scholarly journals Similarity in the Structure of tetD-Carrying Mobile Genetic Elements in Bacterial Strains of Different Genera Isolated from Cultured Yellowtail

2016 ◽  
Vol 21 (3) ◽  
pp. 183-186 ◽  
Author(s):  
MANABU FURUSHITA ◽  
HIROSHI AKAGI ◽  
AZUSA KANEOKA ◽  
TOSHIMICHI MAEDA ◽  
TSUBASA FUKUDA ◽  
...  
2021 ◽  
Author(s):  
Fatima Aysha Hussain ◽  
Javier Dubert ◽  
Joseph Elsherbini ◽  
Mikayla Murphy ◽  
David VanInsberghe ◽  
...  

AbstractAlthough it is generally accepted that viruses (phages) drive bacterial evolution, how these dynamics play out in the wild remains poorly understood. Here we show that the arms race between phages and their hosts is mediated by large and highly diverse mobile genetic elements. These phage-defense elements display exceedingly fast evolutionary turnover, resulting in differential phage susceptibility among clonal bacterial strains while phage receptors remain invariant. Protection afforded by multiple elements is cumulative, and a single bacterial genome can harbor as many as 18 putative phage-defense elements. Overall, elements account for 90% of the flexible genome amongst closely related strains. The rapid turnover of these elements demonstrates that phage resistance is unlinked from other genomic features and that resistance to phage therapy might be as easily acquired as antibiotic resistance.


2017 ◽  
Author(s):  
Frederic Bertels ◽  
Chaitanya S. Gokhale ◽  
Arne Traulsen

ABSTRACTMobile genetic elements can be found in almost all genomes. Possibly the most common non-autonomous mobile genetic elements in bacteria are REPINs that can occur hundreds of times within a genome. The sum of all REPINs within a genome are an evolving populations because they replicate and mutate. We know the exact composition of this population and the sequence of each member of a REPIN population, in contrast to most other biological populations. Here, we model the evolution of REPINs as quasispecies. We fit our quasispecies model to ten different REPIN populations from ten different bacterial strains and estimate duplication rates. We find that our estimated duplication rates range from about 5 × 10−9to 37 × 10−9duplications per generation per genome. The small range and the low level of the REPIN duplication rates suggest a universal trade-off between the survival of the REPIN population and the reduction of the mutational load for the host genome. The REPIN populations we investigated also possess features typical of other natural populations. One population shows hallmarks of a population that is going extinct, another population seems to be growing in size and we also see an example of competition between two REPIN populations.


2020 ◽  
Vol 76 (1) ◽  
pp. 48-54
Author(s):  
Javier Eduardo Fernandez ◽  
Vincent Perreten ◽  
Sybille Schwendener

Abstract Objectives To analyse macrolide resistance in a Macrococcus canis strain isolated from a dog with an ear infection, and determine whether the resistance mechanism is also present in other bacteria, and associated with mobile genetic elements. Methods The whole genome of M. canis Epi0082 was sequenced using PacBio and Illumina technologies. Novel macrolide resistance determinants were identified through bioinformatic analysis, and functionality was demonstrated by expression in Staphylococcus aureus. Mobile genetic elements containing the novel genes were analysed in silico for strain Epi0082 as well as in other bacterial strains deposited in GenBank. Results M. canis Epi0082 contained a 3212 bp operon with the novel macrolide resistance genes mef(F) and msr(G) encoding a efflux protein and an ABC-F ribosomal protection protein, respectively. Cloning in S. aureus confirmed that both genes individually confer resistance to the 14- and 15-membered ring macrolides erythromycin and azithromycin, but not the 16-membered ring macrolide tylosin. A reduced susceptibility to the streptogramin B pristinamycin IA was additionally observed when msr(G) was expressed in S. aureus under erythromycin induction. Epi0082 carried the mef(F)–msr(G) operon together with the chloramphenicol resistance gene fexB in a novel 39 302 bp plasmid pMiCAN82a. The mef(F)–msr(G) operon was also found in macrolide-resistant Macrococcus caseolyticus strains in the GenBank database, but was situated in the chromosome as part of a novel 13 820 bp or 13 894 bp transposon Tn6776. Conclusions The identification of mef(F) and msr(G) on different mobile genetic elements in Macrococcus species indicates that these genes hold potential for further dissemination of resistance to the clinically important macrolides in the bacterial population.


Author(s):  
N.V. Bardukov ◽  
◽  
A.V. Feofilov ◽  
T.T. Glazko ◽  
V.I. Glazko ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pimlapas Leekitcharoenphon ◽  
Markus Hans Kristofer Johansson ◽  
Patrick Munk ◽  
Burkhard Malorny ◽  
Magdalena Skarżyńska ◽  
...  

AbstractThe emergence of antimicrobial resistance (AMR) is one of the biggest health threats globally. In addition, the use of antimicrobial drugs in humans and livestock is considered an important driver of antimicrobial resistance. The commensal microbiota, and especially the intestinal microbiota, has been shown to have an important role in the emergence of AMR. Mobile genetic elements (MGEs) also play a central role in facilitating the acquisition and spread of AMR genes. We isolated Escherichia coli (n = 627) from fecal samples in respectively 25 poultry, 28 swine, and 15 veal calf herds from 6 European countries to investigate the phylogeny of E. coli at country, animal host and farm levels. Furthermore, we examine the evolution of AMR in E. coli genomes including an association with virulence genes, plasmids and MGEs. We compared the abundance metrics retrieved from metagenomic sequencing and whole genome sequenced of E. coli isolates from the same fecal samples and farms. The E. coli isolates in this study indicated no clonality or clustering based on country of origin and genetic markers; AMR, and MGEs. Nonetheless, mobile genetic elements play a role in the acquisition of AMR and virulence genes. Additionally, an abundance of AMR was agreeable between metagenomic and whole genome sequencing analysis for several AMR classes in poultry fecal samples suggesting that metagenomics could be used as an indicator for surveillance of AMR in E. coli isolates and vice versa.


BMC Genomics ◽  
2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Yuan Wu ◽  
Lin Yang ◽  
Wen-Ge Li ◽  
Wen Zhu Zhang ◽  
Zheng Jie Liu ◽  
...  

Abstract Background Clade 5 Clostridioides difficile diverges significantly from the other clades and is therefore, attracting increasing attention due its great heterogeneity. In this study, we used third-generation sequencing techniques to sequence the complete whole genomes of three ST11 C. difficile isolates, RT078 and another two new ribotypes (RTs), obtained from three independent hospitalized elderly patients undergoing antibiotics treatment. Mobile genetic elements (MGEs), antibiotic-resistance, drug resistance genes, and virulent-related genes were analyzed and compared within these three isolates. Results Isolates 10,010 and 12,038 carried a distinct deletion in tcdA compared with isolate 21,062. Furthermore, all three isolates had identical deletions and point-mutations in tcdC, which was once thought to be a unique characteristic of RT078. Isolate 21,062 (RT078) had a unique plasmid, different numbers of transposons and genetic organization, and harboring special CRISPR spacers. All three isolates retained high-level sensitivity to 11 drugs and isolate 21,062 (RT078) carried distinct drug-resistance genes and loss of numerous flagellum-related genes. Conclusions We concluded that capillary electrophoresis based PCR-ribotyping is important for confirming RT078. Furthermore, RT078 isolates displayed specific MGEs, indicating an independent evolutionary process. In the further study, we could testify these findings with more RT078 isolates of divergent origins.


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