Clonal dissemination of invasive and colonizing clonal complex 1 of serotype VI group B Streptococcus in central Taiwan

Streptococcus agalactiae (group B streptococcus or GBS) is a commensal bacterium that can frequently behave as a pathogen, particularly in the neonatal period and in the elderly. The gut is a primary site of GBS colonization and a potential port of entry during neonatal infections caused by hypervirulent clonal complex 17 (CC17) strains. Here we studied the interactions between the prototypical CC17 BM110 strain and polarized enterocytes using the Caco-2 cell line. GBS could adhere to and invade these cells through their apical or basolateral surfaces. Basolateral invasion was considerably more efficient than apical invasion and predominated under conditions resulting in weakening of cell-to-cell junctions. Bacterial internalization occurred by a mechanism involving caveolae- and lipid raft-dependent endocytosis and actin re-organization, but not clathrin-dependent endocytosis. In the first steps of Caco-2 invasion, GBS colocalized with the early endocytic marker EEA-1, to later reside in acidic vacuoles. Taken together, these data suggest that CC17 GBS selectively adheres to the lateral surface of enterocytes from which it enters through caveolar lipid rafts using a classical, actin-dependent endocytic pathway. These data may be useful to develop alternative preventive strategies aimed at blocking GBS invasion of the intestinal barrier.

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Emergence of the First Levofloxacin-Resistant Strains of Streptococcus agalactiae Isolated in Italy

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05127-14 ◽

2015 ◽

Vol 59 (4) ◽

pp. 2466-2469 ◽

Cited By ~ 15

Author(s):

G. Piccinelli ◽

F. Gargiulo ◽

S. Corbellini ◽

G. Ravizzola ◽

C. Bonfanti ◽

...

Keyword(s):

Clonal Complex ◽

Group B Streptococcus ◽

Sequence Type ◽

Fluoroquinolone Resistance ◽

Topoisomerase Iv ◽

Double Mutation ◽

Unknown Significance ◽

Resistant Strains ◽

Group B ◽

High Level

ABSTRACTOf 901 group B streptococcus strains analyzed, 13 (1.4%) were resistant to levofloxacin (MICs of >32 μg/ml for seven isolates, 2 μg/ml for four isolates, and 1.5 μg/ml for four isolates). Mutations in the quinolone resistance-determining regions (QRDRs) of gyrase and topoisomerase IV were identified. A double mutation involving the Ser-81 change to Leu forgyrAand the Ser-79 change to Phe or to Tyr forparCwas linked to a high level of fluoroquinolone resistance. In addition, two other mutational positions inparCwere observed, resulting in an Asp-83-to-Tyr substitution and an Asp-83-to-Asn substitution. Different mutations were also observed ingyrB, with unknown significance. Most levofloxacin-resistant GBS strains were of serotype Ib and belonged to sequence type 19 (ST19) and clonal complex 19 (CC-19). Most of them exhibited theepsilongene.

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Associations between capsular serotype, multilocus sequence type, and macrolide resistance inStreptococcus agalactiaeisolates from Japanese infants with invasive infections

Epidemiology and Infection ◽

10.1017/s0950268813001647 ◽

2013 ◽

Vol 142 (4) ◽

pp. 812-819 ◽

Cited By ~ 32

Author(s):

M. MOROZUMI ◽

T. WAJIMA ◽

Y. KUWATA ◽

N. CHIBA ◽

K. SUNAOSHI ◽

...

Keyword(s):

Clonal Complex ◽

Vaccine Development ◽

Late Onset ◽

Group B Streptococcus ◽

Sequence Type ◽

Macrolide Resistance ◽

Invasive Infections ◽

Resistant Strains ◽

Group B ◽

Sequence Types

SUMMARYStreptococcus agalactiae(group B streptococcus; GBS) isolates (n = 150) from infants with invasive infections between 2006 and 2011 were analysed for capsular serotype, multilocus sequence type, and antibiotic susceptibility. In cases with late-onset disease (n = 115), primary meningitis was predominant (62·6%), but represented only 39·1% in cases with early-onset disease (n = 23). The most common serotype was III (58·7%), followed by Ia (21·3%) and Ib (12·7%). Sequence types (STs) of serotype III strains included ST17 (50·0%), ST19 (26·1%), ST335 (18·2%), ST27 (4·5%), and ST1 (1·1%). Predominant STs of serotypes Ia and Ib were ST23 (81·3%) and ST10 (84·2%), respectively. No penicillin-resistant strains were detected, but 22·0% of strains hadmef(A/E),erm(A), orerm(B) genes, which mediate macrolide resistance. A new ST335, possessing anmef(A/E) gene belonging to clonal complex 19 gradually increased in frequency. Improved prevention of invasive GBS infections in infants requires timely identification, and ultimately vaccine development.

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Clonal Complex 17 Group B Streptococcus strains causing invasive disease in neonates and adults originate from the same genetic pool

Scientific Reports ◽

10.1038/srep20047 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 20

Author(s):

Sarah Teatero ◽

Erin Ramoutar ◽

Allison McGeer ◽

Aimin Li ◽

Roberto G. Melano ◽

...

Keyword(s):

Clonal Complex ◽

Group B Streptococcus ◽

Invasive Disease ◽

Group B ◽

Genetic Pool

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Clustered Regularly Interspaced Short Palindromic Repeat Analysis of Clonal Complex 17 Serotype III Group B Streptococcus Strains Causing Neonatal Invasive Diseases

International Journal of Molecular Sciences ◽

10.3390/ijms222111626 ◽

2021 ◽

Vol 22 (21) ◽

pp. 11626

Author(s):

Jen-Fu Hsu ◽

Jang-Jih Lu ◽

Chih Lin ◽

Shih-Ming Chu ◽

Lee-Chung Lin ◽

...

Keyword(s):

Dna Sequences ◽

Clonal Complex ◽

Group B Streptococcus ◽

Clinical Manifestations ◽

Rflp Analysis ◽

Comparative Sequence Analysis ◽

Rflp Pattern ◽

Invasive Diseases ◽

Short Palindromic Repeat ◽

Group B

Group B Streptococcus (GBS) is an important pathogen of neonatal infections, and the clonal complex (CC)-17/serotype III GBS strain has emerged as the dominant strain. The clinical manifestations of CC17/III GBS sepsis may vary greatly but have not been well-investigated. A total of 103 CC17/III GBS isolates that caused neonatal invasive diseases were studied using a new approach based on clustered regularly interspaced short palindromic repeats (CRISPR) loci and restriction fragment length polymorphism (RFLP) analyses. All spacers of CRISPR loci were sequenced and analyzed with the clinical presentations. After CRISPR-RFLP analyses, a total of 11 different patterns were observed among the 103 CRISPR-positive GBS isolates. GBS isolates with the same RFLP patterns were found to have highly comparable spacer contents. Comparative sequence analysis of the CRISPR1 spacer content revealed that it is highly diverse and consistent with the dynamics of this system. A total of 29 of 43 (67.4%) spacers displayed homology to reported phage and plasmid DNA sequences. In addition, all CC17/III GBS isolates could be categorized into three subgroups based on the CRISPR-RFLP patterns and eBURST analysis. The CC17/III GBS isolates with a specific CRISPR-RFLP pattern were more significantly associated with occurrences of severe sepsis (57.1% vs. 29.3%, p = 0.012) and meningitis (50.0% vs. 20.8%, p = 0.009) than GBS isolates with RFLP lengths between 1000 and 1300 bp. Whole-genome sequencing was also performed to verify the differences between CC17/III GBS isolates with different CRISPR-RFLP patterns. We concluded that the CRISPR-RFLP analysis is potentially applicable to categorizing CC17/III GBS isolates, and a specific CRISPR-RFLP pattern could be used as a new biomarker to predict meningitis and illness severity after further verification.

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