scholarly journals The basic keratin 10-binding domain of the virulence-associated pneumococcal serine-rich protein PsrP adopts a novel MSCRAMM fold

Open Biology ◽  
2014 ◽  
Vol 4 (1) ◽  
pp. 130090 ◽  
Author(s):  
Tim Schulte ◽  
Jonas Löfling ◽  
Cecilia Mikaelsson ◽  
Alexey Kikhney ◽  
Karina Hentrich ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Invasive Disease ◽  
Binding Domain ◽  
Upper Respiratory Tract ◽  
Binding Region ◽  
Sequence Identity ◽  
Novel Variant ◽  
Upper Respiratory ◽  
Β Sheet ◽  
Specific Virulence

Streptococcus pneumoniae is a major human pathogen, and a leading cause of disease and death worldwide. Pneumococcal invasive disease is triggered by initial asymptomatic colonization of the human upper respiratory tract. The pneumococcal serine-rich repeat protein (PsrP) is a lung-specific virulence factor whose functional binding region (BR) binds to keratin-10 (KRT10) and promotes pneumococcal biofilm formation through self-oligomerization. We present the crystal structure of the KRT10-binding domain of PsrP (BR 187–385 ) determined to 2.0 Å resolution. BR 187–385 adopts a novel variant of the DEv-IgG fold, typical for microbial surface components recognizing adhesive matrix molecules adhesins, despite very low sequence identity. An extended β-sheet on one side of the compressed, two-sided barrel presents a basic groove that possibly binds to the acidic helical rod domain of KRT10. Our study also demonstrates the importance of the other side of the barrel, formed by extensive well-ordered loops and stabilized by short β-strands, for interaction with KRT10.

scholarly journals Silent Mastoiditis Associated with Pneumococcal Meningitis

2021 ◽  
Vol 27 (2) ◽  
pp. 1-6
Author(s):  
Ashikin Mohd Nordin ◽  
Jean Jun Ong ◽  
Juriza Ismail ◽  
Norazlin Kamal Nor ◽  
Sau Wei Wong ◽  
...  
Keyword(s):  
Brain Imaging ◽  
Pneumococcal Meningitis ◽  
Wide Spectrum ◽  
Clinical Signs ◽  
Invasive Disease ◽  
Upper Respiratory Tract ◽  
Slow Recovery ◽  
Acute Mastoiditis ◽  
Focus Of Infection ◽  
Upper Respiratory

Streptococcus pneumoniae (S pneumoniae) can cause a wide spectrum of diseases which includes upper respiratory tract infection as well as more severe invasive disease such as meningitis. Meningitis may be caused by invasion of the organism through the blood brain barrier, either via haematological spread or from an adjacent focus of infection such as the ears. We describe two infants with pneumococcal meningitis and silent mastoiditis. They both presented with a classical history to suggest meningitis with no apparent focus of infection. A brain imaging was done in the first infant to look for the underlying cause of his focal seizure and in the second infant, to assess for complications of meningitis, as he had a slow recovery. While they did not have any clinical signs to point towards the diagnosis, they were both diagnosed to have acute mastoiditis from brain imaging. We would like to highlight the importance of brain imaging in excluding silent mastoiditis in infants with meningitis, particularly in those whose clinical course appears atypical.

A Potential Benefit of Hypochlorous Acid - Facial Sanitisation: A Review

2021 ◽  
Author(s):  
Avis Aman Nowbuth ◽  
Josh Barrie Armstrong ◽  
Thomas Eugene Cloete ◽  
Pieter Rousseau Fourie
Keyword(s):  
Respiratory Tract ◽  
Biofilm Formation ◽  
Respiratory Tract Infections ◽  
Microbial Contamination ◽  
Hypochlorous Acid ◽  
Skin Infections ◽  
Upper Respiratory Tract ◽  
The Face ◽  
Upper Respiratory ◽  
Tract Infections

Sanitisation has become a major component of everyday life, with emphasis on the hands and surfaces. The face remains unsanitised due to the lack of an acceptable sanitiser. The use of masks has been mandated to reduce the spread of the pathogens by covering the face, however, there remain issues with the use of personal protective equipment. The face remains a harbour for upper respiratory tract infections, with constant deposition of microbes. By reducing microbial load, the risk of both infection and severity are reduced. HOCl has proven antimicrobial and anti-inflammatory activity, including efficacy against SARS-CoV-2. A facial sanitiser, alongside hand sanitisers and masks, improves protection against SARS-CoV-2. The advantages of regular sanitising of the face and mask include reduced level of microbial contamination, risk of biofilm formation, and respiratory tract and skin infections. HOCl was reviewed as a face and mask sanitiser, concluding that it was an ideal product.

scholarly journals Variation in the Presence of Neuraminidase Genes among Streptococcus pneumoniae Isolates with Identical Sequence Types

2006 ◽  
Vol 74 (6) ◽  
pp. 3360-3365 ◽  
Author(s):  
Melinda M. Pettigrew ◽  
Kristopher P. Fennie ◽  
Matthew P. York ◽  
Janeen Daniels ◽  
Faryal Ghaffar
Keyword(s):  
Streptococcus Pneumoniae ◽  
Young Children ◽  
Invasive Disease ◽  
Virulence Determinants ◽  
Upper Respiratory Tract ◽  
Capsule Type ◽  
Virulence Potential ◽  
The Relationship ◽  
Sequence Types ◽  
Specific Virulence

ABSTRACT Streptococcus pneumoniae frequently colonizes the upper respiratory tract of young children and is an important cause of otitis media and invasive disease. Carriage is more common than disease, yet the genetic factors that predispose a given clone for disease are not known. The relationship between capsule type, genetic background, and virulence is complex, and important questions remain regarding how pneumococcal clones differ in their ability to cause disease. Pneumococcal neuraminidase cleaves sialic acid-containing substrates and is thought to be important for pneumococcal virulence. We describe the distribution of multilocus sequence types (ST), capsule type, and neuraminidase genes among 342 carriage, middle ear, blood, and cerebrospinal fluid (CSF) pneumococcal strains from young children. We found 149 STs among our S. pneumoniae isolates. nanA was present in all strains, while nanB and nanC were present in 96% and 51% of isolates, respectively. The distribution of nanC varied among the strain collections from different tissue sources (P = 0.03). The prevalence of nanC was 1.41 (95% confidence interval, 1.11, 1.79) times higher among CSF isolates than among carriage isolates. We identified isolates of the same ST that differed in the presence of nanB and nanC. These studies demonstrate that virulence determinants, other than capsule loci, vary among strains of identical ST. Our studies suggest that the presence of nanC may be important for tissue-specific virulence. Studies that both incorporate MLST and take into account additional virulence determinants will provide a greater understanding of the pneumococcal virulence potential.

scholarly journals A Potential Benefit of Hypochlorous Acid - Facial Sanitisation

2021 ◽  
Author(s):  
Avis Aman Nowbuth ◽  
Josh Barrie Armstrong ◽  
Thomas Eugene Cloete ◽  
Pieter Rousseau Fourie
Keyword(s):  
Respiratory Tract ◽  
Biofilm Formation ◽  
Respiratory Tract Infections ◽  
Microbial Contamination ◽  
Hypochlorous Acid ◽  
Skin Infections ◽  
Upper Respiratory Tract ◽  
The Face ◽  
Upper Respiratory ◽  
Tract Infections

Sanitisation has become a major component of everyday life, with emphasis on the hands and surfaces. The face remains unsanitised due to the lack of an acceptable sanitiser. The use of masks has been mandated to reduce the spread of the pathogens by covering the face, however, there remain issues with the use of personal protective equipment. The face remains a harbour for upper respiratory tract infections, with constant deposition of microbes. By reducing microbial load, the risk of both infection and severity are reduced. HOCl has proven antimicrobial and anti-inflammatory activity, including efficacy against SARS-CoV-2. A facial sanitiser, alongside hand sanitisers and masks, improves protection against SARS-CoV-2. The advantages of regular sanitising of the face and mask include reduced level of microbial contamination, risk of biofilm formation, and respiratory tract and skin infections. HOCl was reviewed as a face and mask sanitiser, concluding that it was an ideal product.

scholarly journals Increased Chain Length Promotes Pneumococcal Adherence and Colonization

2012 ◽  
Vol 80 (10) ◽  
pp. 3454-3459 ◽  
Author(s):  
Jesse L. Rodriguez ◽  
Ankur B. Dalia ◽  
Jeffrey N. Weiser
Keyword(s):  
Parental Strain ◽  
A549 Cells ◽  
Invasive Disease ◽  
Upper Respiratory Tract ◽  
Epithelial Surface ◽  
Content Type ◽  
Morphological Heterogeneity ◽  
Upper Respiratory

ABSTRACTStreptococcus pneumoniaeis a mucosal pathogen that grows in chains of variable lengths. Short-chain forms are less likely to activate complement, and as a consequence they evade opsonophagocytic clearance more effectively during invasive disease. When grown in human nasal airway surface fluid, pneumococci exhibited both short- and long-chain forms. Here, we determined whether longer chains provide an advantage during colonization when the organism is attached to the epithelial surface. Chain-forming mutants and the parental strain grown under conditions to promote chain formation showed increased adherence to human epithelial cells (A549 cells)in vitro. Additionally, adherence to A549 cells selected for longer chains within the wild-type strain.In vivoin a murine model of colonization, chain-forming mutants outcompeted the parental strain. Together, our results demonstrate that morphological heterogeneity in the pneumococcus may promote colonization of the upper respiratory tract by enhancing the ability of the organism to bind to the epithelial surface.

scholarly journals IdentifyingStreptococcus pneumoniaegenes associated with invasive disease using pangenome-based whole genome sequence typing

2018 ◽  
Author(s):  
Uri Obolski ◽  
Andrea Gori ◽  
José Lourenço ◽  
Craig Thompson ◽  
Robin Thompson ◽  
...  
Keyword(s):  
Genome Sequence ◽  
Pneumococcal Disease ◽  
Learning Algorithm ◽  
Invasive Disease ◽  
Whole Genome Sequence ◽  
Data Sets ◽  
Whole Genome ◽  
Upper Respiratory Tract ◽  
Pneumococcal Carriage ◽  
Upper Respiratory

AbstractStreptococcus pneumoniaeis a normal commensal of the upper respiratory tract but can also invade the bloodstream or CSF (cerebrospinal fluid), causing invasive pneumococcal disease (IPD). In this study, we attempt to identify genes associated with IPD by applying a random forest machine-learning algorithm to whole genome sequence (WGS) data. We find 43 genes consistently associated with IPD across three geographically distinct WGS data sets of pneumococcal carriage isolates. Of these genes, 23 genes have previously shown to be directly relevant to IPD, while the other 18 are uncharacterized.

scholarly journals Epidemiology of Haemophilus parasuis isolates from pigs in China using serotyping, antimicrobial susceptibility, biofilm formation and ERIC-PCR genotyping

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5040 ◽  
Author(s):  
Yongda Zhao ◽  
Qin Wang ◽  
Jie Li ◽  
Xiaohuan Lin ◽  
Xianhui Huang ◽  
...  
Keyword(s):  
Antimicrobial Susceptibility ◽  
Biofilm Formation ◽  
High Morbidity ◽  
Haemophilus Parasuis ◽  
Upper Respiratory Tract ◽  
High Prevalence ◽  
Upper Respiratory ◽  
Polymerase Chain ◽  
High Degree ◽  
Lineage Diversity

Background Haemophilus parasuis is a commensal organism of the upper respiratory tract of healthy pigs and causes high morbidity and mortality in piglets. The aim of this study was to investigate the epidemiology of H. parasuis in China from 2014 to 2017. Methods We characterized 143 H. parasuis isolates by serotyping, antimicrobial susceptibility, biofilm formation and with enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) assays. Results Serotyping revealed serovar 5 as the most prevalent (26.6%) followed by serovars 4 (22.4%), 7 (9.1 %), 13 (6.3%), 12 (5.6 %), and non-typeable (8.4%). In a panel of 23 antimicrobials, the minimum inhibitory concentration 50% (MIC50) were in the range of 0.25–16 μg/mL and MIC90 were 2–>512 μg/mL. A total of 99 isolates of H. parasuis (69.2%) were able to form biofilms and 59.6% (59/99) performed weak biofilm-forming ability. ERIC-PCR revealed a very heterogeneous pattern with 87 clusters. Discussion These H. parasuis isolates showed a high serovar and genotypic lineage diversity, different abilities to form biofilms and a high degree of genetic diversity. Biofilm formation was related to antimicrobial susceptibility but there were no statistically significant associations between the antimicrobial susceptibility and either the serovars or the ERIC-PCR clusters. This study showed a high prevalence of high-MIC H. parasuis strains and suggests the need for a continuous surveillance of clinical isolates of H. parasuis.

Determination of capability of biofilm formation of strains s.aureus selected from the upper respiratory tract

2021 ◽  
Vol 43 (3-4) ◽  
pp. 42-45
Author(s):  
N. Y. Kravets ◽  
Keyword(s):  
Staphylococcus Aureus ◽  
Respiratory Tract ◽  
Biofilm Formation ◽  
Control Measures ◽  
Past Century ◽  
Upper Respiratory Tract ◽  
Chronic Infections ◽  
Inflammatory Lesions ◽  
Acute Infections ◽  
Upper Respiratory

Millions of people have died from acute infections in the past century, but they have been effectively fought through the development of modern vaccines, antibiotics and infection control measures. Chronic infections are slower than acute infections, and the symptoms are often vague, difficult, and sometimes impossible to cure with antibiotics. Important signs of chronic biofilm infections are extreme resistance to antibiotics and many other common antimicrobials, as well as the extraordinary ability to avoid the host’s defenses. One such disease is chronic inflammatory lesions of the tonsils, the main infectious agents of which are gram-positive cocci, strains Staphylococcus spp., Streptococcus spp. The purpose of the study of the ability of strains of Staphylococcus aureus to form a biofilm isolated from the surface of the epithelium of the upper respiratory tract of children. Clinical strains of Staphylococcus aureus bacteria obtained from the oropharynx of 32 children with tonsils affected by the inflammatory process at the age of 4-12 years (median – 7) were studied. The results of microbiological examination of biomaterial obtained from children with chronic inflammatory lesions of the tonsils showed that in 32 samples 25 strains of S. aureus were identified, 12 of them (48%) are capable of forming a biofilm, and 13 strains (52%) (not adhesive) are not had this ability. The study of the dynamics of biofilm formation by selected strains of S. aureus showed an increase in optical density (OS) during three days of cultivation, ranging from 0.143

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