors: S
authors: S
authors: Recchia
authors: L
authors: L
authors: Baldassarri
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