scholarly journals Comparative analysis of prophage-like elements inHelicobactersp. genomes

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2012 ◽  
Author(s):  
Xiangyu Fan ◽  
Yumei Li ◽  
Rong He ◽  
Qiang Li ◽  
Wenxing He

Prophages are regarded as one of the factors underlying bacterial virulence, genomic diversification, and fitness, and are ubiquitous in bacterial genomes. Information onHelicobactersp. prophages remains scarce. In this study, sixteen prophages were identified and analyzed in detail. Eight of them are described for the first time. Based on a comparative genomic analysis, these sixteen prophages can be classified into four different clusters. Phylogenetic relationships of Cluster AHelicobacterprophages were investigated. Furthermore, genomes ofHelicobacterprophages from Clusters B, C, and D were analyzed. Interestingly, some putative antibiotic resistance proteins and virulence factors were associated withHelicobacterprophages.

Gut Pathogens ◽  
2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Seung Woo Ahn ◽  
Se Hee Lee ◽  
Hong-Seok Son ◽  
Seong Woon Roh ◽  
Yoon-E Choi

Abstract Background Lentibacillus species are gram variable aerobic bacteria that live primarily in halophilic environments. Previous reports have shown that bacteria belonging to this species are primarily isolated from salty environments or food. We isolated a bacterial strain CBA3610, identified as a novel species of the genus Lentibacillus, from a human fecal sample. In this report, the whole genome sequence of Lentibacillus sp. CBA3610 is presented, and genomic analyses are performed. Results Complete genome sequence of strain CBA3610 was obtained through PacBio RSII and Illumina HiSeq platforms. The size of genome is 4,035,571 bp and genes estimated to be 4714 coding DNA sequences and 64 tRNA and 17 rRNA were identified. The phylogenetic analysis confirmed that it belongs to the genus Lentibacillus. In addition, there were genes related to antibiotic resistance and virulence, and genes predicted as CRISPR and prophage were also identified. Genes related to osmotic stress were found according to the characteristics of halophilic bacterium. Genomic differences from other Lentibacillus species were also confirmed through comparative genomic analysis. Conclusions Strain CBA3610 is predicted to be a novel candidate species of Lentibacillus through phylogenetic analysis and comparative genomic analysis with other species in the same genus. This strain has antibiotic resistance gene and pathogenic genes. In future, the information derived from the results of several genomic analyses of this strain is thought to be helpful in identifying the relationship between halophilic bacteria and human gut microbiota.


Pathogens ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 330 ◽  
Author(s):  
Zhenghui Liu ◽  
Hongyan Sheng ◽  
Benjamin Azu Okorley ◽  
Yu Li ◽  
Frederick Leo Sossah

Ewingella americana is a cosmopolitan bacterial pathogen that has been isolated from many hosts. Here, we sequenced a high-quality genome of E. americana B6-1 isolated from Flammulina filiformis, an important cultivated mushroom, performed a comparative genomic analysis with four other E. americana strains from various origins, and tested the susceptibility of B6-1 to antibiotics. The genome size, predicted genes, and GC (guanine-cytosine) content of B6-1 was 4.67 Mb, 4301, and 53.80%, respectively. The origin of the strains did not significantly affect the phylogeny, but mobile genetic elements shaped the evolution of the genus Ewingella. The strains encoded a set of common genes for type secretion, virulence effectors, CAZymes, and toxins required for pathogenicity in all hosts. They also had antibiotic resistance, pigments to suppress or evade host defense responses, as well as genes for adaptation to different environmental conditions, including temperature, oxidation, and nutrients. These findings provide a better understanding of the virulence, antibiotic resistance, and host adaptation strategies of Ewingella, and they also contribute to the development of effective control strategies.


2019 ◽  
pp. 99-112 ◽  
Author(s):  
Khashayar SHAHIN ◽  
Majid BOUZARI ◽  
Ran WANG

Shigellosis is one of the most important acute enteric infections caused by different species of Shigella, such as Shigella flexneri. Despite the use of antibiotic therapy to reduce disease duration, this approach is becoming less effective due to the emergence of antibiotic resistance among Shigella spp. Bacteriophages have been introduced as an alternative for controlling shigellosis. However, the bacteriophages must be without any lysogenic or virulence factors, toxin coding, or antibiotic-resistant genes. In this study, the whole genome sequence of vB_SflS-ISF001, a virulent Siphoviridae bacteriophage specific for Shigella flexneri, was obtained, and a comparative genomic analysis was carried out to identify its properties and safety. vB_SflS-ISF001 genomic DNA was measured at 50,552 bp with 78 deduced open reading frames (ORFs), with 24 ORFs (30.77%) sharing similarities with proteins from the genomes of homologous phages that had been reported earlier. Genetic analysis classifies it under the genus T1virus of the subfamily Tunavirinae. Moreover, comparative genomic analysis revealed no undesirable genes in the genome of vB_SflS-ISF001, such as antibiotic resistance, virulence, lysogeny, or toxin-coding genes. The results of this investigation indicate that vB_SflS-ISF001 is a new species, and confirm its safety for the biocontrol of S. flexneri.


2020 ◽  
Author(s):  
Pieter De Maayer ◽  
Talia Pillay ◽  
Teresa A Coutinho

Abstract Background Flagellar motility is an efficient means of movement that allows bacteria to successfully colonize and compete with other microorganisms within their respective environments. The production and functioning of these structures is highly energy intensive and as such flagellar motility is a tightly regulated process. Despite this, some bacteria have been observed to possess multiple flagellar systems which allow distinct forms of motility. Results Comparative genomic analyses showed that, in addition to the previously identified primary peritrichous (flag-1) and secondary, lateral (flag-2) flagellar loci, three novel types of flagellar loci, varying in both gene content and gene order, are encoded on the genomes of members of the order Enterobacterales. The flag-3 and flag-4 loci encode peritrichous flagellar systems while the flag-5 locus encodes a polar flagellum. In total, 798/4,028 (~ 20%) of the studied taxa incorporate dual flagellar systems, while nineteen taxa incorporate three distinct flagellar loci. Phylogenetic analyses indicate the complex evolutionary histories of the flagellar systems among the Enterobacterales. Conclusions Supernumerary flagellar loci are relatively common features across a broad taxonomic spectrum in the order Enterobacterales. Here, we report for the first time on the occurrence of two peritrichous flagellar loci in some enterobacterial taxa, as well as the occurrence of three flagellar systems in select members of the Enterobacterales. Considering the energetic burden of maintaining and operating multiple flagellar systems, they are likely to play a role in the ecological success of members of this family and we postulate on their potential biological functions.


2011 ◽  
Vol 55 (4) ◽  
pp. 1520-1526 ◽  
Author(s):  
Maria Soledad Ramirez ◽  
Mark D. Adams ◽  
Robert A. Bonomo ◽  
Daniela Centrón ◽  
Marcelo E. Tolmasky

ABSTRACTAcinetobacter baumanniiA118, a naturally competent clinical isolate, is unusually susceptible to several antibiotics. Comparison of the optical map of strain A118 within silico-generated restriction maps of sequenced genomes and sequence analyses showed that the AbaR region, commonly found inserted within thecomMgene in other isolates, is missing in strain A118, which could in part explain the susceptible phenotype exhibited by this isolate. These comparative studies also showed differences in regions where genes coding for functions that may be involved in drug resistance or susceptibility are located. Further sequencing demonstrated thatcatandblaADC, namedblaADC-55, are present but that atet(A) gene usually found in other strains is not. In addition,carOandpbp2, which may play a role in susceptibility to carbapenems, are present in strain A118. These findings support the idea thatA. baumanniistrains possess multiple mechanisms that contribute to antibiotic resistance, and the presence of some of them is not sufficient for a resistant phenotype. The results shown here indicate that optical mapping is a useful tool for preliminary comparative genomic analysis.


2009 ◽  
Vol 191 (15) ◽  
pp. 4854-4862 ◽  
Author(s):  
Patricia Romero ◽  
Nicholas J. Croucher ◽  
N. Luisa Hiller ◽  
Fen Z. Hu ◽  
Garth D. Ehrlich ◽  
...  

ABSTRACT Streptococcus pneumoniae is an important human pathogen that often carries temperate bacteriophages. As part of a program to characterize the genetic makeup of prophages associated with clinical strains and to assess the potential roles that they play in the biology and pathogenesis in their host, we performed comparative genomic analysis of 10 temperate pneumococcal phages. All of the genomes are organized into five major gene clusters: lysogeny, replication, packaging, morphogenesis, and lysis clusters. All of the phage particles observed showed a Siphoviridae morphology. The only genes that are well conserved in all the genomes studied are those involved in the integration and the lysis of the host in addition to two genes, of unknown function, within the replication module. We observed that a high percentage of the open reading frames contained no similarities to any sequences catalogued in public databases; however, genes that were homologous to known phage virulence genes, including the pblB gene of Streptococcus mitis and the vapE gene of Dichelobacter nodosus, were also identified. Interestingly, bioinformatic tools showed the presence of a toxin-antitoxin system in the phage φSpn_6, and this represents the first time that an addition system in a pneumophage has been identified. Collectively, the temperate pneumophages contain a diverse set of genes with various levels of similarity among them.


Genes ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1504
Author(s):  
Wenwei Lu ◽  
Zhangming Pei ◽  
Mengning Zang ◽  
Yuan-kun Lee ◽  
Jianxin Zhao ◽  
...  

The potential probiotic benefits of Bifidobacterium bifidum have received increasing attention recently. We used comparative genomic analysis to explore the differences in the genome and the physiological characteristics of B. bifidum isolated from the fecal samples of Chinese adults and infants. The relationships between genotypes and phenotypes were analyzed to assess the effects of isolation sources on the genetic variation of B. bifidum. The phylogenetic tree results indicated that the phylogeny of B. bifidum may be related to the geographical features of its isolation source. B. bifidum was found to have an open pan-genome and a conserved core genome. The genetic diversity of B. bifidum is mainly reflected in carbohydrate metabolism- and immune/competition-related factors, such as the glycoside hydrolase gene family, bacteriocin operons, antibiotic resistance genes, and clustered regularly interspaced short palindromic repeats (CRISPR)-Cas. Additionally, the type III A CRISPR-Cas system was discovered in B. bifidum for the first time. B. bifidum strains exhibited niche-specific characteristics, and the results of this study provide an improved understanding of the genetics of this species.


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