Emergence of Neoteric Serotypes Among Multidrug Resistant Strains of Streptococcus pneumoniae Prevalent in Egypt

Bahy, Rehab; Hamouda, Hayam M.; Shahat, Amal S.; Yassin, Aymen S.; Amin, Magdy A.

doi:10.5812/jjm.30708

Cited by 9 publications

(7 citation statements)

References 32 publications

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“…Isolates were cultured and identified as S. pneumoniae , the serotyping of which revealed that the most common serotypes are 6A/B (30%) followed by 19F (28%), (Table 1) (Bahy et al, 2016). Consequently, the serotypes 6A/B and 19F were considered as the most predominant serotypes.…”

Section: Resultsmentioning

confidence: 99%

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Development and evaluation of a novel vaccine against prevalent invasive multi-drug resistant strains ofStreptococcus pneumoniae

Bahy

Hamouda

Shahat

et al. 2016

PeerJ

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Streptococcus pneumoniae is a pathogen that causes serious invasive infections, such as septicemia, meningitis and pneumonia in addition to mild upper respiratory tract infections. Protection from pneumococcal diseases is thought to be mediated mainly by serotype-specific antibodies to capsular antigens. Pneumococcal conjugate vaccine consists of sugars (polysaccharides) from the capsule of the bacterium S. pneumoniae that are conjugated to a carrier protein. Three pneumococcal conjugated vaccines, each directed against a group of serotypes, are registered in Egypt; however, local vaccine production is required to cover the most prevalent serotypes. In this work, capsular polysaccharide from the most current and prevalent serotypes in Egypt were extracted, purified and conjugated to bovine serum albumin (BSA). The polysaccharide protein conjugate was purified through ultrafiltration technique and molecular size distribution was compared to an available vaccine. The immunogenicity of the prepared vaccine was examined via two methods: First, by measuring the levels of the elicited antibodies in the sera of the vaccinated mice; second, by challenging the vaccinated groups of mice with approximately 107 CFU of each specific serotype and determining the degree of protection the developled vaccine offers. Our results show that the developed conjugated capsular polysaccharide vaccine is highly immunogenic and protective in mice. This finding illustrates the importance of tracking the most recent and predominant peneumococcal serotypes to generate effective vaccines, instead of using expensive imported vaccines with large number of serotypes which might not be even present in the community.

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Section: Resultsmentioning

confidence: 99%

“…In our recent work, it was found that currently the most predominant serotypes in Egypt are serotypes 6A/B and 19F of invasive S. pneumoniae which also showed alarming levels of multi drug resistance (Bahy et al, 2016). Both serotypes all together accounted for over 50% of the prevalent types.…”

Section: Introductionmentioning

confidence: 99%

Development and evaluation of a novel vaccine against prevalent invasive multi-drug resistant strains ofStreptococcus pneumoniae

Bahy

Hamouda

Shahat

et al. 2016

PeerJ

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“…The consistency of the ndings described with those available in the literature on speci c pathogens in the region leads to hypothesize that, despite the limitations above described, the concerning high proportion of AMR strains detected in this review has a certain degree of validity. * Articles can report antibiotic resistance profile on more than one pathogen, and therefore the sum of the articles in this table can differ from the total per Country detailed * Articles can report antibiotic resistance profile on more than one pathogen, and therefore the sum of the articles in this table can differ from the total per Country detailed ¶ Articles can describe results for more than one Country: in such case they are counted only once in the total (46,60,67,76,83,93,120,121,139,148,171)…”

Section: Limitationsmentioning

confidence: 99%

Antimicrobial resistance among GLASS pathogens in conflict and non-conflict affected settings in the Middle East: A systematic review

Truppa

Abo‐Shehada

2020

Preprint

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Background: In spite of the evident general negative effects of armed conflict on countries’ health systems and populations’ health outcomes, little is known about similar impacts of conflicts on the spread of antimicrobial resistances (AMR). This review was to address this evidence gap and describe:1. Patterns of AMR in the Middle East (ME) and resistance profiles of pathogens included in the Global AMR Surveillance System (GLASS) supported by the World Health Organization;2. Differences in proportions of AMR isolates between conflict and non-conflict countries. Methods: A systematic literature review was conducted following PRISMA guidelines and searching five electronic databases. Subject heading and free text were searched for “antimicrobial resistances” and “Middle East”, to identify observational studies on AMR published from January 2011 to June 2018. Data were extracted from included articles on a predefined set of variables. Percentages of AMR were analysed as median and interquartile ranges. Risk of bias was assessed using the Newcastle-Ottawa Scale. Results: A total of 132 articles met the inclusion criteria. Included studies showed heterogeneity in study design, laboratory methods and standards for interpretation of results, and an overall high risk of bias. Main findings were the following:1. High proportions of carbapenem resistance in Acinetobacter spp. (median 74.2%: range), and both carbapenem resistance (median 8.1% and 15.4% for E. coli and K. pneumoniae respectively) and ESBL-production (median 32.3% and 27.9% for E. coli and K. pneumoniae respectively) amongst Enterobacteriaceae. S. aureus isolates showed a median methicillin resistance percentage of 45.1%, while vancomycin resistance was almost absent. A median of 50% of the strains of S. pneumoniae showed non-susceptibility to penicillin. 2. Similar trends were observed in conflict and non-conflict affected countries.Conclusions: There is a lack of standardization in the methodological approach to AMR research in the Middle East. The proportion of antibiotic resistances among specific GLASS pathogens is high, particularly among Acinetobacter spp.

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“…Mutations of GtfA, including N98A, E244A, E332A and S403A, block the glycosylation of PsrP (2,10). To date, 94 S. pneumoniae serotypes have been found (11)(12)(13)(14). Previous studies showed that PsrP was only detected in 51.7% of invasive S. pneumoniae isolates and in 48.3% of carrier S. pneumoniae isolates (15), thus, we sought to examine if the presence of the PsrP-SecY2A2 island is associated to a certain serotype of S. pneumoniae, or if GtfA and GtfB are conserved among these S. pneumoniae isolates and involved in the glycosylation of PsrP via the formation of the glycosyltransferase complex GtfA-GtfB.…”

Section: Introductionmentioning

confidence: 99%

GtfA Interacting with GtfB is Required for PsrP Glycosylation in Streptococcus pneumoniae

Jin

Zeng³

et al. 2018

Jundishapur J Microbiol

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Background: Streptococcus pneumoniae can adhere to lung cells via many adhesins, including pneumococcal serine-rich repeat protein (PsrP). Glycosyltransferase A (GtfA) and glycoslytransferase B (GtfB) were found to initiate PsrP glycosylation in Streptococcus pneumoniae serotype 4, isolate TIGR4. Objectives: To test whether GtfA and GtfB are conserved among S. pneumoniae isolates presenting with different serotypes and are involved in the glycosylation of PsrP via formation of the glycosyltransferase complex GtfA-GtfB. Methods: Serotyping of S. pneumoniae was performed using polymerase chain reaction (PCR) assays. The evolutionary divergences of GtfA and GtfB among different isolates were estimated using MEGA4 software. The contribution of GtfA and GtfB to the glycosylation of PsrP was identified using an in vivo glycosylation system in Escherichia coli. Interaction of GtfA with GtfB was assessed using a glutathione S-transferase (GST) pull-down assay and yeast two-hybrid experiment. Results: Nine different S. pneumoniae serotypes were found, of which the most frequent was 19F. The pneumococcal isolate TIGR4 and 22 other clinical isolates were included to estimate evolutionary divergence. The average homologies of the GtfA and GtfB sequences were 99.59% and 98.53%, respectively. Glycosyltransferase A and GtfB were shown to be required for the transfer of Nacetylglucosamine moieties to PsrP1-374. Glutathione S-transferase pull-down assays and yeast two-hybrid experiments showed that GtfA directly interacted with GtfB. Conclusions: Glycosyltransferase A and GtfB are conserved in S. pneumoniae isolates. Glycosyltransferase A interacts with GtfB, forming the glycosyltransferase complex GtfA-GtfB, which is required for PsrP glycosylation.

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Emergence of Neoteric Serotypes Among Multidrug Resistant Strains of Streptococcus pneumoniae Prevalent in Egypt

Cited by 9 publications

References 32 publications

Development and evaluation of a novel vaccine against prevalent invasive multi-drug resistant strains ofStreptococcus pneumoniae

Development and evaluation of a novel vaccine against prevalent invasive multi-drug resistant strains ofStreptococcus pneumoniae

Antimicrobial resistance among GLASS pathogens in conflict and non-conflict affected settings in the Middle East: A systematic review

GtfA Interacting with GtfB is Required for PsrP Glycosylation in Streptococcus pneumoniae

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