J Med Microbiol Email Content Delivery
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplementary data
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Kong, F.
Right arrow Articles by Gilbert, G. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kong, F.
Right arrow Articles by Gilbert, G. L.
Agricola
Right arrow Articles by Kong, F.
Right arrow Articles by Gilbert, G. L.
J Med Microbiol 55 (2006), 829-837; DOI: 10.1099/jmm.0.46307-0
© 2006 Society for General Microbiology
ISSN 1473-5644

Streptococcus agalactiae Cß protein gene (bac) sequence types, based on the repeated region of the cell-wall-spanning domain: relationship to virulence and a proposed standardized nomenclature

Fanrong Kong1, Heather F. Gidding1, Reinhard Berner2 and Gwendolyn L. Gilbert1

1 Centre for Infectious Diseases and Microbiology (CIDM), Institute of Clinical Pathology and Medical Research (ICPMR), Westmead Hospital, Darcy Road, Westmead, New South Wales 2145, Australia

2 Department of Pediatrics, University Children's Hospital, D-79106 Freiburg, Germany

Correspondence
Gwendolyn L. Gilbert
lyng{at}icpmr.wsahs.nsw.gov.au

Received 26 August 2005
Accepted 9 March 2006

The Cß protein (Bac) of Streptococcus agalactiae (group B streptococcus; GBS) is an IgA binding protein encoded by bac, of which at least 39 sequence types have been described, based on polymorphisms in the repeated region of the cell-wall-spanning domain (‘bac sequence types’). Cß is usually found in serotype Ib, less commonly in serotype II, and rarely in other serotypes. The aim of this study was to examine the prevalence, variety and distribution, among GBS serotypes and between invasive and superficial isolates, of bac sequence types. A total of 1101 GBS isolates were tested, from 10 countries, with a bac-specific PCR, and amplicons from all 255 (23 %) with positive results were sequenced. Ninety-seven percent (184/190) of serotype Ib and 37 % of serotype II isolates were bac positive. The C{alpha} protein gene (bca) was present in 98 % (251/255), and insertion sequences IS1381 and IS861 in 94 % (239/255), of bac-positive isolates. The authors identified 59 bac sequence types belonging to 19 groups, based on length, from 496 to 946 bp, with up to six sequence variants (a–f) in each group. The median bac sequence length of invasive isolates was significantly shorter than that of superficial isolates overall (640 versus 586 bp; P <0.001) and specifically for serotype Ib (541 versus 676 bp; P <0.001), and invasive isolates were significantly (P <0.001) more likely to have one or more 18 bp deletions relative to the original published bac sequence (X59771). bac sequence typing is a useful addition to the previously described genotyping system, and will help to predict relative virulence among S. agalactiae serotype Ib strains.

Abbreviations: GBS, group B streptococcus; mge, mobile genetic element; MS, molecular serotype; pgp, protein gene profile.

The GenBank/EMBL/DDBJ accession numbers for the bac sequences determined in this study are AY672137–AY672167.

A phylogenetic tree inferred from 59 partial bac sequence types is available in Supplementary Fig. S1 with the online version of this paper.




This article has been cited by other articles:


Home page
 CVIHome page
H.-H. Yang, S. J. Mascuch, L. C. Madoff, and L. C. Paoletti
Recombinant Group B Streptococcus Alpha-Like Protein 3 Is an Effective Immunogen and Carrier Protein
Clin. Vaccine Immunol., July 1, 2008; 15(7): 1035 - 1041.
[Abstract] [Full Text] [PDF]

Home page
 J. Clin. Microbiol.Home page
H.-C. Slotved, F. Kong, L. Lambertsen, S. Sauer, and G. L. Gilbert
Serotype IX, a Proposed New Streptococcus agalactiae Serotype
J. Clin. Microbiol., September 1, 2007; 45(9): 2929 - 2936.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
INT J SYST EVOL MICROBIOL J MED MICROBIOL MICROBIOLOGY J GEN VIROL ALL SGM JOURNALS
Copyright © 2006 Society for General Microbiology.