177 research outputs found
Pan and Core Genome Analysis of 183 Mycobacterium tuberculosis Strains Revealed a High Inter-Species Diversity among the Human Adapted Strains
Tuberculosis (TB) is an airborne communicable disease with high morbidity and mortality rates, especially in developing countries. The causal agents of TB belong to the complex Mycobacterium tuberculosis (MTBc), which is composed of different human and animal TB associated species. Some animal associated species have zoonotic potential and add to the burden of TB management. The BCG (“Bacillus Calmette-Guérin”) vaccine is widely used for the prevention against TB, but its use is limited in immunocompromised patients and animals due to the adverse effects and disseminated life-threatening complications. In this study, we aimed to carry out a comparative genome analysis between the human adapted species including BCG vaccine strains to identify and pinpoint the conserved genes related to the virulence across all the species, which could add a new value for vaccine development. For this purpose, the sequences of 183 Mycobacterium tuberculosis (MTB) strains were retrieved from the freely available WGS dataset at NCBI. The species included: 168 sensu stricto MTB species with other human MTB complex associated strains: M. tuberculosis var. africanum (3), M. tuberculosis var. bovis (2 draft genomes) and 10 BCG species, which enabled the analysis of core genome which contains the conserved genes and some virulence factor determinants. Further, a phylogenetic tree was constructed including the genomes of human (183); animals MTB adapted strains (6) and the environmental Mycobacterium strain “M. canettii”. Our results showed that the core genome consists of 1166 conserved genes among these species, which represents a small portion of the pangenome (7036 genes). The remaining genes in the pangenome (5870) are accessory genes, adding a high inter-species diversity. Further, the core genome includes several virulence-associated genes and this could explain the rare infectiousness potential of some attenuated vaccine strains in some patients. This study reveals that low number of conserved genes in human adapted MTBc species and high inter-species diversity of the pan-genome could be considered for vaccine candidate development
Pan and Core Genome Analysis of 183 Mycobacterium tuberculosis Strains Revealed a High Inter-Species Diversity among the Human Adapted Strains
Tuberculosis (TB) is an airborne communicable disease with high morbidity and mortality rates, especially in developing countries. The causal agents of TB belong to the complex Mycobacterium tuberculosis (MTBc), which is composed of different human and animal TB associated species. Some animal associated species have zoonotic potential and add to the burden of TB management. The BCG (“Bacillus Calmette-Guérin”) vaccine is widely used for the prevention against TB, but its use is limited in immunocompromised patients and animals due to the adverse effects and disseminated life-threatening complications. In this study, we aimed to carry out a comparative genome analysis between the human adapted species including BCG vaccine strains to identify and pinpoint the conserved genes related to the virulence across all the species, which could add a new value for vaccine development. For this purpose, the sequences of 183 Mycobacterium tuberculosis (MTB) strains were retrieved from the freely available WGS dataset at NCBI. The species included: 168 sensu stricto MTB species with other human MTB complex associated strains: M. tuberculosis var. africanum (3), M. tuberculosis var. bovis (2 draft genomes) and 10 BCG species, which enabled the analysis of core genome which contains the conserved genes and some virulence factor determinants. Further, a phylogenetic tree was constructed including the genomes of human (183); animals MTB adapted strains (6) and the environmental Mycobacterium strain “M. canettii”. Our results showed that the core genome consists of 1166 conserved genes among these species, which represents a small portion of the pangenome (7036 genes). The remaining genes in the pangenome (5870) are accessory genes, adding a high inter-species diversity. Further, the core genome includes several virulence-associated genes and this could explain the rare infectiousness potential of some attenuated vaccine strains in some patients. This study reveals that low number of conserved genes in human adapted MTBc species and high inter-species diversity of the pan-genome could be considered for vaccine candidate development
Cleavage site and Ectodomain of HA2 sub-unit sequence of three equine influenza virus isolated in Morocco
Abstract
Background
The equine influenza (EI) is an infectious and contagious disease of the upper respiratory tract of horses. Two outbreaks were notified in Morocco during 1997 and 2004 respectively in Nador and Essaouira. The aims of the present study concern the amino acids sequences comparison with reference strain A/equine/Miami/1963(H3N8) of the HA2 subunit including the cleavage site of three equine influenza viruses (H3N8) isolated in Morocco: A/equine/Nador/1/1997(H3N8), A/equine/Essaouira/2/2004 (H3N8) and A/equine/Essaouira/3/2004 (H3N8).
Results
The obtained results demonstrated that the substitutions were located at Ectodomain (ED) and transmembrane domain (TD), and they have only one arginine in cleavage site (HA1-PEKQI-R329-GI-HA2). In the Ectodomain, the mutation N/154
2
/T deleted the NGT glycosylation site at position 154 for both strains A/equine/Essaouira/2/2004(H3N8) and A/equine/Essaouira/3/2004(H3N8). Except for mutation D/1602/Y of the A/equine/Nador/1/1997(H3N8) strain, the other mutations were involved in non conserved sites. While the transmembrane domain (TM) of the strain A/equine/Essaouira/3/2004(H3N8) exhibits a substitution at residue C/199
2
/F. For the A/equine/Nador/1/1997(H3N8) strain the HA2 shows a mutation at residue M/207
2
/L. Three Moroccan strains reveals a common substitution at the residue E/211
2
/Q located between transmembrane domain TM and the cytoplasmic domain (CD).
Conclusion
The given nature virulence of three Moroccan strains, the identified and reported mutations certainly played a permissive role of infection viral process.
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Computational genomics-proteomics and Phylogeny analysis of twenty one mycobacterial genomes (Tuberculosis & non Tuberculosis strains)
The genus Mycobacterium comprises different species, among them the most contagious and infectious bacteria. The members of the complex Mycobacterium tuberculosis are the most virulent microorganisms that have killed human and other mammals since millennia. Additionally, with the many different mycobacterial sequences available, there is a crucial need for the visualization and the simplification of their data. In this present study, we aim to highlight a comparative genome, proteome and phylogeny analysis between twenty-one mycobacterial (Tuberculosis and non tuberculosis) strains using a set of computational and bioinformatics tools (Pan and Core genome plotting, BLAST matrix and phylogeny analysis).Results
Considerably the result of pan and core genome Plotting demonstrated that less than 1250 Mycobacterium gene families are conserved across all species, and a total set of about 20,000 gene families within the Mycobacterium pan-genome of twenty one mycobacterial genomes.Viewing the BLAST matrix a high similarity was found among the species of the complex Mycobacterium tuberculosis and less conservation is found with other slow growing pathogenic mycobacteria.
Phylogeny analysis based on both protein conservation, as well as rRNA clearly resolve known relationships between slow growing mycobacteria.Conclusion
Mycobacteria include important pathogenic species for human and animals and the Mycobacterium tuberculosis complex is the most cause of death of the humankind. The comparative genome analysis could provide a new insight for better controlling and preventing these diseases
Computational genomics-proteomics and Phylogeny analysis of twenty one mycobacterial genomes (Tuberculosis & non Tuberculosis strains)
The genus Mycobacterium comprises different species, among them the most contagious and infectious bacteria. The members of the complex Mycobacterium tuberculosis are the most virulent microorganisms that have killed human and other mammals since millennia. Additionally, with the many different mycobacterial sequences available, there is a crucial need for the visualization and the simplification of their data. In this present study, we aim to highlight a comparative genome, proteome and phylogeny analysis between twenty-one mycobacterial (Tuberculosis and non tuberculosis) strains using a set of computational and bioinformatics tools (Pan and Core genome plotting, BLAST matrix and phylogeny analysis).Results
Considerably the result of pan and core genome Plotting demonstrated that less than 1250 Mycobacterium gene families are conserved across all species, and a total set of about 20,000 gene families within the Mycobacterium pan-genome of twenty one mycobacterial genomes.Viewing the BLAST matrix a high similarity was found among the species of the complex Mycobacterium tuberculosis and less conservation is found with other slow growing pathogenic mycobacteria.
Phylogeny analysis based on both protein conservation, as well as rRNA clearly resolve known relationships between slow growing mycobacteria.Conclusion
Mycobacteria include important pathogenic species for human and animals and the Mycobacterium tuberculosis complex is the most cause of death of the humankind. The comparative genome analysis could provide a new insight for better controlling and preventing these diseases
Cell-wall synthesis and ribosome maturation are co-regulated by an RNA switch in Mycobacterium tuberculosis
The success of Mycobacterium tuberculosis relies on the ability to switch between active growth and non-replicating persistence, associated with latent TB infection. Resuscitation promoting factors (Rpfs) are essential for the transition between these states. Rpf expression is tightly regulated as these enzymes are able to degrade the cell wall, and hence potentially lethal to the bacterium itself. We have identified a regulatory element in the 5' untranslated region (UTR) of rpfB. We demonstrate that this element is a transcriptionally regulated RNA switch/riboswitch candidate, which appears to be restricted to pathogenic mycobacteria, suggesting a role in virulence. We have used translation start site mapping to re-annotate the RpfB start codon and identified and validated a ribosome binding site that is likely to be targeted by an rpfB antisense RNA. Finally, we show that rpfB is co-transcribed with ksgA and ispE downstream. ksgA encodes a universally conserved methyltransferase involved in ribosome maturation and ispE encodes an essential kinase involved in cell wall synthesis. This arrangement implies co-regulation of resuscitation, cell wall synthesis and ribosome maturation via the RNA switch
Epidemiology of extended-spectrum β-lactamase producing Escherichia coli from hospital settings in Yemen
Introduction: Infection with Extended spectrum β-lactamases (ESBLs) producing bacteria is considered as serious health problem worldwide. The aim of this cross-sectional study was to investigate the prevalence of ESBL producing Escherichia coli in hospitalized patients and the risk factors contributed for its nosocomial infections in addition to the antibiotics susceptibility patterns of isolates from 130 inpatients collected in Al Thawra General Hospital and Al-Kuwait University Hospital in Sana’a city.
Methodology: Antibiotic susceptibility testing and confirmation of ESBL production were performed according to the Clinical and Laboratory Standards Institute guidelines.
Results: Out of 130 E. coli isolates, 44 (33.8%) were ESBLs producers, the majority of ESBLs producers were in wound exudates samples (52.2%). The highest significant rates were among the elderly, patients with previous hospitalization, patients who have stayed in hospital more than 22 days, patients who have taken third generation cephalosporins as treatment and diabetic patients. All ESBL-producing isolates were resistant to amoxicillin, trimethoprim-sulfamethoxazole and the third generation cephalosporins (100%). Resistance to other antimicrobial agents among these isolates was: amoxicillin-clavulanic acid (90.9%), nalidixic acid (95.5%), ciprofloxacin (90.9%), ofloxacin (88.6%) and tetracycline (54.5%). The most effective antibiotics in vitro for both types of isolates (ESBL producing and non ESBL producing E. coli) were Imipenem (100%), Amikacin (75%) and (93.0%), respectively, and Pipracillin-tazobactam (68.2%) and (88.4%), respectively.
Conclusion: ESBLs detection tests must be performed as routine work in all hospitals and laboratories. Furthermore, a strict adherence of infection control policies and procedures with continuous antibiotics resistance surveillance are important to prevent nosocomial infections
Viral RNA Metagenomics of Hyalomma Ticks Collected from Dromedary Camels in Makkah Province, Saudi Arabia
Arthropod-borne infections are a medical and economic threat to humans and livestock. Over the last three decades, several unprecedented viral outbreaks have been recorded in the Western part of the Arabian Peninsula. However, little is known about the circulation and diversity of arthropod-borne viruses in this region. To prepare for new outbreaks of vector-borne diseases, it is important to detect which viruses circulate in each vector population. In this study, we used a metagenomics approach to characterize the RNA virome of ticks infesting dromedary camels (Camelus dromedaries) in Makkah province, Saudi Arabia. Two hundred ticks of species Hyalomma dromedarii (n = 196) and Hyalomma impeltatum (n = 4) were collected from the Alkhurma district in Jeddah and Al-Taif city. Virome analysis showed the presence of several tick-specific viruses and tick-borne viruses associated with severe illness in humans. Some were identified for the first time in the Arabian Peninsula. The human disease-associated viruses detected included Crimean Congo Hemorrhagic fever virus and Tamdy virus (family Nairoviridae), Guertu virus (family Phenuiviridae), and a novel coltivirus that shares similarities with Tarumizu virus, Tai forest reovirus and Kundal virus (family Reoviridae). Furthermore, Alkhurma hemorrhagic virus (Flaviviridae) was detected in two tick pools by specific qPCR. In addition, tick-specific viruses in families Phenuiviridae (phleboviruses), Iflaviridae, Chuviridae, Totiviridae and Flaviviridae (Pestivirus) were detected. The presence of human pathogenetic viruses warrants further efforts in tick surveillance, xenosurveillence, vector control, and sero-epidemiological investigations in human and animal populations to predict, contain and mitigate future outbreaks in the region
Viral RNA Metagenomics of Hyalomma Ticks Collected from Dromedary Camels in Makkah Province, Saudi Arabia
Arthropod-borne infections are a medical and economic threat to humans and livestock. Over the last three decades, several unprecedented viral outbreaks have been recorded in the Western part of the Arabian Peninsula. However, little is known about the circulation and diversity of arthropod-borne viruses in this region. To prepare for new outbreaks of vector-borne diseases, it is important to detect which viruses circulate in each vector population. In this study, we used a metagenomics approach to characterize the RNA virome of ticks infesting dromedary camels (Camelus dromedaries) in Makkah province, Saudi Arabia. Two hundred ticks of species Hyalomma dromedarii (n = 196) and Hyalomma impeltatum (n = 4) were collected from the Alkhurma district in Jeddah and Al-Taif city. Virome analysis showed the presence of several tick-specific viruses and tick-borne viruses associated with severe illness in humans. Some were identified for the first time in the Arabian Peninsula. The human disease-associated viruses detected included Crimean Congo Hemorrhagic fever virus and Tamdy virus (family Nairoviridae), Guertu virus (family Phenuiviridae), and a novel coltivirus that shares similarities with Tarumizu virus, Tai forest reovirus and Kundal virus (family Reoviridae). Furthermore, Alkhurma hemorrhagic virus (Flaviviridae) was detected in two tick pools by specific qPCR. In addition, tick-specific viruses in families Phenuiviridae (phleboviruses), Iflaviridae, Chuviridae, Totiviridae and Flaviviridae (Pestivirus) were detected. The presence of human pathogenetic viruses warrants further efforts in tick surveillance, xenosurveillence, vector control, and sero-epidemiological investigations in human and animal populations to predict, contain and mitigate future outbreaks in the region
Molecular diagnosis and enrichment culture identified a septic pseudoarthrosis due to an infection with Erysipelatoclostridium ramosum.
We describe here a rare case of septic pseudarthrosis due to Erysipelatoclostridium ramosum in a female young patient. The patient, currently in remission from Ewing's sarcoma treated by a bone resection and allograft combined with chemotherapy, suffered from a chronic femoral pseudarthrosis in a context of bone insufficiency and graft resorption. A broad range 16S PCR followed by sequencing, as well as an enrichment culture of a bone biopsy revealed the presence of E. ramosum, an anaerobic firmicute with a low Gram-positive affinity staining and low GC content, that was further characterized by whole genome sequencing (WGS)
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