Characterisation of invasive group B streptococci based on investigation of surface proteins and genes encoding surface proteins

• Published in: Clinical microbiology and infection Vol. 14; no. 1; pp. 66 - 73
• Main Authors: Persson, E., Berg, S., Bevanger, L., Bergh, K., Valsö-Lyng, R., Trollfors, B.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Elsevier Ltd 01.01.2008; Blackwell Publishing Ltd; Blackwell
• Subjects: 80 and over; Adult; Aged; Aged, 80 and over; analysis; Bacterial diseases; Bacterial Proteins; Bacterial Proteins - analysis; Bacterial Proteins - genetics; Biological and medical sciences; chemistry; Female; genetics; Genotype; group B streptococcus; Human bacterial diseases; Humans; Immunoassay; Immunoassay - methods; Infant; Infant, Newborn; Infectious diseases; isolation & purification; Male; Medical sciences; Membrane Proteins; Membrane Proteins - analysis; Membrane Proteins - genetics; methods; microbiology; Microbiology in the medical area; Middle Aged; Mikrobiologi inom det medicinska området; Newborn; Polymerase Chain Reaction; Polymerase Chain Reaction - methods; serotype; Staphylococcal infections, streptococcal infections, pneumococcal infections; Streptococcal Infections; Streptococcal Infections - microbiology; Streptococcus agalactiae; Streptococcus agalactiae - chemistry; Streptococcus agalactiae - genetics; Streptococcus agalactiae - isolation & purification; surface protein; Sweden; vaccine candidates; Sweden; group B streptococcus; Genotype; vaccine candidates; Streptococcus agalactiae; serotype; surface protein; Typing; Vaccine; Protein; Infection; Prevention; Streptococcaceae; Immunoprophylaxis; Microbiological investigation; Streptococcal infection; Streptococcus B; Bacteriosis; Bacteria; Micrococcales; Serotype
• ISSN: 1198-743X; 1469-0691
• DOI: 10.1111/j.1469-0691.2007.01877.x

The joint distributions of the six genes bca, bac, ɛ/alp1, alp2, alp3 and rib (encoding α-C-protein, β-C-protein, ɛ/Alp1, Alp2, Alp3, and Rib, respectively) and the proteins α-C-protein, β-C-protein and Rib were investigated in invasive isolates of group B streptococcus (GBS). In total, 297 invasive isolates (123 from neonates, 174 from adults) from south-west Sweden were collected during a 13-year period. Genes were detected using multiplex and specific PCRs, and expression of the surface proteins was demonstrated using monoclonal antibodies. The genes studied were found alone or in combinations in 294 (99%) of the invasive isolates. The most common genes were rib (n = 127 isolates, 43%), alp3 (n = 78, 26%) and ɛ/alp1 (n = 42, 14%). The bac gene was never found alone, but was found in combination with one other gene in 36 isolates. The surface proteins studied were detected alone or in combinations in 152 (51%) isolates, with the most common being Rib (n = 80, 27%), α-C-protein (n = 68, 23%) and β-C-protein (n = 24, 8%). Several genes were associated significantly with particular serotypes (e.g., ɛ/alp1 with serotype Ia; bca and bac with serotypes Ib and II; rib with serotype III; alp3 with serotype V). Overall, it was concluded that demonstration of different genes and surface proteins of GBS strains can be useful in epidemiological studies and in formulation of vaccines, but disappointingly, no single gene or surface protein included in the study was sufficiently common for it to be considered as the basis for a successful GBS vaccine.