scholarly journals Integrase-Controlled Excision of Metal-Resistance Genomic Islands in Acinetobacter baumannii

Genes ◽  
2018 ◽  
Vol 9 (7) ◽  
pp. 366 ◽  
Author(s):  
Zaaima AL-Jabri ◽  
Roxana Zamudio ◽  
Eva Horvath-Papp ◽  
Joseph Ralph ◽  
Zakariya AL-Muharrami ◽  
...  

Genomic islands (GIs) are discrete gene clusters encoding for a variety of functions including antibiotic and heavy metal resistance, some of which are tightly associated to lineages of the core genome phylogenetic tree. We have investigated the functions of two distinct integrase genes in the mobilization of two metal resistant GIs, G08 and G62, of Acinetobacter baumannii. Real-time PCR demonstrated integrase-dependent GI excision, utilizing isopropyl β-d-1-thiogalactopyranoside IPTG-inducible integrase genes in plasmid-based mini-GIs in Escherichia coli. In A. baumannii, integrase-dependent excision of the original chromosomal GIs could be observed after mitomycin C induction. In both E. coli plasmids and A. baumannii chromosome, the rate of excision and circularization was found to be dependent on the expression level of the integrases. Susceptibility testing in A. baumannii strain ATCC 17978, A424, and their respective ΔG62 and ΔG08 mutants confirmed the contribution of the GI-encoded efflux transporters to heavy metal decreased susceptibility. In summary, the data evidenced the functionality of two integrases in the excision and circularization of the two Acinetobacter heavy-metal resistance GIs, G08 and G62, in E. coli, as well as when chromosomally located in their natural host. These recombination events occur at different frequencies resulting in genome plasticity and may participate in the spread of resistance determinants in A. baumannii.

2018 ◽  
Vol 49 (3) ◽  
pp. 471-480 ◽  
Author(s):  
Mudsser Azam ◽  
Arif Tasleem Jan ◽  
Ashutosh Kumar ◽  
Kehkashan Siddiqui ◽  
Aftab Hossain Mondal ◽  
...  

2020 ◽  
Author(s):  
Agnieszka Klonowska ◽  
Lionel Moulin ◽  
Julie Kaye Ardley ◽  
Florence Braun ◽  
Margaret Mary Gollagher ◽  
...  

Abstract Background Cupriavidus strain STM 6070 was isolated from nickel-rich soil collected near Koniambo massif, New Caledonia, using the invasive legume trap host Mimosa pudica. STM 6070 is a heavy metal-tolerant strain that is highly effective at fixing nitrogen with M. pudica. Here we have provided an updated taxonomy for STM 6070 and described salient features of the annotated genome, focusing on heavy metal resistance (HMR) loci and heavy metal efflux (HME) systems.Results The 6,771,773 bp high-quality-draft genome consists of 107 scaffolds containing 6,118 protein-coding genes. ANI values show that STM 6070 is a new species of Cupriavidus. The STM 6070 symbiotic region was syntenic with that of the M. pudica-nodulating Cupriavidus taiwanensis LMG 19424T. In contrast to the nickel and zinc sensitivity of C. taiwanensis strains, STM 6070 grew at high Ni2+ and Zn2+ concentrations. The STM 6070 genome contains 55 genes, located in 12 clusters, that encode HMR structural proteins belonging to the RND, MFS, CHR, ARC3, CDF and P-ATPase protein superfamilies. These HMR molecular determinants are putatively involved in arsenic (ars), chromium (chr), cobalt-zinc-cadmium (czc), copper (cop, cup), nickel (nie and nre), and silver and/or copper (sil) resistance. Seven of these HMR clusters were common to symbiotic and non-symbiotic Cupriavidus species, while four clusters were specific to STM 6070, with three of these being associated with insertion sequences. Within the specific STM 6070 HMR clusters, three novel HME-RND systems (nieIC cep nieBA, czcC2B2A2, and hmxB zneAC zneR hmxS) were identified, which constitute new candidate genes for nickel and zinc resistance.Conclusions STM 6070 belongs to a new Cupriavidus species, for which we have proposed the name Cupriavidus neocaledonicus sp. nov.. STM6070 harbours a pSym with a high degree of gene conservation to the pSyms of M. pudica-nodulating C. taiwanensis strains, probably as a result of recent horizontal transfer. The presence of specific HMR clusters, associated with transposase genes, suggests that the selection pressure of the New Caledonian ultramafic soils has driven the specific adaptation of STM 6070 to heavy-metal-rich soils via horizontal gene transfer.


2020 ◽  
Author(s):  
Agnieszka Klonowska ◽  
Lionel Moulin ◽  
Julie Ardley ◽  
Florence Braun ◽  
Margaret Gollagher ◽  
...  

Abstract Background Cupriavidus strain STM 6070 was isolated from nickel-rich soil collected near Koniambo massif, New Caledonia, using the invasive legume trap host Mimosa pudica. STM 6070 is a heavy metal-tolerant strain that is highly effective at fixing nitrogen with M. pudica. Here we have provided an updated taxonomy for STM 6070 and described salient features of the annotated genome, focusing on heavy metal resistance (HMR) loci and heavy metal efflux (HME) systems.Results The 6,771,773 bp high-quality-draft genome consists of 107 scaffolds containing 6,118 protein-coding genes. ANI values show that STM 6070 is a new species of Cupriavidus. The STM 6070 symbiotic region was syntenic with that of the M. pudica-nodulating Cupriavidus taiwanensis LMG 19424T. In contrast to the nickel and zinc sensitivity of C. taiwanensis strains, STM 6070 grew at high Ni2+ and Zn2+ concentrations. The STM 6070 genome contains 55 genes, located in 12 clusters, that encode HMR structural proteins belonging to the RND, MFS, CHR, ARC3, CDF and P-ATPase protein superfamilies. These HMR molecular determinants are putatively involved in arsenic (ars), chromium (chr), cobalt-zinc-cadmium (czc), copper (cop, cup), nickel (nie and nre), and silver and/or copper (sil) resistance. Seven of these HMR clusters were common to symbiotic and non-symbiotic Cupriavidus species, while four clusters were specific to STM 6070, with three of these being associated with insertion sequences. Within the specific STM 6070 HMR clusters, three novel HME-RND systems (nieIC cep nieBA, czcC2B2A2, and hmxB zneAC zneR hmxS) were identified, which constitute new candidate genes for nickel and zinc resistance.Conclusions STM 6070 belongs to a new Cupriavidus species, for which we have proposed the name Cupriavidus neocaledonicus sp. nov.. STM6070 harbours a pSym with a high degree of gene conservation to the pSyms of M. pudica-nodulating C. taiwanensis strains, probably as a result of recent horizontal transfer. The presence of specific HMR clusters, associated with transposase genes, suggests that the selection pressure of the New Caledonian ultramafic soils has driven the specific adaptation of STM 6070 to heavy-metal-rich soils via horizontal gene transfer.


2020 ◽  
Vol 11 ◽  
Author(s):  
Getahun E. Agga ◽  
John Kasumba ◽  
John H. Loughrin ◽  
Eric D. Conte

Anaerobic digestion is used for the treatment of animal manure by generating biogas. Heavy metals cause environmental pollutions and co-select for antimicrobial resistance. We evaluated the impact of mesophilic anaerobic digestion of cattle manure (CM), swine manure (SM) and poultry litter (PL) on the concentrations of seven tetracycline [tet(A), tet(B), tet(G), tet(M), tet(O), tet(Q), and tet(W)], macrolide [erm(B)], methicillin (mecA and mecC), copper (copB, pcoA, pcoD, and tcrB) and zinc (czrC) resistance genes, and three bacterial species (E. coli, Enterococcus spp. and Staphylococcus aureus). The total bacterial population and total abundance of the seven tet genes significantly increased in the three manure types after digestion. Concentration of tet(M) was strongly correlated with that of erm(B) and enterococci. As concentration of tetracyclines declined during anaerobic digestion, that of four tet genes (A, B, Q, and W) and 16S rRNA increased, that of tet(M) decreased, and that of tet(G) and tet(O) did not change. Concentrations of copB and pcoA did not change; while that of pcoD did not change in the PL, it increased in the SM and CM. While the concentration of enterococci remained unchanged in CM, it significantly increased in the PL and SM. Concentrations of tcrB significantly increased in the three manure types. While concentrations of S. aureus significantly increased in the CM and PL, that of SM was not affected. Concentrations of mecC significantly increased in all manure types after digestion; while mecA concentrations did not change in the SM, they significantly increased in CM and PL. While concentration of czrC remained low in the CM, it increased in the PL but declined in the SM. In conclusion, while mesophilic anaerobic digestion of animal manure decreased concentration of tetracyclines, it increased the concentrations of total bacteria, tet genes, E. coli, enterococci and S. aureus and methicillin resistance genes. It did not have any effect on concentrations of heavy metals; concentrations of heavy metal resistance genes either increased or remained unaffected depending on the animal species. This study showed the need for post-digestion treatments of animal manure to remove bacteria, antibiotic resistance genes, heavy metals and their resistance genes.


2020 ◽  
Author(s):  
Agnieszka Klonowska ◽  
Lionel Moulin ◽  
Julie Ardley ◽  
Florence Braun ◽  
Margaret Gollagher ◽  
...  

Abstract Background Cupriavidus strain STM 6070 was isolated from nickel-rich soil collected near Koniambo massif, New Caledonia, using the invasive legume trap host Mimosa pudica. STM 6070 is a heavy metal-tolerant strain that is highly effective at fixing nitrogen with M. pudica. Here we have provided an updated taxonomy for STM 6070 and described salient features of the annotated genome, focusing on heavy metal resistance (HMR) loci and heavy metal efflux (HME) systems.Results The 6,771,773 bp high-quality-draft genome consists of 107 scaffolds containing 6,118 protein-coding genes. ANI values show that STM 6070 is a new species of Cupriavidus. The STM 6070 symbiotic region was syntenic with that of the M. pudica-nodulating Cupriavidus taiwanensis LMG 19424T. In contrast to the nickel and zinc sensitivity of C. taiwanensis strains, STM 6070 grew at high Ni2+ and Zn2+ concentrations. The STM 6070 genome contains 55 genes, located in 12 clusters, that encode HMR structural proteins belonging to the RND, MFS, CHR, ARC3, CDF and P-ATPase protein superfamilies. These HMR molecular determinants are putatively involved in arsenic (ars), chromium (chr), cobalt-zinc-cadmium (czc), copper (cop, cup), nickel (nie and nre), and silver and/or copper (sil) resistance. Seven of these HMR clusters were common to symbiotic and non-symbiotic Cupriavidus species, while four clusters were specific to STM 6070, with three of these being associated with insertion sequences. Within the specific STM 6070 HMR clusters, three novel HME-RND systems (nieIC cep nieBA, czcC2B2A2, and hmxB zneAC zneR hmxS) were identified, which constitute new candidate genes for nickel and zinc resistance.Conclusions STM 6070 belongs to a new Cupriavidus species, for which we have proposed the name Cupriavidus neocaledonicus sp. nov.. STM6070 harbours a pSym with a high degree of gene conservation to the pSyms of M. pudica-nodulating C. taiwanensis strains, probably as a result of recent horizontal transfer. The presence of specific HMR clusters, associated with transposase genes, suggests that the selection pressure of the New Caledonian ultramafic soils has driven the specific adaptation of STM 6070 to heavy-metal-rich soils via horizontal gene transfer.


2020 ◽  
Author(s):  
Agnieszka Klonowska ◽  
Lionel Moulin ◽  
Julie Ardley ◽  
Florence Braun ◽  
Margaret Gollagher ◽  
...  

Abstract Background Cupriavidus strain STM 6070 was isolated from nickel-rich soil collected near Koniambo massif, New Caledonia, using the invasive legume trap host Mimosa pudica. STM 6070 is a heavy metal-tolerant strain that is highly effective at fixing nitrogen with M. pudica. Here we have provided an updated taxonomy for STM 6070 and described salient features of the annotated genome, focusing on heavy metal resistance (HMR) loci and heavy metal efflux (HME) systems.Results The 6,771,773 bp high-quality-draft genome consists of 107 scaffolds containing 6,118 protein-coding genes. ANI values show that STM 6070 is a new species of Cupriavidus. The STM 6070 symbiotic region was syntenic with that of the M. pudica-nodulating Cupriavidus taiwanensis LMG 19424T. In contrast to the nickel and zinc sensitivity of C. taiwanensis strains, STM 6070 grew at high Ni2+ and Zn2+ concentrations. The STM 6070 genome contains 55 genes, located in 12 clusters, that encode HMR structural proteins belonging to the RND, MFS, CHR, ARC3, CDF and P-ATPase protein superfamilies. These HMR molecular determinants are putatively involved in arsenic (ars), chromium (chr), cobalt-zinc-cadmium (czc), copper (cop, cup), nickel (nie and nre), and silver and/or copper (sil) resistance. Seven of these HMR clusters were common to symbiotic and non-symbiotic Cupriavidus species, while four clusters were specific to STM 6070, with three of these being associated with insertion sequences. Within the specific STM 6070 HMR clusters, three novel HME-RND systems (nieIC cep nieBA, czcC2B2A2, and hmxB zneAC zneR hmxS) were identified, which constitute new candidate genes for nickel and zinc resistance.Conclusions STM 6070 belongs to a new Cupriavidus species, for which we have proposed the name Cupriavidus neocaledonicus sp. nov.. STM6070 harbours a pSym with a high degree of gene conservation to the pSyms of M. pudica-nodulating C. taiwanensis strains, probably as a result of recent horizontal transfer. The presence of specific HMR clusters, associated with transposase genes, suggests that the selection pressure of the New Caledonian ultramafic soils has driven the specific adaptation of STM 6070 to heavy-metal-rich soils via horizontal gene transfer.


2019 ◽  
Vol 8 (40) ◽  
Author(s):  
Zhisong Cui ◽  
Veronika Kivenson ◽  
Na Liu ◽  
Angela Xu ◽  
Xiao Luan ◽  
...  

We present the complete genome sequence of fluoranthene-consuming Cycloclasticus sp. strain PY97N. This strain has one circular chromosome with a G+C content of 42.06%. Moreover, two genomic islands were identified as putative conjugative elements. These genomic details are expected to inform our understanding of the remarkable catabolic capacities of organisms of the Cycloclasticus lineage.


2007 ◽  
Vol 189 (20) ◽  
pp. 7417-7425 ◽  
Author(s):  
Sébastien Monchy ◽  
Mohammed A. Benotmane ◽  
Paul Janssen ◽  
Tatiana Vallaeys ◽  
Safiyh Taghavi ◽  
...  

ABSTRACT We fully annotated two large plasmids, pMOL28 (164 open reading frames [ORFs]; 171,459 bp) and pMOL30 (247 ORFs; 233,720 bp), in the genome of Cupriavidus metallidurans CH34. pMOL28 contains a backbone of maintenance and transfer genes resembling those found in plasmid pSym of C. taiwanensis and plasmid pHG1 of C. eutrophus, suggesting that they belong to a new class of plasmids. Genes involved in resistance to the heavy metals Co(II), Cr(VI), Hg(II), and Ni(II) are concentrated in a 34-kb region on pMOL28, and genes involved in resistance to Ag(I), Cd(II), Co(II), Cu(II), Hg(II), Pb(II), and Zn(II) occur in a 132-kb region on pMOL30. We identified three putative genomic islands containing metal resistance operons flanked by mobile genetic elements, one on pMOL28 and two on pMOL30. Transcriptomic analysis using quantitative PCR and microarrays revealed metal-mediated up-regulation of 83 genes on pMOL28 and 143 genes on pMOL30 that coded for all known heavy metal resistance proteins, some new heavy metal resistance proteins (czcJ, mmrQ, and pbrU), membrane proteins, truncated transposases, conjugative transfer proteins, and many unknown proteins. Five genes on each plasmid were down-regulated; for one of them, chrI localized on pMOL28, the down-regulation occurred in the presence of five cations. We observed multiple cross-responses (induction of specific metal resistance by other metals), suggesting that the cellular defense of C. metallidurans against heavy metal stress involves various regulons and probably has multiple stages, including a more general response and a more metal-specific response.


Genes ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 573 ◽  
Author(s):  
Yuan Li ◽  
Nicolas Carraro ◽  
Nan Yang ◽  
Bixiu Liu ◽  
Xian Xia ◽  
...  

Heavy metals (HMs) are compounds that can be hazardous and impair growth of living organisms. Bacteria have evolved the capability not only to cope with heavy metals but also to detoxify polluted environments. Three heavy metal-resistant strains of Mucilaginibacer rubeus and one of Mucilaginibacter kameinonensis were isolated from the gold/copper Zijin mining site, Longyan, Fujian, China. These strains were shown to exhibit high resistance to heavy metals with minimal inhibitory concentration reaching up to 3.5 mM Cu(II), 21 mM Zn(II), 1.2 mM Cd(II), and 10.0 mM As(III). Genomes of the four strains were sequenced by Illumina. Sequence analyses revealed the presence of a high abundance of heavy metal resistance (HMR) determinants. One of the strain, M. rubeus P2, carried genes encoding 6 putative PIB-1-ATPase, 5 putative PIB-3-ATPase, 4 putative Zn(II)/Cd(II) PIB-4 type ATPase, and 16 putative resistance-nodulation-division (RND)-type metal transporter systems. Moreover, the four genomes contained a high abundance of genes coding for putative metal binding chaperones. Analysis of the close vicinity of these HMR determinants uncovered the presence of clusters of genes potentially associated with mobile genetic elements. These loci included genes coding for tyrosine recombinases (integrases) and subunits of mating pore (type 4 secretion system), respectively allowing integration/excision and conjugative transfer of numerous genomic islands. Further in silico analyses revealed that their genetic organization and gene products resemble the Bacteroides integrative and conjugative element CTnDOT. These results highlight the pivotal role of genomic islands in the acquisition and dissemination of adaptive traits, allowing for rapid adaption of bacteria and colonization of hostile environments.


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