Recently, 2 serologically and biochemically distinct subtypes—11Aα 11Aβ—were discovered among serotype 11A isolates of Streptococcus pneumoniae. Sequence comparison the capsular polysaccharide synthesis (cps) loci subtypes identified disruption wcjE gene, a putative O-acetyltransferase, as genetic hallmark 11Aβ phenotype. Directed in vitro an 11Aα strain switched to phenotype, confirming role played by gene divergence between subtypes. Furthermore, sequences from 7 clinical strains each...

The polysaccharide (PS) capsule is essential for immune evasion and virulence of Streptococcus pneumoniae. Existing pneumococcal vaccines are designed to elicit anticapsule antibodies; however, the effectiveness these being challenged by emergence new types or variants. Herein, we characterize a newly discovered type, 33E, that appears have repeatedly emerged from vaccine type 33F via an inactivation mutation in glycosyltransferase gene, wciE. Structural analysis demonstrated 33E share...

Streptococcus pneumoniae can produce a wide breadth of antigenically diverse capsule types, fact that poses looming threat to the success vaccines target pneumococcal polysaccharide (PS) capsule. Yet, many types remain undiscovered and/or uncharacterized. Prior sequence analysis synthesis (

ABSTRACT Despite the emerging impact of serogroup 11 serotypes in Streptococcus pneumoniae epidemiology, structures capsule types have not been fully elucidated, particularly locations O -acetyl substitutions. Here, we report complete serotype 11B, 11C, and 11F polysaccharides a revision to 11A capsular polysaccharide using nuclear magnetic resonance (NMR). All shared linear, tetrasaccharide backbone with pendant phosphopolyalcohol. Three four saccharides are conserved all serotypes. The...

Abstract Background Due to elevated genetic divergence between different Carbapenem-resistant (CR) A. baumannii (Ab) lineages, CRAb isolates belonging clonal groups (CGs) currently emerging in the U.S. may display traits that differ from those of unrelated international CGs. Variations CG-associated physiology could especially affect choice and interpretation antimicrobial susceptibility tests (AST) for these multidrug resistant lineages. Methods We integrated multimodal AST comparative...

Abstract Introduction Treatment of infections in patients with burn injuries is challenging due to altered antimicrobial pharmacokinetics. Continuous infusion β‐lactam therapy may be a useful stewardship strategy improve pharmacodynamic target attainment this population. Case Summaries This report highlights the use continuous ceftolozane/tazobactam (C/T) two extensive total body surface area (TBSA) burns, suspected augmented renal clearance (ARC), and bloodstream caused by Pseudomonas...

A survey of nasopharyngeal carriage penicillin nonsusceptible pneumococcal (PNSp) isolates was conducted among 1192 children attending 62 day care centers in Brazil, where vaccination has not been routinely introduced. Nasopharyngeal detected 686 (57.6%) infants, and 178 (25.9%) them carried PNSp isolates. Being less than 24 months age, hospitalization the previous 3 months, recurrent acute otitis media were independently associated with PNSp. Serotypes 14, 23F, 19A, 6A, 6B 19F most common...

ABSTRACT Streptococcus pneumoniae is a significant bacterial pathogen that expresses >90 capsule serotypes. Conventional serotyping methods assume each serotype genetically and antigenically distinct entity; however, recent investigations have revealed pneumococcal isolates cannot be unambiguously serotyped because they share the properties of more than one serotype. Here, we employed novel method NMR spectroscopy to examine clinical sharing serotypes 11A 11E. These ambiguous were...

Background. Streptococcus pneumoniae is a significant pathogen capable of expressing protective and antigenically diverse capsules. To better understand the molecular basis capsular antigenic diversity, we investigated hypothetical serological role wcjE, which encodes capsule O-acetyltransferase, in vaccine-targeted serotype 9V related 9A.

Reports conflict regarding which lectin-microbial ligand interactions elicit a protective response from the lectin pathway (LP) of complement. Using fluorescent microscopy, we demonstrate human ficolin-2 binds to Streptococcus pneumoniae serotype 11A capsule polysaccharide dependent on O-acetyltransferase gene wcjE. This triggers complement deposition and promotes opsonophagocytosis encapsulated pneumococci. Even partial loss expression through wcjE mutation abrogated bacterial killing....

The ongoing injection drug use (IDU) crisis in the United States has been complicated by an emerging epidemic of Staphylococcus aureus IDU-associated bloodstream infections (IDU-BSI).We performed a case-control study comparing S. IDU-BSI and non-IDU BSI cases identified large US Midwestern academic medical center between Jan 1, 2016 Dec 21, 2019. We obtained whole-genome sequences 154 91 cases, which were matched with clinical data. phylogenetic comparative genomic analyses to investigate...

Abstract Temporal analysis of Acinetobacter calcoaceticus-baumannii complex isolates in a large, US healthcare system demonstrated decreased occurrence antibiotic-susceptible between November and May, while resistant isolate was temporally stable. This resulted 50%–100% seasonal increases resistance rates. work offers insight into the phenomenon Gram-negative pathogen seasonality.

Eliminating carbapenem-resistant Acinetobacter baumannii (CRAb) disease requires comprehensive knowledge of how this noncommensal organism propagates among at-risk hosts. We molecularly characterized an ongoing surge CRAb cases patients in a Midwest US healthcare system, which coincided with sustained reductions hospital-acquired infections and falloffs associated distinctly more resistant antibiotypes. Genome sequencing revealed isolates belonged to emergent Pasteur scheme sequence type 499...

We retrospectively compared the clinical characteristics of hospital-acquired (HA) vs non-hospital-acquired (nHA) Acinetobacter calcoaceticus-baumannii complex isolates in a large health care system St. Louis, Missouri, from 2007 to 2017. More than 60% total were nHA; they predominantly nonrespiratory sources and exhibited ~40% carbapenem resistance rates stably persisted, though HA occurrence waned.

Abstract Acinetobacter baumannii ( Ab ) disease in the U.S. is commonly attributed to outbreaks of one or two monophyletic carbapenem resistance (CR) lineages that vary by region. However, there limited knowledge regarding epidemiology and population structure Deep South, few studies compare contemporary CR carbapenem-susceptible (Cs) , despite prevalence latter. We performed a 12-year time series analysis cases large hospital Birmingham, AL, 89 isolates from an ongoing surveillance project...

Abstract Background Acinetobacter baumannii (Ab) disease in the United States is commonly attributed to outbreaks of 1 or 2 monophyletic carbapenem resistance (CR) Ab lineages that vary by region. However, there limited knowledge regarding CRAb epidemiology and population structures U.S. Deep South, few studies compare contemporary CR carbapenem-susceptible (Cs) Ab, despite relative prevalence latter. Methods We performed a multiyear analysis 2462 cases large healthcare system Birmingham,...

ABSTRACT A multiplexed opsonophagocytosis assay (MOPA) was developed as a cost-effective, high-throughput biological to evaluate the efficacy of pneumococcal vaccines by in vitro measurement opsonophagocytic activity anti-capsular antibodies. Here, we report draft genomes 36 strains Streptococcus pneumoniae for use reference MOPA.

Abstract Background Acinetobacter baumannii ( Ab ) is a global health threat notorious for causing hospital-acquired (HA) infections, though many infections are community-acquired (CA). Investigations describing contemporaneous, clinically-relevant CA and HA populations, lacking. Methods We conducted retrospective ecological analysis of 2042 clinical isolates identified from 2007 to 2017 in the BJC HealthCare System (BJC), multi-hospital system located around greater metropolitan area St....