Genome diversity and evolutionary characteristics of clinical isolates of Bordetella pertussis circulating in Iran

2020 ◽  
Author(s):  
Samaneh Saedi ◽  
Azadeh Safarchi ◽  
Mojtaba Noofeli ◽  
Keyvan Tadayon ◽  
Alfred Chin Yen Tay ◽  
...  
Keyword(s):  
Bordetella Pertussis ◽  
Genome Structure ◽  
Genomic Analysis ◽  
Clinical Isolates ◽  
Comparative Genomic ◽  
Waning Immunity ◽  
Promoter Allele ◽  
Structural Adaptations ◽  
Reference Strains ◽  
Unique Snps

  Background and Objectives: The re-emergence of pertussis still is being reported all over the world. Pathogen adaptation and antigenic divergence of circulating isolates from vaccine strains are the main reasons of infection resurgence. Waning immunity is also an important factor contributing to resurgence of pertussis. Materials and Methods: The genetic diversity and evolutionary characteristics of circulating Iranian isolates of Bordetella pertussis during February 2015 to October 2018 was investigated by pulsed-field gel electrophoresis (PFGE) and subse- quently ptxA, ptxP and fim3 alleles were characterized. The next generation genome sequencing was then used to compare the genomics of ptxP1 and ptxP3 of selected isolates from PFGE dendrogram. Results: PFGE differentiated 62 clinical isolates and vaccine and reference strains into 19 PFGE profiles, indicating the higher level of heterogeneity in the population during 2015-2018. The predominant B. pertussis genotype harbored pertussis toxin promoter allele, ptxP3 and the expansion of ptxA1 isolates, were also observed in our population. Conclusion: No changes in allelic profile of predominant clone in recent years was observed but antigenic divergence between recently circulating isolates and the vaccine strain has been progressed and significantly was higher than previous studies. The comparative genomic analysis of the ptxP3 and ptxP1 isolates indicate that changes in ptxP3 genome structure including 32 unique SNPs and three unique indels may have contributed to the expansion of the ptxP3 clone. We compared ptxP3 and ptxP1 isolates in pathogenicity-associated genes and found five of them were specific for the ptxP3 isolates. The polymorphisms in pathogenicity-associated genes suggest structural adaptations for these virulence factors.  

scholarly journals Taxonomic scheme of the order Chaetophorales (Chlorophyceae, Chlorophyta) based on Chloroplast genomes

2020 ◽  
Author(s):  
Benwen Liu ◽  
Yu Xin Hu ◽  
Zheng Yu Hu ◽  
Guo Xiang Liu ◽  
Huan Zhu
Keyword(s):  
Phylogenetic Analysis ◽  
Chloroplast Genome ◽  
Phylogenetic Relationships ◽  
Phylogenetic Analyses ◽  
Genome Structure ◽  
Genomic Analysis ◽  
Comparative Genomic ◽  
Rdna Sequences ◽  
Chloroplast Genomes ◽  
Basal Clade

Abstract Background Order Chaetophorales currently includes six families, namely Schizomeridaceae, Aphanochaetaceae, Barrancaceae, Uronemataceae, Fritschiellaceae, and Chaetophoraceae. Most studies have primarily focused on intergeneric phylogenetic relationships within this order and the phylogenetic relationships with four other Chlorophycean orders (Chaetophorales, Chaetopeltidales and Oedogoniales, and Volvocales). This study aimed to phylogenetically reconstruct order Chaetophorales and determine the taxonomic scheme and to further the current understanding of the evolution of order Chaetophorales. The taxonomic scheme of Chaetophorales has been inferred primarily through phylogenetic analysis based on rDNA sequences and phylogenetic relationships among families in order Chaetophorales remain unclear. Results In present study, seven complete and five fragmentary chloroplast genomes were harvested. Phylogenomic and comparative genomic analysis were performed to determine the taxonomic scheme within Chaetophorales. Consequently, Oedogoniales was found to be a sister to a clade linking Chaetophorales and Chaetopeltidales, Schizomeriaceae, and Aphanochaetaceae clustered into a well-resolved basal clade in Chaetophorales, inconsistent with the results of phylogenetic analysis based on rDNA sequences. Comparative genomic analyses revealed that the chloroplast genomes of Schizomeriaceae and Aphanochaetaceae were highly conserved and homologous, highlighting the closest relationship in this order. Germination types of zoospores precisely correlated with the phylogenetic relationships. Conclusions In conclusion, chloroplast genome structure analyses, synteny analyses, and zoospore germination analyses were concurrent with phylogenetic analyses based on the chloroplast genome, and all of them robustly determined the unique taxonomic scheme of Chaetophorales and the relationships of Oedogoniales, Chaetophorales, and Chaetopeltidales.

scholarly journals Taxonomic scheme of the order Chaetophorales (Chlorophyceae, Chlorophyta) based on Chloroplast genomes

2020 ◽  
Author(s):  
Benwen Liu(Former Corresponding Author) ◽  
Yu Xin Hu ◽  
Zheng Yu Hu ◽  
Guo Xiang Liu ◽  
Huan Zhu(New Corresponding Author)
Keyword(s):  
Phylogenetic Analysis ◽  
Chloroplast Genome ◽  
Phylogenetic Relationships ◽  
Phylogenetic Analyses ◽  
Genome Structure ◽  
Genomic Analysis ◽  
Comparative Genomic ◽  
Rdna Sequences ◽  
Chloroplast Genomes ◽  
Basal Clade

Abstract Background: Order Chaetophorales currently includes six families, namely Schizomeridaceae, Aphanochaetaceae, Barrancaceae, Uronemataceae, Fritschiellaceae, and Chaetophoraceae. The phylogenetic relationships of Chaetophorales have been inferred primarily through phylogenetic analysis based on rDNA sequences. Most studies have primarily focused on intergeneric phylogenetic relationships within this order and the phylogenetic relationships with four other Chlorophycean orders (Chaetophorales, Chaetopeltidales and Oedogoniales, and Volvocales). The phylogenetic relationships among families in order Chaetophorales remain unclear. This study aimed to phylogenetically reconstruct order Chaetophorales and determine the taxonomic scheme and to further the current understanding of the evolution of order Chaetophorales . Results: In the present study, seven complete and five fragmentary chloroplast genomes were harvested. Phylogenomic and comparative genomic analysis were performed to determine the taxonomic scheme within Chaetophorales. Consequently, Oedogoniales was found to be a sister to a clade linking Chaetophorales and Chaetopeltidales. Schizomeriaceae, and Aphanochaetaceae clustered into a well-resolved basal clade in Chaetophorales, inconsistent with the results of phylogenetic analysis based on rDNA sequences. Comparative genomic analyses revealed that the chloroplast genomes of Schizomeriaceae and Aphanochaetaceae were highly conserved and homologous, highlighting the closest relationship in this order. Germination types of zoospores precisely correlated with the phylogenetic relationships. Conclusions: chloroplast genome structure analyses, synteny analyses, and zoospore germination analyses were concurrent with phylogenetic analyses based on the chloroplast genome, and all of them robustly determined the unique taxonomic scheme of Chaetophorales and the relationships of Oedogoniales, Chaetophorales, and Chaetopeltidales.

scholarly journals Insight into Evolution of Bordetella pertussis from Comparative Genomic Analysis: Evidence of Vaccine-Driven Selection

2010 ◽  
Vol 28 (1) ◽  
pp. 707-715 ◽  
Author(s):  
Sophie Octavia ◽  
Ram P. Maharjan ◽  
Vitali Sintchenko ◽  
Gordon Stevenson ◽  
Peter R. Reeves ◽  
...  
Keyword(s):  
Bordetella Pertussis ◽  
Genomic Analysis ◽  
Comparative Genomic Analysis ◽  
Comparative Genomic ◽  
Insight Into
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