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Gheorghe-Barbu I, Surleac M, Barbu IC, Paraschiv S, Bănică LM, Rotaru LI, Vrâncianu CO, Niță Lazăr M, Oțelea D, Chifiriuc MC. Decoding the resistome, virulome and mobilome of clinical versus aquatic Acinetobacter baumannii in southern Romania. Heliyon 2024; 10:e33372. [PMID: 39035534 PMCID: PMC11259834 DOI: 10.1016/j.heliyon.2024.e33372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 06/19/2024] [Accepted: 06/20/2024] [Indexed: 07/23/2024] Open
Abstract
Acinetobacter baumannii, a notorious opportunistic pathogen, presents a formidable challenge in both clinical and environmental fields due to its resilience and ability to acquire resistance. This study undertook a comprehensive analysis of 183 A. baumannii isolates collected between 2019 and 2022 from intra-hospital infections (IHI), hospital sewages (Hs), wastewater treatment plants (WWTP), and adjacent river waters from two Southern cities, focusing on their resistome, virulome, and mobilome through isolation on chromogenic media, identification by MALDI-TOF-MS and antibiotic susceptibility testing by disk diffusion) followed by genotypic characterization [Whole Genome Sequencing (WGS), 3rd generation sequencing through the MinION (ONT) platform, pangenome description, and respectively horizontal gene transfer through conjugation assays]. Our findings reveal significant genomic plasticity and the prevalence of high-risk international clones, underlining the potential of these isolates to act as reservoirs for antibiotic resistance genes (ARGs) that could be dynamically exchanged between clinical and environmental settings through mobile genetic elements (MGEs) such as the pMAL1 plasmids and the critical role of WWTPs in the persistence and spread of A. baumannii. Moreover, our study presents the first report of the co-occurrence of bla OXA-23 and bla OXA-72 in A. baumannii ST2 clone. Thus, our research underscores the necessity for integrated surveillance and targeted interventions across healthcare and environmental sectors to mitigate the risk posed by this adaptable pathogen.
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Affiliation(s)
- Irina Gheorghe-Barbu
- Department of Microbiology and Botany, Faculty of Biology, University of Bucharest, Bucharest, Romania
- Research Institute of the University of Bucharest, University of Bucharest, Bucharest, Romania
| | - Marius Surleac
- Research Institute of the University of Bucharest, University of Bucharest, Bucharest, Romania
- National Institute for Infectious Diseases, “Matei Balș’‘, Bucharest, Romania
| | - Ilda Czobor Barbu
- Department of Microbiology and Botany, Faculty of Biology, University of Bucharest, Bucharest, Romania
- Research Institute of the University of Bucharest, University of Bucharest, Bucharest, Romania
| | - Simona Paraschiv
- National Institute for Infectious Diseases, “Matei Balș’‘, Bucharest, Romania
| | | | - Liviu-Iulian Rotaru
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Corneliu Ovidiu Vrâncianu
- Department of Microbiology and Botany, Faculty of Biology, University of Bucharest, Bucharest, Romania
- Research Institute of the University of Bucharest, University of Bucharest, Bucharest, Romania
- National Institute of Research and Development for Biological Sciences, 296 Splaiul Independentei, District 6, 060031 Bucharest, Romania
| | - Mihai Niță Lazăr
- National Institute for Research and Development for Industrial Ecology, Bucharest, Romania
| | - Dan Oțelea
- National Institute for Infectious Diseases, “Matei Balș’‘, Bucharest, Romania
| | - Mariana Carmen Chifiriuc
- Department of Microbiology and Botany, Faculty of Biology, University of Bucharest, Bucharest, Romania
- Research Institute of the University of Bucharest, University of Bucharest, Bucharest, Romania
- Romanian Academy, Bucharest, Romania
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Shahar S, Sant KE, Allsing N, Kelley ST. Metagenomic analysis of microbial communities and antibiotic resistant genes in the Tijuana river, and potential sources. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 342:123067. [PMID: 38043772 PMCID: PMC11160352 DOI: 10.1016/j.envpol.2023.123067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 11/02/2023] [Accepted: 11/27/2023] [Indexed: 12/05/2023]
Abstract
The Tijuana River is a transborder river that flows northwest across the border from Baja California in Mexico into Southern California before discharging into the Pacific Ocean. The river is frequently contaminated with raw sewage due to inadequate sanitary infrastructure in Tijuana. To assess the type and degree of microbial contamination, water samples were collected monthly from a near-border and an estuarine site from August 2020 until May 2021. A portion of each sample was used for epifluorescent microscopy and DNA was extracted directly from the rest for shotgun metagenomic sequencing. After sequence quality checking and processing, we used the rapid taxonomic identifier tool Kaiju to characterize the microbial diversity of the metagenomes and matched the sequences against the Comprehensive Antibiotic Resistance Database (CARD) to examine antimicrobial resistance genes (ARGs). Bacterial and viral-like particle (VLP) abundance was consistently higher in the near-border samples than in the estuarine samples, while alpha diversity (within sample biodiversity) was higher in estuarine samples. Beta-diversity analysis found clear compositional separation between samples from the two sites, and the near-border samples were more dissimilar to one another than were the estuarine sites. Near-border samples were dominated by fecal-associated bacteria and bacteria associated with sewage sludge, while estuarine sites were dominated by marine bacteria. ARGs were more abundant at the near-border site, but were also readily detectable in the estuarine samples, and the most abundant ARGs had multi-resistance to beta-lactam antibiotics. SourceTracker analysis identified human feces and sewage sludge to be the largest contributors to the near-border samples, while marine waters dominated estuarine samples except for two sewage overflow dates with high fecal contamination. Overall, our research determined human sewage microbes to be common in the Tijuana River, and the prevalence of ARGs confirms the importance of planned infrastructure treatment upgrades for environmental health.
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Affiliation(s)
- Shayla Shahar
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Karilyn E Sant
- School of Public Health, San Diego State University, San Diego, CA 92182, USA
| | - Nicholas Allsing
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Scott T Kelley
- Department of Biology, San Diego State University, San Diego, CA 92182, USA.
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Stehling EG, Sellera FP, de Almeida OGG, Gonzalez IHL, Ramos PL, da Rosa-Garzon NG, von Zeska Kress MR, Cabral H, Furlan JPR. Genomic features and comparative analysis of a multidrug-resistant Acinetobacter bereziniae strain infecting an animal: a novel emerging one health pathogen? World J Microbiol Biotechnol 2024; 40:63. [PMID: 38190002 DOI: 10.1007/s11274-023-03867-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 12/04/2023] [Indexed: 01/09/2024]
Abstract
Acinetobacter bereziniae has recently gained medical notoriety due to its emergence as a multidrug resistance and healthcare-associated pathogen. In this study, we report the whole-genome characterization of an A. bereziniae strain (A321) recovered from an infected semiaquatic turtle, as well as a comparative analysis of A. bereziniae strains circulating at the human-animal-environment interface. Strain A321 displayed a multidrug resistance profile to medically important antimicrobials, which was supported by a wide resistome. The novel Tn5393m transposon and a qnrB19-bearing ColE1-like plasmid were identified in A321 strain. Novel OXA-229-like β-lactamases were detected and expression of OXA-931 demonstrated a 2-64-fold increase in the minimum inhibitory concentration for β-lactam agents. Comparative genomic analysis revealed that most A. bereziniae strains did not carry any antimicrobial resistance genes (ARGs); however, some strains from China, Brazil, and India harbored six or more ARGs. Furthermore, A. bereziniae strains harbored conserved virulence genes. These results add valuable information regarding the spread of ARGs and mobile genetic elements that could be shared not only between A. bereziniae but also by other bacteria of clinical interest. This study also demonstrates that A. bereziniae can spill over from anthropogenic sources into natural environments and subsequently be transmitted to non-human hosts, making this a potential One Health bacteria that require close surveillance.
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Affiliation(s)
- Eliana Guedes Stehling
- Department of Clinical Analyses, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, São Paulo, Brazil
| | - Fábio P Sellera
- Department of Internal Medicine, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
- School of Veterinary Medicine, Metropolitan University of Santos, Santos, Brazil
| | - Otávio Guilherme Gonçalves de Almeida
- Department of Clinical Analyses, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, São Paulo, Brazil
| | - Irys Hany Lima Gonzalez
- Coordination of Wild Fauna, Secretary of Environment, Infrastructure and Logistics, São Paulo, Brazil
| | - Patrícia Locosque Ramos
- Coordination of Wild Fauna, Secretary of Environment, Infrastructure and Logistics, São Paulo, Brazil
| | - Nathália Gonsales da Rosa-Garzon
- Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, São Paulo, Brazil
| | - Marcia Regina von Zeska Kress
- Department of Clinical Analyses, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, São Paulo, Brazil
| | - Hamilton Cabral
- Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, São Paulo, Brazil
| | - João Pedro Rueda Furlan
- Department of Clinical Analyses, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, São Paulo, Brazil.
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Tian C, Song J, Ren L, Huang D, Wang S, Fu L, Zhao Y, Bai Y, Fan X, Ma T, Ying J. Complete genetic characterization of carbapenem-resistant Acinetobacter johnsonii, co-producing NDM-1, OXA-58, and PER-1 in a patient source. Front Cell Infect Microbiol 2023; 13:1227063. [PMID: 37692162 PMCID: PMC10486904 DOI: 10.3389/fcimb.2023.1227063] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 07/31/2023] [Indexed: 09/12/2023] Open
Abstract
The emergence of carbapenemase-producing Acinetobacter spp. has been widely reported and become a global threat. However, carbapenem-resistant A. johnsonii strains are relatively rare and without comprehensive genetic structure analysis, especially for isolates collected from human specimen. Here, one A. johnsonii AYTCM strain, co-producing NDM-1, OXA-58, and PER-1 enzymes, was isolated from sputum in China in 2018. Antimicrobial susceptibility testing showed that it was resistant to meropenem, imipenem, ceftazidime, ciprofloxacin, and cefoperazone/sulbactam. Whole-genome sequencing and bioinformatic analysis revealed that it possessed 11 plasmids. bla OXA-58 and bla PER-1 genes were located in the pAYTCM-1 plasmid. Especially, a complex class 1 integron consisted of a 5' conserved segment (5' CS) and 3' CS, which was found to carry sul1, arr-3, qnrVC6, and bla PER-1 cassettes. Moreover, the bla NDM-1 gene was located in 41,087 conjugative plasmids and was quite stable even after 70 passages under antibiotics-free conditions. In addition, six prophage regions were identified. Tracking of closely related plasmids in the public database showed that pAYTCM-1 was similar to pXBB1-9, pOXA23_010062, pOXA58_010030, and pAcsw19-2 plasmids, which were collected from the strains of sewage in China. Concerning the pAYTCM-3 plasmids, results showed that strains were collected from different sources and their hosts were isolated from various countries, such as China, USA, Japan, Brazil, and Mexico, suggesting that a wide spread occurred all over the world. In conclusion, early surveillance is warranted to avoid the extensive spread of this high-risk clone in the healthcare setting.
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Affiliation(s)
- Chongmei Tian
- Department of Pharmacy, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, Zhejiang, China
| | - Jianqin Song
- Department of Traditional Chinese Medicine, Hangzhou Linping District Hospital of Integrated Chinese and Western Medicine, Hangzhou, China
| | - Lingzhi Ren
- Department of Clinical Laboratory, The People’s Hospital of Zhangqiu Area, Jinan, China
| | - Delian Huang
- School of Medical Technology and Information Engineering, Zhejiang Chinese Medical University, Hangzhou, China
| | - Siwei Wang
- Core Facility, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People’s Hospital, Quzhou, China
| | - Liping Fu
- Department of Pharmacy, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, Zhejiang, China
| | - Yaping Zhao
- Department of Pharmacy, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, Zhejiang, China
| | - Yongfeng Bai
- Department of Clinical Laboratory, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People’s Hospital, Quzhou, China
| | - Xueyu Fan
- Department of Clinical Laboratory, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People’s Hospital, Quzhou, China
| | - Tianhong Ma
- Department of Pharmacy, Jiaxing Hospital of Traditional Chinese Medicine, Jiaxing, China
| | - Junjie Ying
- Department of Urology, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People’s Hospital, Quzhou, China
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Sheck E, Romanov A, Shapovalova V, Shaidullina E, Martinovich A, Ivanchik N, Mikotina A, Skleenova E, Oloviannikov V, Azizov I, Vityazeva V, Lavrinenko A, Kozlov R, Edelstein M. Acinetobacter Non- baumannii Species: Occurrence in Infections in Hospitalized Patients, Identification, and Antibiotic Resistance. Antibiotics (Basel) 2023; 12:1301. [PMID: 37627721 PMCID: PMC10451542 DOI: 10.3390/antibiotics12081301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 08/05/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
BACKGROUND Acinetobacter species other than A. baumannii are becoming increasingly more important as opportunistic pathogens for humans. The primary aim of this study was to assess the prevalence, species distribution, antimicrobial resistance patterns, and carbapenemase gene content of clinical Acinetobacter non-baumannii (Anb) isolates that were collected as part of a sentinel surveillance program of bacterial infections in hospitalized patients. The secondary aim was to evaluate the performance of MALDI-TOF MS systems for the species-level identification of Anb isolates. METHODS Clinical bacterial isolates were collected from multiple sites across Russia and Kazakhstan in 2016-2022. Species identification was performed by means of MALDI-TOF MS, with the Autobio and Bruker systems used in parallel. The PCR detection of the species-specific blaOXA-51-like gene was used as a means of differentiating A. baumannii from Anb species, and the partial sequencing of the rpoB gene was used as a reference method for Anb species identification. The susceptibility of isolates to antibiotics (amikacin, cefepime, ciprofloxacin, colistin, gentamicin, imipenem, meropenem, sulbactam, tigecycline, tobramycin, and trimethoprim-sulfamethoxazole) was determined using the broth microdilution method. The presence of the most common in Acinetobacter-acquired carbapenemase genes (blaOXA-23-like, blaOXA-24/40-like, blaOXA-58-like, blaNDM, blaIMP, and blaVIM) was assessed using real-time PCR. RESULTS In total, 234 isolates were identified as belonging to 14 Anb species. These comprised 6.2% of Acinetobacter spp. and 0.7% of all bacterial isolates from the observations. Among the Anb species, the most abundant were A. pittii (42.7%), A. nosocomialis (13.7%), the A. calcoaceticus/oleivorans group (9.0%), A. bereziniae (7.7%), and A. geminorum (6.0%). Notably, two environmental species, A. oleivorans and A. courvalinii, were found for the first time in the clinical samples of patients with urinary tract infections. The prevalence of resistance to different antibiotics in Anb species varied from <4% (meropenem and colistin) to 11.2% (gentamicin). Most isolates were susceptible to all antibiotics; however, sporadic isolates of A. bereziniae, A. johnsonii, A. nosocomialis, A. oleivorans, A. pittii, and A. ursingii were resistant to carbapenems. A. bereziniae was more frequently resistant to sulbactam, aminoglycosides, trimethoprim-sulfamethoxazole, and tigecycline than the other species. Four (1.7%) isolates of A. bereziniae, A. johnsonii, A. pittii were found to carry carbapenemase genes (blaOXA-58-like and blaNDM, either alone or in combination). The overall accuracy rates of the species-level identification of Anb isolates with the Autobio and Bruker systems were 80.8% and 88.5%, with misidentifications occurring in 5 and 3 species, respectively. CONCLUSIONS This study provides important new insights into the methods of identification, occurrence, species distribution, and antibiotic resistance traits of clinical Anb isolates.
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Affiliation(s)
- Eugene Sheck
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
| | - Andrey Romanov
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
| | - Valeria Shapovalova
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
| | - Elvira Shaidullina
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
| | - Alexey Martinovich
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
| | - Natali Ivanchik
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
| | - Anna Mikotina
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
| | - Elena Skleenova
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
| | - Vladimir Oloviannikov
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
| | - Ilya Azizov
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
| | - Vera Vityazeva
- Republican Children’s Hospital, 185000 Petrozavodsk, Republic of Karelia, Russia
| | - Alyona Lavrinenko
- Shared Resource Laboratory, Karaganda Medical University, 100008 Karaganda, Kazakhstan
| | - Roman Kozlov
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
| | - Mikhail Edelstein
- Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, 214019 Smolensk, Russia; (E.S.); (I.A.)
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Harmer CJ, Pong CH, Hall RM. Insertion sequences related to ISAjo2 target p dif and dif sites and belong to a new IS family, the IS 1202 family. Microb Genom 2023; 9. [PMID: 36880881 PMCID: PMC10132070 DOI: 10.1099/mgen.0.000953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023] Open
Abstract
Several insertion sequences (IS) found in various Acinetobacter species exhibit target specificity. They are found, in the same orientation, 5 bp from the XerC binding site of the pdif sites associated with dif modules in Acinetobacter plasmids, and searches revealed they are also found near chromosomal dif sites of Acinetobacter species. These IS are 1.5 kb long, bounded by 24-26 bp imperfect terminal inverted repeats (TIRs) and encode a large transposase of 441-457 aa. They generate 5 bp target site duplications (TSDs). Structural predictions of the ISAjo2 transposase, TnpAjo2, modelled on TnsB of Tn7 revealed two N-terminal HTH domains followed by an RNaseH fold (DDE domain), a β barrel and a C-terminal domain. Similar to Tn7, the outer IS ends are 5'-TGT and ACA-3', and an additional Tnp binding site, corresponding to the internal portion of the IR, is found near each end. However, the Acinetobacter IS do not encode further proteins related to those required by Tn7 for targeted transposition, and the transposase may interact directly with XerC bound to a dif-like site. We propose that these IS, currently in the IS1202 group in the not characterized yet (NCY) category in ISFinder, are part of a distinct IS1202 family. Other IS listed as in the IS1202 group encode transposases related to TnpAjo2 (25-56 % amino acid identity) and have similar TIRs but fall into three groups based on the TSD length (3-5, >15, 0 bp). Those with 3-5 bp TSDs may also target dif-like sites but targets were not found for the other groups.
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Affiliation(s)
- Christopher J Harmer
- School of Life and Environmental Sciences, The University of Sydney, NSW 2006, Australia
| | - Carol H Pong
- School of Life and Environmental Sciences, The University of Sydney, NSW 2006, Australia
| | - Ruth M Hall
- School of Life and Environmental Sciences, The University of Sydney, NSW 2006, Australia
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Idowu GA, Olalemi AO, Ileke KD. COVID-19 face masks attracted Cellulomonas and Acinetobacter bacteria and provided breeding haven for red cotton bug (Dysdercus suturellus) and house cricket (Acheta domesticus). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:23510-23526. [PMID: 36327070 PMCID: PMC9631651 DOI: 10.1007/s11356-022-23865-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
This study investigated the possibility of COVID-19 medical face masks to affect bacterial and macrofaunal communities in open soil environment. An estimated 1.24 trillion of face masks have been used and discarded as a result of the COVID-19 pandemic, with a significant part of this ending up in the soil environment, where they degrade gradually over time. Because bacteria and macrofauna are sensitive indicators of changes in soil ecosystem, we investigated possible impacts of face masks on population, distribution, and diversity of these soil species. Effect on soil bacterial community was studied by both culture-based and advanced molecular (metagenomics) approach, while impact on macrofauna was investigated by examining monoliths around heap of masks for soil insects. In both cases, control soil experiments without face masks were also set up and monitored over a period of 48 weeks. The study found that the presence of face masks led to a more diverse bacterial community, although no influence on overall bacterial population was evidenced. More importantly, bacteria belonging to the genera Cellulomonas and Acinetobacter were found prominently around face masks and are believed to be involved in biodegradation of the masks. The bacterial community around the masks was dominated by Proteobacteria (29.7-38.7%), but the diversity of species increased gradually with time. Tiny black ants (Monomorium invidium) were attracted to the face masks to take advantage of water retained by the masks during the period of little rainfall. The heaps of face masks also provided shelter and breeding "haven" for soil insects, notably the red cotton bug (Dysdercus suturellus) and house cricket (Acheta domesticus), thereby impacting positively on the population of insect species in the environment. This study provides insights into the actual impacts of face masks on soil organisms under normal outdoor environmental conditions.
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Affiliation(s)
- Gideon Aina Idowu
- Department of Chemistry, School of Physical Sciences, Federal University of Technology Akure, P. M. B. 704, Akure, Ondo State, Nigeria.
| | - Adewale Oluwasogo Olalemi
- Department of Microbiology, School of Life Sciences, Federal University of Technology Akure, Ondo State, Nigeria
| | - Kayode David Ileke
- Department of Biology, School of Life Sciences, Federal University of Technology Akure, Ondo State, Nigeria
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Zhang M, Yu Y, Wang Q, Chen R, Wang Y, Bai Y, Song Z, Lu X, Hao Y. Conjugation of plasmid harboring bla NDM-1 in a clinical Providencia rettgeri strain through the formation of a fusion plasmid. Front Microbiol 2023; 13:1071385. [PMID: 36687647 PMCID: PMC9845711 DOI: 10.3389/fmicb.2022.1071385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 12/07/2022] [Indexed: 01/06/2023] Open
Abstract
Providencia rettgeri has recently gained increased importance owing to the New Delhi metallo-β-lactamase (NDM) and other β-lactamases produced by its clinical isolates. These enzymes reduce the efficiency of antimicrobial therapy. Herein, we reported the findings of whole-genome sequence analysis and a comprehensive pan-genome analysis performed on a multidrug-resistant P. rettgeri 18004577 clinical strain recovered from the urine of a hospitalized patient in Shandong, China, in 2018. Providencia rettgeri 18004577 was found to have a genome assembly size of 4.6 Mb with a G + C content of 41%; a circular plasmid p18004577_NDM of 273.3 Kb, harboring an accessory multidrug-resistant region; and a circular, stable IncT plasmid p18004577_Rts of 146.2 Kb. Additionally, various resistance genes were identified in its genome, including bla NDM-1, bla OXA-10, bla PER-4, aph(3')-VI, ant(2'')-Ia, ant(3')-Ia, sul1, catB8, catA1, mph(E), and tet. Conjugation experiments and whole-genome sequencing revealed that the bla NDM-1 gene could be transferred to the transconjugant via the formation of pJ18004577_NDM, a novel hybrid plasmid. Based on the genetic comparison, the main possible formation process for pJ18004577_NDM was the insertion of the [ΔISKox2-IS26-ΔISKox2]-aph(3')-VI-bla NDM-1 translocatable unit module from p18004577_NDM into plasmid p18004577_Rts in the Russian doll insertion structure (ΔISKox2-IS26-ΔISKox2), which played a role similar to that of IS26 using the "copy-in" route in the mobilization of [aph(3')-VI]-bla NDM-1. The array, multiplicity, and diversity of the resistance and virulence genes in this strain necessitate stringent infection control, antibiotic stewardship, and periodic resistance surveillance/monitoring policies to preempt further horizontal and vertical spread of the resistance genes. Roary analysis based on 30 P. rettgeri strains pan genome identified 415 core, 756 soft core, 5,744 shell, and 12,967 cloud genes, highlighting the "close" nature of P. rettgeri pan-genome. After a comprehensive pan-genome analysis, representative biological information was revealed that included phylogenetic distances, presence or absence of genes across the P. rettgeri bacteria clade, and functional distribution of proteins. Moreover, pan-genome analysis has been shown to be an effective approach to better understand P. rettgeri bacteria because it helps develop various tailored therapeutic strategies based on their biological similarities and differences.
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Affiliation(s)
- Meng Zhang
- Department of Clinical Laboratory, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China,Department of Clinical Laboratory, Liaocheng Second People’s Hospital, Liaocheng, Shandong, China
| | - Yanhua Yu
- Department of Clinical Laboratory, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Qian Wang
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Ran Chen
- Department of Clinical Laboratory, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Yueling Wang
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Yuanyuan Bai
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Zhen Song
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Xinglun Lu
- Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Yingying Hao
- Department of Clinical Laboratory, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China,Department of Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China,*Correspondence: Yingying Hao,
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9
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Hendrickx APA, Schade RP, Landman F, Bosch T, Schouls LM, van Dijk K. Comparative analysis of IMP-4- and OXA-58-containing plasmids of three carbapenemase-producing Acinetobacter ursingii strains in the Netherlands. J Glob Antimicrob Resist 2022; 31:207-211. [PMID: 36184039 DOI: 10.1016/j.jgar.2022.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 09/10/2022] [Accepted: 09/15/2022] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVES A recent occurrence of carbapenemase-producing Acinetobacter ursingii was reported in the Netherlands and comprised three unrelated strains carrying the blaIMP-4 and blaOXA-58 encoding genes. The objective was to investigate a putative common source of the carbapenemase resistance genes and plasmids in these A. ursingii strains. METHODS Hybrid assembly of short-read and long-read sequencing data was performed using Unicycler and assembled genomes were analysed by ResFinder and PlasmidFinder. RESULTS Hybrid assemblies of A. ursingii genomes yielded a circular chromosome, a large plasmid harboring blaIMP-4 and blaOXA-58 genes (sizes 259-317kb), and four to five other smaller plasmids. ResFinder analyses revealed 16 other acquired resistance genes on the plasmids carrying the blaIMP-4 and blaOXA-58 genes. These 18 genes encode resistance towards eight antibiotic classes. The smaller plasmids did not carry acquired resistance genes. Comparative analysis showed that the three blaIMP-4/blaOXA-58 plasmids were similar (61%-83%) and shared 13 to 17 of the 18 resistance genes. BLAST analysis showed that the blaIMP-4/blaOXA-58 plasmids were not reported before. However, a close match with a 399 kb plasmid from Acinetobacter johnsonii was found (99% similarity, 80% coverage). This A. johnsonii plasmid contains the blaOXA-58 gene, but lacks blaIMP-4, and it shares eight other resistance genes with those present on the A. ursingii blaIMP-4/blaOXA-58 plasmids. CONCLUSION Three blaIMP-4/blaOXA-58-carrying plasmids were characterized in three carbapenemase-producing A. ursingii strains. The plasmids were highly similar, suggesting a putative common source or co-selection of resistance genes from A. johnsonii. These results provide initial insights in the dissemination of carbapenem-resistance in A. ursingii in the Netherlands.
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Affiliation(s)
- Antoni P A Hendrickx
- Centre for Infectious Diseases Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands.
| | - Rogier P Schade
- Department of Medical Microbiology and Infection Control, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Fabian Landman
- Centre for Infectious Diseases Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Thijs Bosch
- Centre for Infectious Diseases Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Leo M Schouls
- Centre for Infectious Diseases Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Karin van Dijk
- Department of Medical Microbiology and Infection Control, Amsterdam University Medical Centers, Amsterdam, The Netherlands
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10
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Jia J, Xue X, Guan Y, Fan X, Wang Z. Biofilm characteristics and transcriptomic profiling of Acinetobacter johnsonii defines signatures for planktonic and biofilm cells. ENVIRONMENTAL RESEARCH 2022; 213:113714. [PMID: 35718162 DOI: 10.1016/j.envres.2022.113714] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 06/11/2022] [Accepted: 06/14/2022] [Indexed: 06/15/2023]
Abstract
Most bacteria in the natural environment have a biofilm mode of life, which is intrinsically tolerant to antibiotics. While until now, the knowledge of biofilm formation by Acinetobacter johnsonii is not well understood. In this study, the characteristics and the effect of a sub-inhibitory concentration of antibiotic on A. johnsonii biofilm and planktonic cells were determined. We discovered a positive relationship between biofilm formation and tetracycline resistance, and biofilms rapidly evolve resistance to tetracycline they are treated with. Persister cells commonly exist in both planktonic and biofilm cells, with a higher frequency in the latter. Further transcriptomic analysis speculates that the overexpression of multidrug resistance genes and stress genes were mainly answered to sub lethal concentration of tetracycline in planktonic cells, and the lower metabolic levels after biofilm formation result in high resistance level of biofilm cells to tetracycline. Altogether, these data suggest that A. johnsonii can adjust its phenotype when grown as biofilm and change its metabolism under antibiotic stress, and provide implications for subsequent biofilm control.
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Affiliation(s)
- Jia Jia
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xue Xue
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yongjing Guan
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xiaoteng Fan
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Zaizhao Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China.
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11
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Plasmids as Key Players in Acinetobacter Adaptation. Int J Mol Sci 2022; 23:ijms231810893. [PMID: 36142804 PMCID: PMC9501444 DOI: 10.3390/ijms231810893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 11/17/2022] Open
Abstract
This review briefly summarizes the data on the mechanisms of development of the adaptability of Acinetobacters to various living conditions in the environment and in the clinic. A comparative analysis of the genomes of free-living and clinical strains of A. lwoffii, as well as the genomes of A. lwoffii and A. baumannii, has been carried out. It has been shown that plasmids, both large and small, play a key role in the formation of the adaptability of Acinetobacter to their living conditions. In particular, it has been demonstrated that the plasmids of various strains of Acinetobacter differ from each other in their structure and gene composition depending on the lifestyle of their host bacteria. Plasmids of modern strains are enriched with antibiotic-resistant genes, while the content of genes involved in resistance to heavy metals and arsenic is comparable to plasmids from modern and ancient strains. It is concluded that Acinetobacter plasmids may ensure the survival of host bacteria under conditions of various types of environmental and clinical stresses. A brief overview of the main mechanisms of horizontal gene transfer on plasmids inherent in Acinetobacter strains is also given.
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12
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Gheorghe-Barbu I, Barbu IC, Popa LI, Pîrcălăbioru GG, Popa M, Măruțescu L, Niță-Lazar M, Banciu A, Stoica C, Gheorghe Ș, Lucaciu I, Săndulescu O, Paraschiv S, Surleac M, Talapan D, Muntean AA, Preda M, Muntean MM, Dragomirescu CC, Popa MI, Oțelea D, Chifiriuc MC. Temporo-spatial variations in resistance determinants and clonality of Acinetobacter baumannii and Pseudomonas aeruginosa strains from Romanian hospitals and wastewaters. Antimicrob Resist Infect Control 2022; 11:115. [PMID: 36104761 PMCID: PMC9476303 DOI: 10.1186/s13756-022-01156-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 08/26/2022] [Indexed: 11/10/2022] Open
Abstract
Background Romania is one of the European countries reporting very high antimicrobial resistance (AMR) rates and consumption of antimicrobials. We aimed to characterize the AMR profiles and clonality of 304 multi-drug resistant (MDR) Acinetobacter baumannii (Ab) and Pseudomonas aeruginosa (Pa) strains isolated during two consecutive years (2018 and 2019) from hospital settings, hospital collecting sewage tanks and the receiving wastewater treatment plants (WWTPs) located in the main geographical regions of Romania. Methods The strains were isolated on chromogenic media and identified by MALDI-TOF-MS. Antibiotic susceptibility testing and confirmation of ESBL- and CP- producing phenotypes and genotypes were performed. The genetic characterization also included horizontal gene transfer experiments, whole-genome sequencing (WGS), assembling, annotation and characterization.
Results Both clinical and aquatic isolates exhibited high MDR rates, especially the Ab strains isolated from nosocomial infections and hospital effluents. The phenotypic resistance profiles and MDR rates have largely varied by sampling point and geographic location. The highest MDR rates in the aquatic isolates were recorded in Galați WWTP, followed by Bucharest. The Ab strains harbored mostly blaOXA-23, blaOXA-24, blaSHV, blaTEM and blaGES, while Pa strains blaIMP, blaVIM, blaNDM, blaVEB, blaGES and blaTEM, with high variations depending on the geographical zone and the sampling point. The WGS analysis revealed the presence of antibiotic resistance genes (ARGs) to other antibiotic classes, such as aminoglycosides, tetracyclines, sulphonamides, fosfomycin, phenicols, trimethoprim-sulfamethoxazole as well as class 1 integrons. The molecular analyses highlighted: (i) The presence of epidemic clones such as ST2 for Ab and ST233 and ST357 for Pa; (ii) The relatedness between clinical and hospital wastewater strains and (iii) The possible dissemination of clinical Ab belonging to ST2 (also proved in the conjugation assays for blaOXA-23 or blaOXA-72 genes), ST79 and ST492 and of Pa strains belonging to ST357, ST640 and ST621 in the wastewaters. Conclusion Our study reveals the presence of CP-producing Ab and Pa in all sampling points and the clonal dissemination of clinical Ab ST2 strains in the wastewaters. The prevalent clones were correlated with the presence of class 1 integrons, suggesting that these isolates could be a significant reservoir of ARGs, being able to persist in the environment. Supplementary Information The online version contains supplementary material available at 10.1186/s13756-022-01156-1.
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13
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Sanseverino I, Gómez L, Navarro A, Cappelli F, Niegowska M, Lahm A, Barbiere M, Porcel-Rodríguez E, Valsecchi S, Pedraccini R, Crosta S, Lettieri T. Holistic approach to chemical and microbiological quality of aquatic ecosystems impacted by wastewater effluent discharges. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 835:155388. [PMID: 35489490 DOI: 10.1016/j.scitotenv.2022.155388] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 04/14/2022] [Accepted: 04/15/2022] [Indexed: 06/14/2023]
Abstract
Wastewater treatment plants (WWTPs) collect wastewater from various sources and use different treatment processes to reduce the load of pollutants in the environment. Since the removal of many chemical pollutants and bacteria by WWTPs is incomplete, they constitute a potential source of contaminants. The continuous release of contaminants through WWTP effluents can compromise the health of the aquatic ecosystems, even if they occur at very low concentrations. The main objective of this work was to characterize, over a period of four months, the treatment steps starting from income to the effluent and 5 km downstream to the receiving river. In this context, the efficiency removal of chemical pollutants (e.g. hormones and pharmaceuticals, including antibiotics) and bacteria was assessed in a WWTP case study by using a holistic approach. It embraces different chemical and biological-based methods, such as pharmaceutical analysis by HPLC-MSMS, growth rate inhibition in algae, ligand binding estrogen receptor assay, microbial community study by 16S and shotgun sequencing along with relative quantification of resistance genes by quantitative polymerase chain reaction. Although both, chemical and biological-based methods showed a significant reduction of the pollutant burden in effluent and surface waters compared to the influent of the WWTP, no complete removal of pollutants, pathogens and antibiotic resistance genes was observed.
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Affiliation(s)
| | - Livia Gómez
- European Commission, Joint Research Centre (JRC), I-21027 Ispra, VA, Italy
| | - Anna Navarro
- European Commission, Joint Research Centre (JRC), I-21027 Ispra, VA, Italy
| | - Francesca Cappelli
- Water Research Institute IRSA-CNR, Via del Mulino 19, Brugherio 20861, MB, Italy; University of Insubria, Department of Science and High Technology, Via Valleggio 11, 22100 Como, Italy
| | | | - Armin Lahm
- Bioinformatics Project Support, P.zza S.M. Liberatrice 18, 00153 Roma, Italy
| | - Maurizio Barbiere
- European Commission, Joint Research Centre (JRC), I-21027 Ispra, VA, Italy
| | | | - Sara Valsecchi
- Water Research Institute IRSA-CNR, Via del Mulino 19, Brugherio 20861, MB, Italy
| | | | | | - Teresa Lettieri
- European Commission, Joint Research Centre (JRC), I-21027 Ispra, VA, Italy.
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14
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Li Y, Qiu Y, Gao Y, Chen W, Li C, Dai X, Zhang L. Genetic and virulence characteristics of a Raoultella planticola isolate resistant to carbapenem and tigecycline. Sci Rep 2022; 12:3858. [PMID: 35264602 PMCID: PMC8907287 DOI: 10.1038/s41598-022-07778-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 02/16/2022] [Indexed: 01/29/2023] Open
Abstract
Raoultella planticola is an emerging pathogen causing several infections in humans, and its roles in the propagation of antibiotic resistance genes (ARGs) remain uncharacterized. In this study, a carbapenem and tigecycline-resistant R. planticola isolate was recovered from hospital sewage. It carried nine plasmids, bearing 30 ARGs, including one blaKPC-2 and two blaNDM-1. It also contained a plasmid-borne efflux pump gene cluster, tmexCD1-toprJ, conferring resistance to tigecycline. Analysis of plasmid sequences revealed that both blaNDM-1-carrying plasmids were highly similar to those recovered from humans, reinforcing the close relatedness of environmental and clinical isolates. We also identified that plasmid bearing blaNDM-1 or tmexCD1-toprJ1 was transferable, and can be stabilized in the host bacteria, indicating that the R. planticola isolate has a considerable potential in the dissemination of ARGs. Besides, we found that this isolate could produce biofilm and was virulent in a Galleria mellonella infection model. In conclusion, our study shows the convergence of virulence and multidrug resistance in a R. planticola isolate. This potentially virulent superbug may disseminate into its receiving rivers, and finally to humans through cross-contamination during recreation activities or daily use of water, which poses a risk to public health.
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Affiliation(s)
- Ying Li
- The School of Basic Medical Science and Public Center of Experimental Technology, Southwest Medical University, Luzhou, 646000, Sichuan Province, China
| | - Yichuan Qiu
- The School of Basic Medical Science and Public Center of Experimental Technology, Southwest Medical University, Luzhou, 646000, Sichuan Province, China
| | - Yan Gao
- The School of Basic Medical Science and Public Center of Experimental Technology, Southwest Medical University, Luzhou, 646000, Sichuan Province, China
| | - Wenbi Chen
- The School of Basic Medical Science and Public Center of Experimental Technology, Southwest Medical University, Luzhou, 646000, Sichuan Province, China
| | - Chengwen Li
- The School of Basic Medical Science and Public Center of Experimental Technology, Southwest Medical University, Luzhou, 646000, Sichuan Province, China
| | - Xiaoyi Dai
- The School of Basic Medical Science and Public Center of Experimental Technology, Southwest Medical University, Luzhou, 646000, Sichuan Province, China
| | - Luhua Zhang
- The School of Basic Medical Science and Public Center of Experimental Technology, Southwest Medical University, Luzhou, 646000, Sichuan Province, China.
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15
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Jia J, Liu M, Feng L, Wang Z. Comparative genomic analysis reveals the evolution and environmental adaptation of Acinetobacter johnsonii. Gene 2022; 808:145985. [PMID: 34600047 DOI: 10.1016/j.gene.2021.145985] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 09/07/2021] [Accepted: 09/27/2021] [Indexed: 11/04/2022]
Abstract
Genome plasticity is a key determinant that Acinetobacter johnsonii could widely distribute in natural and clinical environments. However, little attention has been paid to figure out the changes in the genome during A. johnsonii's evolution. Here, a comparative genomic analysis of A. johnsonii isolated from clinical and environmental sources was conducted. In this study, we found A. johnsonii has an open pan-genome and has great adaptability to different environments. Based on the results of the phylogenetic tree, ANI value and the distribution of accessory genes, we found that strains from the same habitat had a high degree of similarity. Though genes associated with the fundamental process were mostly conserved in evolution, clinical-derived isolates accumulate more genes associated with translational modification, β-lactamase and defense mechanisms, whereas environmental-derived isolates enriched more genes related to substances degradation. In addition, clinical-derived strains harbored some "strong" virulence islands and resistance islands. This study highlights the evolutionary relationship of A. johnsonii isolates from clinical and environmental sources.
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Affiliation(s)
- Jia Jia
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Mengyu Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Leilei Feng
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Zaizhao Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China.
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16
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Mindlin S, Maslova O, Beletsky A, Nurmukanova V, Zong Z, Mardanov A, Petrova M. Ubiquitous Conjugative Mega-Plasmids of Acinetobacter Species and Their Role in Horizontal Transfer of Multi-Drug Resistance. Front Microbiol 2021; 12:728644. [PMID: 34621254 PMCID: PMC8490738 DOI: 10.3389/fmicb.2021.728644] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 08/25/2021] [Indexed: 02/05/2023] Open
Abstract
Conjugative mega-plasmids play a special role in adaptation since they carry a huge number of accessory genes, often allowing the host to develop in new niches. In addition, due to conjugation they are able to effectively spread themselves and participate in the transfer of small mobilizable plasmids. In this work, we present a detailed characterization of a recently discovered family of multiple-drug resistance mega-plasmids of Acinetobacter species, termed group III-4a. We describe the structure of the plasmid backbone region, identify the rep gene and the origin of plasmid replication, and show that plasmids from this group are able not only to move between different Acinetobacter species but also to efficiently mobilize small plasmids containing different mob genes. Furthermore, we show that the population of natural Acinetobacter strains contains a significant number of mega-plasmids and reveal a clear correlation between the living conditions of Acinetobacter strains and the structure of their mega-plasmids. In particular, comparison of the plasmids from environmental and clinical strains shows that the genes for resistance to heavy metals were eliminated in the latter, with the simultaneous accumulation of antibiotic resistance genes by incorporation of transposons and integrons carrying these genes. The results demonstrate that this group of mega-plasmids plays a key role in the dissemination of multi-drug resistance among Acinetobacter species.
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Affiliation(s)
- Sofia Mindlin
- Institute of Molecular Genetics of National Research Center "Kurchatov Institute", Moscow, Russia
| | - Olga Maslova
- Institute of Molecular Genetics of National Research Center "Kurchatov Institute", Moscow, Russia
| | - Alexey Beletsky
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Varvara Nurmukanova
- Institute of Molecular Genetics of National Research Center "Kurchatov Institute", Moscow, Russia
| | - Zhiyong Zong
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Andrey Mardanov
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Mayya Petrova
- Institute of Molecular Genetics of National Research Center "Kurchatov Institute", Moscow, Russia
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17
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Castanheira M, Simner PJ, Bradford PA. Extended-spectrum β-lactamases: an update on their characteristics, epidemiology and detection. JAC Antimicrob Resist 2021; 3:dlab092. [PMID: 34286272 PMCID: PMC8284625 DOI: 10.1093/jacamr/dlab092] [Citation(s) in RCA: 262] [Impact Index Per Article: 87.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Extended-spectrum β-lactamase (ESBL)-producing Gram-negative pathogens are a major cause of resistance to expanded-spectrum β-lactam antibiotics. Since their discovery in the early 1980s, they have spread worldwide and an are now endemic in Enterobacterales isolated from both hospital-associated and community-acquired infections. As a result, they are a global public health concern. In the past, TEM- and SHV-type ESBLs were the predominant families of ESBLs. Today CTX-M-type enzymes are the most commonly found ESBL type with the CTX-M-15 variant dominating worldwide, followed in prevalence by CTX-M-14, and CTX-M-27 is emerging in certain parts of the world. The genes encoding ESBLs are often found on plasmids and harboured within transposons or insertion sequences, which has enabled their spread. In addition, the population of ESBL-producing Escherichia coli is dominated globally by a highly virulent and successful clone belonging to ST131. Today, there are many diagnostic tools available to the clinical microbiology laboratory and include both phenotypic and genotypic tests to detect β-lactamases. Unfortunately, when ESBLs are not identified in a timely manner, appropriate antimicrobial therapy is frequently delayed, resulting in poor clinical outcomes. Several analyses of clinical trials have shown mixed results with regards to whether a carbapenem must be used to treat serious infections caused by ESBLs or whether some of the older β-lactam-β-lactamase combinations such as piperacillin/tazobactam are appropriate. Some of the newer combinations such as ceftazidime/avibactam have demonstrated efficacy in patients. ESBL-producing Gram-negative pathogens will continue to be major contributor to antimicrobial resistance worldwide. It is essential that we remain vigilant about identifying them both in patient isolates and through surveillance studies.
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He T, Li R, Wei R, Liu D, Bai L, Zhang L, Gu J, Wang R, Wang Y. Characterization of Acinetobacter indicus co-harbouring tet(X3) and blaNDM-1 of dairy cow origin. J Antimicrob Chemother 2021; 75:2693-2696. [PMID: 32449918 DOI: 10.1093/jac/dkaa182] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Tao He
- Key Laboratory for Control Technology and Standard for Agro-product Safety and Quality, Ministry of Agriculture and Rural Affairs, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Ruichao Li
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Ruicheng Wei
- Key Laboratory for Control Technology and Standard for Agro-product Safety and Quality, Ministry of Agriculture and Rural Affairs, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Dejun Liu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Li Bai
- Food Safety Research Unit of Chinese Academy of Medical Sciences, China National Center for Food Safety Risk Assessment, Beijing, China
| | - Lili Zhang
- Key Laboratory for Control Technology and Standard for Agro-product Safety and Quality, Ministry of Agriculture and Rural Affairs, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Jili Gu
- Key Laboratory for Control Technology and Standard for Agro-product Safety and Quality, Ministry of Agriculture and Rural Affairs, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Ran Wang
- Key Laboratory for Control Technology and Standard for Agro-product Safety and Quality, Ministry of Agriculture and Rural Affairs, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Yang Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
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19
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Gheorghe I, Barbu IC, Surleac M, Sârbu I, Popa LI, Paraschiv S, Feng Y, Lazăr V, Chifiriuc MC, Oţelea D, Zhiyong Z. Subtypes, resistance and virulence platforms in extended-drug resistant Acinetobacter baumannii Romanian isolates. Sci Rep 2021; 11:13288. [PMID: 34168184 PMCID: PMC8225882 DOI: 10.1038/s41598-021-92590-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 06/09/2021] [Indexed: 02/05/2023] Open
Abstract
Acinetobacter baumannii has emerged worldwide as a dominant pathogen in a broad range of severe infections, raising an acute need for efficient antibacterials. This is the first report on the resistome and virulome of 33 extended drug-resistant and carbapenem-resistant A. baumannii (XDR CRAB) strains isolated from hospitalized and ambulatory patients in Bucharest, Romania. A total of 33 isolates were collected and analyzed using phenotypic antibiotic susceptibility and conjugation assays, PCR, whole-genome sequencing (WGS), pulsed-field gel electrophoresis (PFGE) and MultiLocus Sequence Typing (MLST). All isolates were extensively drug-resistant (XDR), being susceptible only to colistin. The carbapenem resistance was attributed by PCR mainly to blaOXA-24 and blaOXA-23 genes. PFGE followed by MLST analysis demonstrated the presence of nine pulsotypes and six sequence types. WGS of seven XDR CRAB isolates from healthcare-associated infections demonstrated the high diversity of resistance genes repertoire, as well as of mobile genetic elements, carrying ARGs for aminoglycosides, sulphonamides and macrolides. Our data will facilitate the understanding of resistance, virulence and transmission features of XDR AB isolates from Romanian patients and might be able to contribute to the implementation of appropriate infection control measures and to develop new molecules with innovative mechanisms of action, able to fight effectively against these bugs, for limiting the spread and decreasing the infection rate and mortality.
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Affiliation(s)
- Irina Gheorghe
- grid.5100.40000 0001 2322 497XDepartment of Microbiology and Immunology, Faculty of Biology, University of Bucharest, Bucharest, Romania ,grid.5100.40000 0001 2322 497XResearch Institute of the University of Bucharest (ICUB), Bucharest, Romania
| | - Ilda Czobor Barbu
- grid.5100.40000 0001 2322 497XDepartment of Microbiology and Immunology, Faculty of Biology, University of Bucharest, Bucharest, Romania ,grid.5100.40000 0001 2322 497XResearch Institute of the University of Bucharest (ICUB), Bucharest, Romania
| | - Marius Surleac
- grid.5100.40000 0001 2322 497XResearch Institute of the University of Bucharest (ICUB), Bucharest, Romania ,grid.8194.40000 0000 9828 7548National Institute for Infectious Diseases “Matei Bals”, Bucharest, Romania
| | - Ionela Sârbu
- grid.5100.40000 0001 2322 497XResearch Institute of the University of Bucharest (ICUB), Bucharest, Romania ,grid.5100.40000 0001 2322 497XGenetics Department, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Laura Ioana Popa
- grid.5100.40000 0001 2322 497XDepartment of Microbiology and Immunology, Faculty of Biology, University of Bucharest, Bucharest, Romania ,grid.5100.40000 0001 2322 497XResearch Institute of the University of Bucharest (ICUB), Bucharest, Romania ,grid.435400.60000 0004 0369 4845Department of Bioinformatics, National Institute of Research and Development for Biological Sciences, Bucharest, Romania
| | - Simona Paraschiv
- grid.8194.40000 0000 9828 7548National Institute for Infectious Diseases “Matei Bals”, Bucharest, Romania
| | - Yu Feng
- grid.13291.380000 0001 0807 1581Centre of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Veronica Lazăr
- grid.5100.40000 0001 2322 497XDepartment of Microbiology and Immunology, Faculty of Biology, University of Bucharest, Bucharest, Romania ,grid.5100.40000 0001 2322 497XResearch Institute of the University of Bucharest (ICUB), Bucharest, Romania
| | - Mariana Carmen Chifiriuc
- grid.5100.40000 0001 2322 497XDepartment of Microbiology and Immunology, Faculty of Biology, University of Bucharest, Bucharest, Romania ,grid.5100.40000 0001 2322 497XResearch Institute of the University of Bucharest (ICUB), Bucharest, Romania ,grid.435118.aAcademy of Romanian Scientists, 050045 Bucharest, Romania
| | - Dan Oţelea
- grid.8194.40000 0000 9828 7548National Institute for Infectious Diseases “Matei Bals”, Bucharest, Romania
| | - Zong Zhiyong
- grid.13291.380000 0001 0807 1581Centre of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
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20
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Jia J, Guan Y, Li X, Fan X, Zhu Z, Xing H, Wang Z. Phenotype profiles and adaptive preference of Acinetobacter johnsonii isolated from Ba River with different environmental backgrounds. ENVIRONMENTAL RESEARCH 2021; 196:110913. [PMID: 33639142 DOI: 10.1016/j.envres.2021.110913] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/02/2021] [Accepted: 02/17/2021] [Indexed: 06/12/2023]
Abstract
Acinetobacter johnsonii is a potentially opportunistic pathogen widely distributed in nosocomial and natural environments, but little attention has been paid to this bacillus. Here A. johnsonii strains from Ba River with different pollution levels were isolated. In this study, we found that the increasing anthropogenic contaminants accounted for the emergence of multidrug-resistant (MDR) A. johnsonii strains. Correlation analysis results showed that the resistance phenotype of strains could be generated by co-selection of heavy metals or non-corresponding antibiotics. The whole genome sequence analysis showed that the relative heavy pollution of water selects strains containing more survival-relevant genes. We found that only some genes like blaOXA-24 were responsible for its corresponding resistance profile. Additionally, the tolerance profiles toward heavy metals also attribute to the expression of efflux pumps rather than corresponding resistance genes. In summary, our finding revealed that the resistance profiles of A. johnsonii could be generated by cross or co-selection of anthropogenic contaminants and mediated by efflux pumps instead of corresponding resistance determinants. Our study also has deep-sight into the adaptive preference of bacteria in natural environments, and contributes to surveillance studies and MDR- A. johnsonii monitoring worldwide.
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Affiliation(s)
- Jia Jia
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yongjing Guan
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xiangju Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xiaoteng Fan
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Zeliang Zhu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Haoran Xing
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Zaizhao Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China.
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21
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Alattraqchi AG, Mohd Rani F, A Rahman NI, Ismail S, Cleary DW, Clarke SC, Yeo CC. Complete Genome Sequencing of Acinetobacter baumannii AC1633 and Acinetobacter nosocomialis AC1530 Unveils a Large Multidrug-Resistant Plasmid Encoding the NDM-1 and OXA-58 Carbapenemases. mSphere 2021; 6:e01076-20. [PMID: 33504662 PMCID: PMC7885321 DOI: 10.1128/msphere.01076-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 01/08/2021] [Indexed: 11/20/2022] Open
Abstract
Carbapenem-resistant Acinetobacter spp. are considered priority drug-resistant human-pathogenic bacteria. The genomes of two carbapenem-resistant Acinetobacter spp. clinical isolates obtained from the same tertiary hospital in Terengganu, Malaysia, namely, A. baumannii AC1633 and A. nosocomialis AC1530, were sequenced. Both isolates were found to harbor the carbapenemase genes blaNDM-1 and blaOXA-58 in a large (ca. 170 kb) plasmid designated pAC1633-1 and pAC1530, respectively, that also encodes genes that confer resistance to aminoglycosides, sulfonamides, and macrolides. The two plasmids were almost identical except for the insertion of ISAba11 and an IS4 family element in pAC1633-1, and ISAba11 along with relBE toxin-antitoxin genes flanked by inversely orientated pdif (XerC/XerD) recombination sites in pAC1530. The blaNDM-1 gene was encoded in a Tn125 composite transposon structure flanked by ISAba125, whereas blaOXA-58 was flanked by ISAba11 and ISAba3 downstream and a partial ISAba3 element upstream within a pdif module. The presence of conjugative genes in plasmids pAC1633-1/pAC1530 and their discovery in two distinct species of Acinetobacter from the same hospital are suggestive of conjugative transfer, but mating experiments failed to demonstrate transmissibility under standard laboratory conditions. Comparative sequence analysis strongly inferred that pAC1633-1/pAC1530 was derived from two separate plasmids in an IS1006-mediated recombination or transposition event. A. baumannii AC1633 also harbored three other plasmids designated pAC1633-2, pAC1633-3, and pAC1633-4. Both pAC1633-3 and pAC1633-4 are cryptic plasmids, whereas pAC1633-2 is a 12,651-bp plasmid of the GR8/GR23 Rep3-superfamily group that encodes the tetA(39) tetracycline resistance determinant in a pdif module.IMPORTANCE Bacteria of the genus Acinetobacter are important hospital-acquired pathogens, with carbapenem-resistant A. baumannii listed by the World Health Organization as the one of the top priority pathogens. Whole-genome sequencing of carbapenem-resistant A. baumannii AC1633 and A. nosocomialis AC1530, which were isolated from the main tertiary hospital in Terengganu, Malaysia, led to the discovery of a large, ca. 170-kb plasmid that harbored genes encoding the New Delhi metallo-β-lactamase-1 (NDM-1) and OXA-58 carbapenemases alongside genes that conferred resistance to aminoglycosides, macrolides, and sulfonamides. The plasmid was a patchwork of multiple mobile genetic elements and comparative sequence analysis indicated that it may have been derived from two separate plasmids through an IS1006-mediated recombination or transposition event. The presence of such a potentially transmissible plasmid encoding resistance to multiple antimicrobials warrants vigilance, as its spread to susceptible strains would lead to increasing incidences of antimicrobial resistance.
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Affiliation(s)
- Ahmed Ghazi Alattraqchi
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Terengganu, Malaysia
| | - Farahiyah Mohd Rani
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Terengganu, Malaysia
| | - Nor Iza A Rahman
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Terengganu, Malaysia
| | - Salwani Ismail
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Terengganu, Malaysia
| | - David W Cleary
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Trust, Southampton, United Kingdom
| | - Stuart C Clarke
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Trust, Southampton, United Kingdom
- Global Health Research Institute, University of Southampton, Southampton, United Kingdom
- School of Postgraduate Studies, International Medical University, Kuala Lumpur, Malaysia
- Centre for Translational Research, IMU Institute for Research, Development and Innovation (IRDI), Kuala Lumpur, Malaysia
| | - Chew Chieng Yeo
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Terengganu, Malaysia
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22
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Colistin Dependence in Extensively Drug-Resistant Acinetobacter baumannii Strain Is Associated with IS Ajo2 and IS Aba13 Insertions and Multiple Cellular Responses. Int J Mol Sci 2021; 22:ijms22020576. [PMID: 33430070 PMCID: PMC7827689 DOI: 10.3390/ijms22020576] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 01/05/2021] [Accepted: 01/06/2021] [Indexed: 02/06/2023] Open
Abstract
The nosocomial opportunistic Gram-negative bacterial pathogen Acinetobacter baumannii is resistant to multiple antimicrobial agents and an emerging global health problem. The polymyxin antibiotic colistin, targeting the negatively charged lipid A component of the lipopolysaccharide on the bacterial cell surface, is often considered as the last-resort treatment, but resistance to colistin is unfortunately increasing worldwide. Notably, colistin-susceptible A. baumannii can also develop a colistin dependence after exposure to this drug in vitro. Colistin dependence might represent a stepping stone to resistance also in vivo. However, the mechanisms are far from clear. To address this issue, we combined proteogenomics, high-resolution microscopy, and lipid profiling to characterize and compare A. baumannii colistin-susceptible clinical isolate (Ab-S) of to its colistin-dependent subpopulation (Ab-D) obtained after subsequent passages in moderate colistin concentrations. Incidentally, in the colistin-dependent subpopulation the lpxA gene was disrupted by insertion of ISAjo2, the lipid A biosynthesis terminated, and Ab-D cells displayed a lipooligosaccharide (LOS)-deficient phenotype. Moreover, both mlaD and pldA genes were perturbed by insertions of ISAjo2 and ISAba13, and LOS-deficient bacteria displayed a capsule with decreased thickness as well as other surface imperfections. The major changes in relative protein abundance levels were detected in type 6 secretion system (T6SS) components, the resistance-nodulation-division (RND)-type efflux pumps, and in proteins involved in maintenance of outer membrane asymmetry. These findings suggest that colistin dependence in A. baumannii involves an ensemble of mechanisms seen in resistance development and accompanied by complex cellular events related to insertional sequences (ISs)-triggered LOS-deficiency. To our knowledge, this is the first study demonstrating the involvement of ISAjo2 and ISAba13 IS elements in the modulation of the lipid A biosynthesis and associated development of dependence on colistin.
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23
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Ayibieke A, Kobayashi A, Suzuki M, Sato W, Mahazu S, Prah I, Mizoguchi M, Moriya K, Hayashi T, Suzuki T, Iwanaga S, Ablordey A, Saito R. Prevalence and Characterization of Carbapenem-Hydrolyzing Class D β-Lactamase-Producing Acinetobacter Isolates From Ghana. Front Microbiol 2020; 11:587398. [PMID: 33281784 PMCID: PMC7691484 DOI: 10.3389/fmicb.2020.587398] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Accepted: 10/15/2020] [Indexed: 12/14/2022] Open
Abstract
Multidrug resistance, especially carbapenem resistance in Acinetobacter bacteria is a global healthcare concern. However, available data on the phenotypic and genotypic characteristics of Acinetobacter isolates from West Africa, including Ghana is scanty. Our aim was to investigate the antibiotic resistance profile and genotypic characteristics of Acinetobacter isolates from Ghana and to characterize carbapenemase producers using whole-genome sequencing (WGS). A total of 36 Acinetobacter isolates collected at three hospitals in Ghana between 2016 and 2017 were analyzed. MICs were determined by commercial antibiotic plates. Acinetobacter baumannii MLST was determined using the Pasteur scheme. WGS of OXA-carbapenemase producers was performed using short- and long-read sequencing strategies. The resistance rate was highest for trimethoprim/sulfamethoxazole (n = 22; 61%). Six (16.7%) and eight (22.2%) isolates were resistant to ceftazidime and colistin, respectively. Two (5.6%) isolates were resistant and one (2.8%) isolate had intermediate sensitivity to three carbapenems. Fifteen STs were identified in 24 A. baumannii isolates including six new STs (ST1467 ∼ ST1472). ST78 was the predominant (n = 6) followed by ST1469 (n = 3). Four carbapenemase-producing A. baumannii isolates also were identified. Isogenic ST103 isolates Ab-B004d-c and Ab-D10a-a harbored blaOXA–23 within Tn2007 on identical plasmids, pAb-B004d-c_3, and pAb-D10a-a_3. ST1472 isolate Ab-C102 and ST107 isolate Ab-C63 carried blaOXA–58 and blaOXA–420, a rare blaOXA–58 variant, respectively, within novel genetic contexts. Our results show that A. baumannii isolates of diverse and unique genotypes, including OXA-carbapenemase producers, are circulating in Ghana highlighting the need for a wider surveillance of antimicrobial resistance.
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Affiliation(s)
- Alafate Ayibieke
- Department of Molecular Microbiology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ayumi Kobayashi
- Department of Molecular Microbiology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Masato Suzuki
- Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Wakana Sato
- Department of Molecular Microbiology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Samiratu Mahazu
- Department of Molecular Microbiology, Tokyo Medical and Dental University, Tokyo, Japan.,Department of Environmental Parasitology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Isaac Prah
- Department of Molecular Microbiology, Tokyo Medical and Dental University, Tokyo, Japan.,Department of Molecular Virology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Miyuki Mizoguchi
- Department of Infection Control and Prevention, The University of Tokyo Hospital, Tokyo, Japan
| | - Kyoji Moriya
- Department of Infection Control and Prevention, The University of Tokyo Hospital, Tokyo, Japan
| | - Takaya Hayashi
- Department of Molecular Virology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Toshihiko Suzuki
- Department of Bacterial Pathogenesis, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shiroh Iwanaga
- Department of Environmental Parasitology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Anthony Ablordey
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Ryoichi Saito
- Department of Molecular Microbiology, Tokyo Medical and Dental University, Tokyo, Japan
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24
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Mindlin S, Beletsky A, Rakitin A, Mardanov A, Petrova M. Acinetobacter Plasmids: Diversity and Development of Classification Strategies. Front Microbiol 2020; 11:588410. [PMID: 33304332 PMCID: PMC7693717 DOI: 10.3389/fmicb.2020.588410] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 10/23/2020] [Indexed: 11/13/2022] Open
Abstract
Bacteria of the genus Acinetobacter, with their numerous species common in various habitats, play a significant role as pathogens. Their ability to adapt to different living conditions is largely due to the presence of numerous plasmids containing the necessary adaptive genes. At the same time the diversity of Acinetobacter plasmids and their evolutionary dynamics have not been sufficiently studied. Here, we characterized 44 plasmids isolated from five permafrost Acinetobacter lwoffii strains, examined their relationship with plasmids of modern Acinetobacter strains and identified groups of related plasmids. For this purpose, we have developed a combined approach for classifying all known Acinetobacter plasmids. The classification took into account the size of plasmids, the presence and structure of the rep and mob genes, as well as the structure of their backbone and accessory regions. Based on the analysis, 19 major groups (lineages) of plasmids were identified, of which more than half were small plasmids. The plasmids of each group have common features of the organization of the backbone region with a DNA identity level of at least 80%. In addition, plasmids of the same group have similarities in the organization of accessory regions. We also described a number of plasmids with a unique structure. The presence of plasmids in clinical strains that are closely related to those of environmental permafrost strains provides evidence of the origin of the former from the latter.
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Affiliation(s)
- Sofia Mindlin
- Institute of Molecular Genetics of National Research Centre "Kurchatov Institute", Moscow, Russia
| | - Alexey Beletsky
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Andrey Rakitin
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Andrey Mardanov
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Mayya Petrova
- Institute of Molecular Genetics of National Research Centre "Kurchatov Institute", Moscow, Russia
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25
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Zong G, Zhong C, Fu J, Zhang Y, Zhang P, Zhang W, Xu Y, Cao G, Zhang R. The carbapenem resistance gene bla OXA-23 is disseminated by a conjugative plasmid containing the novel transposon Tn6681 in Acinetobacter johnsonii M19. Antimicrob Resist Infect Control 2020; 9:182. [PMID: 33168102 PMCID: PMC7653874 DOI: 10.1186/s13756-020-00832-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 10/16/2020] [Indexed: 12/18/2022] Open
Abstract
Background Carbapenem resistant Acinetobacter species have caused great difficulties in clinical therapy in the worldwide. Here we describe an Acinetobacter johnsonii M19 with a novel blaOXA-23 containing transposon Tn6681 on the conjugative plasmid pFM-M19 and the ability to transferand carbapenem resistance.
Methods A. johnsonii M19 was isolated under selection with 8 mg/L meropenem from hospital sewage, and the minimum inhibitory concentrations (MICs) for the representative carbapenems imipenem, meropenem and ertapenem were determined. The genome of A. johnsonii M19 was sequenced by PacBio RS II and Illumina HiSeq 4000 platforms. A homologous model of OXA-23 was generated, and molecular docking models with imipenem, meropenem and ertapenem were constructed by Discovery Studio 2.0. Type IV secretion system and conjugation elements were identified by the Pathosystems Resource Integration Center (PATRIC) server and the oriTfinder. Mating experiments were performed to evaluate transfer of OXA-23 to Escherichia coli 25DN. Results MICs of A. johnsonii M19 for imipenem, meropenem and ertapenem were 128 mg/L, 48 mg/L and 24 mg/L, respectively. Genome sequencing identified plasmid pFM-M19, which harbours the carbapenem resistance gene blaOXA-23 within the novel transposon Tn6681. Molecular docking analysis indicated that the elongated hydrophobic tunnel of OXA-23 provides a hydrophobic environment and that Lys-216, Thr-217, Met-221 and Arg-259 were the conserved amino acids bound to imipenem, meropenem and ertapenem. Furthermore, pFM-M19 could transfer blaOXA-23 to E. coli 25DN by conjugation, resulting in carbapenem-resistant transconjugants.
Conclusions Our investigation showed that A. johnsonii M19 is a source and disseminator of blaOXA-23 and carbapenem resistance. The ability to transfer blaOXA-23 to other species by the conjugative plasmid pFM-M19 raises the risk of spread of carbapenem resistance. Graphic abstract The carbapenem resistance gene blaOXA-23 is disseminated by a conjugative plasmid containing the novel transposon Tn6681 in Acinetobacter johnsonii M19.![]()
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Affiliation(s)
- Gongli Zong
- Key Laboratory of Industrial Biotechnology of Ministry of Education and School of Biotechnology, Jiangnan University, Wuxi, 214122, China.,Department of Epidemiology, The First Affiliated Hospital of Shandong First Medical University, Jinan, 250062, China.,Shandong Medicinal Biotechnology Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, 250062, China
| | - Chuanqing Zhong
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China
| | - Jiafang Fu
- Department of Epidemiology, The First Affiliated Hospital of Shandong First Medical University, Jinan, 250062, China.,Shandong Medicinal Biotechnology Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, 250062, China.,Key Lab for Biotech-Drugs of National Health Commission, Jinan, 250062, China
| | - Yu Zhang
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China
| | - Peipei Zhang
- Department of Epidemiology, The First Affiliated Hospital of Shandong First Medical University, Jinan, 250062, China.,Shandong Medicinal Biotechnology Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, 250062, China.,Key Lab for Biotech-Drugs of National Health Commission, Jinan, 250062, China
| | - Wenchi Zhang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Yan Xu
- Key Laboratory of Industrial Biotechnology of Ministry of Education and School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Guangxiang Cao
- Department of Epidemiology, The First Affiliated Hospital of Shandong First Medical University, Jinan, 250062, China. .,Shandong Medicinal Biotechnology Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, 250062, China.
| | - Rongzhen Zhang
- Key Laboratory of Industrial Biotechnology of Ministry of Education and School of Biotechnology, Jiangnan University, Wuxi, 214122, China.
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26
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Wang J, Wang Y, Wu H, Wang ZY, Shen PC, Tian YQ, Sun F, Pan ZM, Jiao X. Coexistence of bla OXA-58 and tet(X) on a Novel Plasmid in Acinetobacter sp. From Pig in Shanghai, China. Front Microbiol 2020; 11:578020. [PMID: 33042094 PMCID: PMC7530245 DOI: 10.3389/fmicb.2020.578020] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 08/18/2020] [Indexed: 12/31/2022] Open
Abstract
The purpose of this study was to characterize the complete sequence of a novel plasmid carrying tigecycline resistance gene tet(X) and carbapenemase gene blaOXA-58 from a swine Acinetobacter sp. strain SH19PTT10. Minimal inhibitory concentration (MIC) was performed using microbroth dilution method. The isolate SH19PTT10 was highly resistant (16 mg/L) to tigecycline, and also exhibited resistance to ampicillin, streptomycin, tetracycline, chloramphenicol, florfenicol, ciprofloxacin, and sulfamethoxazole/trimethoprim. Although SH19PTT10 harbored blaOXA-58, it was susceptible to cefotaxime and meropenem. The genome sequence of SH19PTT10 was determined using PacBio single-molecule real-time sequencing. Plasmid pYUSHP10-1 had a size of 174,032 bp and showed partial homology to several plasmids found in Acinetobacter isolates. It contained two repA genes, putative toxin-antitoxin systems (HipA/HipB, RelE/RelB, and BrnT/BrnA), partitioning genes (parA and parB), and heavy metal resistance-associated genes (copA/copB, nrp, and czcA/czcD) but the transfer region or proteins was not found. pYUSHP10-1 carried 16 resistance genes, mainly clustered in two mosaic multiresistance regions (MRRs). The first MRR contained sul3, qacI-aadA1-clmA1-aadA2-blaCARB-2-dfrA16 cassette, aac(3)-IId, and blaOXA-58. The blaOXA-58 gene was associated with ISAba3, as previously described. The second MRR is the tet(X) region (ISAcsp12-aph(3')-Ia-IS26-ΔxerD-tet(X)-res-ISCR2-sul2) related to the corresponding region in other tet(X)-bearing plasmids. The pdif sites, as well as mobile elements, play an important role in mobilization of DNA modules and plasmid evolution. Coexistence of numerous resistance genes on a single plasmid may contribute to the dissemination of these genes under pressure posed by different agents, which may explain the presence of clinically crucial resistance genes tet(X) and blaOXA-58 in livestock. Thus, rational drug use and continued surveillance of tet(X) and blaOXA-58 in livestock are warranted.
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Affiliation(s)
- Jing Wang
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, China.,Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Yan Wang
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, China.,Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Han Wu
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, China.,Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Zhen-Yu Wang
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, China.,Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Peng-Cheng Shen
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, China.,Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Yu-Qi Tian
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, China.,Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Fan Sun
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, China.,Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Zhi-Ming Pan
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, China.,Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
| | - Xinan Jiao
- Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou, China.,Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
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27
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Brovedan MA, Cameranesi MM, Limansky AS, Morán-Barrio J, Marchiaro P, Repizo GD. What do we know about plasmids carried by members of the Acinetobacter genus? World J Microbiol Biotechnol 2020; 36:109. [PMID: 32656745 DOI: 10.1007/s11274-020-02890-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 07/04/2020] [Indexed: 02/07/2023]
Abstract
Several Acinetobacter spp. act as opportunistic pathogens causing healthcare-associated infections worldwide, and in this respect their ability to resist antimicrobial compounds has certainly boosted up their global propagation. Acinetobacter clinical strains have demonstrated a remarkable ability to evolve and become resistant to almost all available drugs in the antimicrobial arsenal, including the last-resort carbapenem β-lactams. The dissemination of antimicrobial resistant genes (ARG), heavy metals-detoxification systems and other traits such as virulence factors is facilitated by mobile genetic elements (MGE) through horizontal gene transfer. Among them, plasmids have been shown to play a critical role in this genus. Despite the continuous increase of Acinetobacter plasmid sequences present in databases, there are no reports describing the basic traits carried by these MGE. To fill this gap, a broad analysis of the Acinetobacter plasmidome was performed. A search for Acinetobacter complete plasmids indicated that 905 sequences have been deposited in the NCBI-GenBank public database, of which 492 are harbored by Acinetobacter baumannii strains. Plasmid-classification schemes based on Rep proteins homology have so far described 23 different groups for A. baumannii (GR1-23), and 16 Acinetobacter Rep3 Groups (AR3G1-16) for the complete genus. Acinetobacter plasmids size ranges from 1.3 to 400 kb. Interestingly, widespread plasmids which are < 20 kb make up 56% of the total present in members of this genus. This led to the proposal of Acinetobacter plasmid assignation to two groups according to their size (< 20 kb and > 20 kb). Usually, smaller plasmids are not self-transmissible, and thereby employ alternative mechanisms of dissemination. For instance, a subgroup of < 20 kb-plasmids belonging to the pRAY-family, lack a rep gene, but encode a relaxase enabling their mobilization by conjugative plasmids. Other subgroup, including small GR2 Acinetobacter plasmids, does not encode a relaxase gene. However, they could still be mobilized by conjugative plasmids which recognize an oriT region carried by these small plasmids. Also, these < 20 kb-plasmids usually carry accessory genes bordered by XerC/D-recombinases recognition sites which have been hypothesized to mediate plasmid plasticity. Conversely, many cases of larger plasmids are self-transmissible and might encode virulence factors and their regulators, thus controlling strain pathogenicity. The ARGs carried by the > 20 kb-plasmids are usually encoded within other MGEs such as transposons, or as part of integrons. It has been recently noted that some of the > 20 kb-plasmids are derived from excised phages, and thus dubbed as phage-like plasmids. All in all, the plethora of plasmids found in strains of this genus and the multiple strategies promoting their evolution and dissemination have certainly contributed to survival of the Acinetobacter members in different habitats, including the clinical environment.
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Affiliation(s)
- Marco A Brovedan
- Instituto de Biología Molecular y Celular de Rosario (IBR, CONICET), Laboratorio de Resistencia a Antimicrobianos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - María M Cameranesi
- Instituto de Biología Molecular y Celular de Rosario (IBR, CONICET), Laboratorio de Resistencia a Antimicrobianos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Adriana S Limansky
- Instituto de Biología Molecular y Celular de Rosario (IBR, CONICET), Laboratorio de Resistencia a Antimicrobianos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Jorgelina Morán-Barrio
- Instituto de Biología Molecular y Celular de Rosario (IBR, CONICET), Laboratorio de Resistencia a Antimicrobianos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Patricia Marchiaro
- Instituto de Biología Molecular y Celular de Rosario (IBR, CONICET), Laboratorio de Resistencia a Antimicrobianos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Guillermo D Repizo
- Instituto de Biología Molecular y Celular de Rosario (IBR, CONICET), Laboratorio de Resistencia a Antimicrobianos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
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Phylogeographical Analyses and Antibiotic Resistance Genes of Acinetobacter johnsonii Highlight Its Clinical Relevance. mSphere 2020; 5:5/4/e00581-20. [PMID: 32611704 PMCID: PMC7333577 DOI: 10.1128/msphere.00581-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Acinetobacter johnsonii has been severely understudied and its population structure and the presence of antibiotic resistance genes (ARGs) are very much uncertain. Our phylogeographical analysis shows that intercontinental transmission has occurred frequently and that different lineages are circulating within single countries; notably, clinical and nonclinical strains are not well differentiated from one another. Importantly, in this species recombination is a significant source of single nucleotide polymorphisms. Acinetobacter johnsonii has been severely understudied and its population structure and the presence of antibiotic resistance genes (ARGs) are very much uncertain. Our phylogeographical analysis shows that intercontinental transmission has occurred frequently and that different lineages are circulating within single countries; notably, clinical and nonclinical strains are not well differentiated from one another. Importantly, in this species recombination is a significant source of single nucleotide polymorphisms. Furthermore, our results show this species could be an important reservoir of ARGs since it has a significant amount of ARGs, and many of them show signals of horizontal gene transfer. Thus, this study clearly points out the clinical importance of A. johnsonii and the urgent need to better appreciate its genomic diversity.
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Tang L, Shen W, Zhang Z, Zhang J, Wang G, Xiang L, She J, Hu X, Zou G, Zhu B, Zhou Y. Whole-Genome Analysis of Two Copies of bla NDM-1 Gene Carrying Acinetobacter johnsonii Strain Acsw19 Isolated from Sichuan, China. Infect Drug Resist 2020; 13:855-865. [PMID: 32273730 PMCID: PMC7106997 DOI: 10.2147/idr.s236200] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 03/03/2020] [Indexed: 12/14/2022] Open
Abstract
Purpose To characterize the genetic feature of the carbapenems resistant Acinetobacter johnsonii strain Acsw19 isolated from municipal sludge. This strain was found to carry two copies of bla NDM-1, cmlB1-like gene, and bla OXA-211-like gene along with other 8 antimicrobial resistance genes, 3 plasmids, 15 genomic islands and 8 prophages. Methods A carbapenem-resistant Acinetobacter johnsonii strain Acsw19 isolated from municipal sludge was subjected to whole-genome sequencing (WGS) via the PacBio and Illumina MiSeq platforms. Thereafter, the characteristic was analyzed by a series of bioinformatics software. Results The results showed that the genome of Acsw19 was consisted of a 3,433,749 bp circular chromosome and 3 circular plasmids, pAcsw19-1 (11,161 bp), pAcsw19-2 (351,885 bp) and pAcsw19-3 (38,391bp), respectively. Resistome analysis showed that Acsw19 carried 12 antimicrobial resistance genes, including 6 [cmlB1-like, bla NDM-1, bla OXA-58, aph (3')-VIa, msr(E) and mph(E)] in the plasmid pAcsw19-2 and 6 (bla OXA-211-like, bla NDM-1, aph(3")-Ib, aph(6)-Id, sul2, and floR) in the chromosome genome. Specifically, the cmlB1-like gene shared 86.33%, 71.7% and 71.9% similarities with the cmlB1, cmlA4 and cmlA8 gene, and the bla OXA-211-like gene shared 94.4%, 95.39% and 96.36% similarities with bla OXA-211, bla OXA-643 and bla OXA-652, at the nucleotide level, respectively. Phylogenetic analysis showed that the bla OXA-211-like gene and cmlB1-like gene had the closest evolutionary relationship with bla OXA-643 and cmlB1, respectively. These results indicated that the bla OXA-211-like and cmlB1-like genes identified in the current study should be the novel variant resistance genes. Conclusion Carrying of two copies of bla NDM-1, cmlB1-like, bla OXA-211-like and along with other 8 antimicrobial resistance genes, 3 plasmids, 15 genomic islands and 8 prophages Acinetobacter johnsonii strain might increase the possibility of spreading of resistance genes.
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Affiliation(s)
- Lingtong Tang
- Department of Clinical Laboratory, The People's Hospital of Gao County, Sichuan 644000, People's Republic of China.,Department of Pathogenic Biology, School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - Wei Shen
- Department of Pathogenic Biology, School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, People's Republic of China.,Department of Clinical Laboratory, The First People's Hospital of Yibin, Yibin 644000, Sichuan, People's Republic of China
| | - Zhikun Zhang
- Department of Pathogenic Biology, School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - Jingping Zhang
- Department of Pathogenic Biology, School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - Guangxi Wang
- Department of Pathogenic Biology, School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - Li Xiang
- Department of Pathogenic Biology, School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - Junping She
- Department of Pathogenic Biology, School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - Xiaoyan Hu
- Department of Pathogenic Biology, School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, People's Republic of China
| | - Guoyuan Zou
- Institute of Plant Nutrition and Resources, Beijing Academy of Agriculture and Forestry Science, Beijing, People's Republic of China
| | - Baoli Zhu
- Key Laboratory of Pathogenic Microbiology & Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Yingshun Zhou
- Department of Pathogenic Biology, School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, People's Republic of China
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Brovedan M, Repizo GD, Marchiaro P, Viale AM, Limansky A. Characterization of the diverse plasmid pool harbored by the blaNDM-1-containing Acinetobacter bereziniae HPC229 clinical strain. PLoS One 2019; 14:e0220584. [PMID: 31743332 PMCID: PMC6863613 DOI: 10.1371/journal.pone.0220584] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 10/24/2019] [Indexed: 11/18/2022] Open
Abstract
Acinetobacter bereziniae is an environmental microorganism with increasing clinical incidence, and may thus provide a model for a bacterial species bridging the gap between the environment and the clinical setting. A. bereziniae plasmids have been poorly studied, and their characterization could offer clues on the causes underlying the leap between these two different habitats. Here we characterized the whole plasmid content of A. bereziniae HPC229, a clinical strain previously reported to harbor a 44-kbp plasmid, pNDM229, conferring carbapenem and aminoglycoside resistance. We identified five extra plasmids in HPC229 ranging from 114 to 1.3 kbp, including pAbe229-114 (114 kbp) encoding a MOBP111 relaxase and carrying heavy metal resistance, a bacteriophage defense BREX system and four different toxin-antitoxin (TA) systems. Two other replicons, pAbe229-15 (15.4 kbp) and pAbe229-9 (9.1 kbp), both encoding MOBQ1 relaxases and also carrying TA systems, were found. The three latter plasmids contained Acinetobacter Rep_3 superfamily replication initiator protein genes, and functional analysis of their transfer regions revealed the mobilizable nature of them. HPC229 also harbors two smaller plasmids, pAbe229-4 (4.4 kbp) and pAbe229-1 (1.3 kbp), the former bearing a ColE1-type replicon and a TA system, and the latter lacking known replication functions. Comparative sequence analyses against deposited Acinetobacter genomes indicated that the above five HPC229 plasmids were unique, although some regions were also present in other of these genomes. The transfer, replication, and adaptive modules in pAbe229-15, and the stability module in pAbe229-9, were bordered by sites potentially recognized by XerC/XerD site-specific tyrosine recombinases, thus suggesting a potential mechanism for their acquisition. The presence of Rep_3 and ColE1-based replication modules, different mob genes, distinct adaptive functions including resistance to heavy metal and other environmental stressors, as well as antimicrobial resistance genes, and a high content of XerC/XerD sites among HPC229 plasmids provide evidence of substantial links with bacterial species derived from both environmental and clinical habitats.
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Affiliation(s)
- Marco Brovedan
- Instituto de Biología Molecular y Celular de Rosario (IBR), Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, CONICET, Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Guillermo D. Repizo
- Instituto de Biología Molecular y Celular de Rosario (IBR), Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, CONICET, Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Patricia Marchiaro
- Instituto de Biología Molecular y Celular de Rosario (IBR), Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, CONICET, Universidad Nacional de Rosario (UNR), Rosario, Argentina
| | - Alejandro M. Viale
- Instituto de Biología Molecular y Celular de Rosario (IBR), Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, CONICET, Universidad Nacional de Rosario (UNR), Rosario, Argentina
- * E-mail: (AMV); (AL)
| | - Adriana Limansky
- Instituto de Biología Molecular y Celular de Rosario (IBR), Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, CONICET, Universidad Nacional de Rosario (UNR), Rosario, Argentina
- * E-mail: (AMV); (AL)
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Mindlin S, Beletsky A, Mardanov A, Petrova M. Adaptive dif Modules in Permafrost Strains of Acinetobacter lwoffii and Their Distribution and Abundance Among Present Day Acinetobacter Strains. Front Microbiol 2019; 10:632. [PMID: 30984151 PMCID: PMC6449649 DOI: 10.3389/fmicb.2019.00632] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 03/13/2019] [Indexed: 12/22/2022] Open
Abstract
The dif/Xer system of site-specific recombination allows resolution of chromosomal dimers during bacterial DNA replication. Recently, it was also shown to be involved in horizontal transfer of a few known Xer-dependent mobile elements. Here, we show that plasmids of various Acinetobacter species, including clinically important strains, often contain multiple pdif sites that are mainly located within their accessory regions. Chromosomes of Acinetobacter strains may also contain additional dif sites, and their similarity with plasmid pdif sites is higher than with the main chromosomal site dif1. We further identify putative mobile genetic elements containing pdif sites on both flanks of adaptive genes and analyze their distribution in Acinetobacter species. In total, we describe seven mobile elements containing genes with various adaptive functions from permafrost strains of A. lwoffii group. All of them are also spread in modern plasmids of different Acinetobacter species including A. baumannii. We could not detect pdif sites and corresponding mobile elements in closely related bacterial genera, including Psychrobacter and Moraxella. Thus, the widespread distribution of dif modules is a characteristic feature of Acinetobacter species and may contribute to their high adaptability both in the environment and in the clinic.
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Affiliation(s)
- Sofia Mindlin
- Laboratory of Molecular Genetics of Microorganisms, Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, Russia
| | - Alexey Beletsky
- Laboratory of Microorganism Genomics and Metagenomics, Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Andrey Mardanov
- Laboratory of Microorganism Genomics and Metagenomics, Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Mayya Petrova
- Laboratory of Molecular Genetics of Microorganisms, Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, Russia
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MITE Aba12 , a Novel Mobile Miniature Inverted-Repeat Transposable Element Identified in Acinetobacter baumannii ATCC 17978 and Its Prevalence across the Moraxellaceae Family. mSphere 2019; 4:4/1/e00028-19. [PMID: 30787115 PMCID: PMC6382973 DOI: 10.1128/mspheredirect.00028-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
One of the most important weapons in the armory of Acinetobacter is its impressive genetic plasticity, facilitating rapid genetic mutations and rearrangements as well as integration of foreign determinants carried by mobile genetic elements. Of these, IS are considered one of the key forces shaping bacterial genomes and ultimately evolution. We report the identification of a novel nonautonomous IS-derived element present in multiple bacterial species from the Moraxellaceae family and its recent translocation into the hns locus in the A. baumannii ATCC 17978 genome. The latter finding adds new knowledge to only a limited number of documented examples of MITEs in the literature and underscores the plastic nature of the hns locus in A. baumannii. MITEAba12, and its predicted parent(s), may be a source of substantial adaptive evolution within environmental and clinically relevant bacterial pathogens and, thus, have broad implications for niche-specific adaptation. Insertion sequences (IS) are fundamental mediators of genome plasticity with the potential to generate phenotypic variation with significant evolutionary outcomes. Here, a recently active miniature inverted-repeat transposon element (MITE) was identified in a derivative of Acinetobacter baumannii ATCC 17978 after being subjected to stress conditions. Transposition of the novel element led to the disruption of the hns gene, resulting in a characteristic hypermotile phenotype. DNA identity shared between the terminal inverted repeats of this MITE and coresident ISAba12 elements, together with the generation of 9-bp target site duplications, provides strong evidence that ISAba12 elements were responsible for mobilization of the MITE (designated MITEAba12) within this strain. A wider genome-level survey identified MITEAba12 in 30 additional Acinetobacter genomes at various frequencies and one Moraxella osloensis genome. Ninety MITEAba12 copies could be identified, of which 40% had target site duplications, indicating recent transposition events. Elements ranged between 111 and 114 bp; 90% were 113 bp in length. Using the MITEAba12 consensus sequence, putative outward-facing Escherichia coli σ70 promoter sequences in both orientations were identified. The identification of transcripts originating from the promoter in one direction supports the proposal that the element can influence neighboring host gene transcription. The location of MITEAba12 varied significantly between and within genomes, preferentially integrating into AT-rich regions. Additionally, a copy of MITEAba12 was identified in a novel 8.5-kb composite transposon, Tn6645, in the M. osloensis CCUG 350 chromosome. Overall, this study shows that MITEAba12 is the most abundant nonautonomous element currently found in Acinetobacter. IMPORTANCE One of the most important weapons in the armory of Acinetobacter is its impressive genetic plasticity, facilitating rapid genetic mutations and rearrangements as well as integration of foreign determinants carried by mobile genetic elements. Of these, IS are considered one of the key forces shaping bacterial genomes and ultimately evolution. We report the identification of a novel nonautonomous IS-derived element present in multiple bacterial species from the Moraxellaceae family and its recent translocation into the hns locus in the A. baumannii ATCC 17978 genome. The latter finding adds new knowledge to only a limited number of documented examples of MITEs in the literature and underscores the plastic nature of the hns locus in A. baumannii. MITEAba12, and its predicted parent(s), may be a source of substantial adaptive evolution within environmental and clinically relevant bacterial pathogens and, thus, have broad implications for niche-specific adaptation.
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NDM Metallo-β-Lactamases and Their Bacterial Producers in Health Care Settings. Clin Microbiol Rev 2019; 32:32/2/e00115-18. [PMID: 30700432 DOI: 10.1128/cmr.00115-18] [Citation(s) in RCA: 385] [Impact Index Per Article: 77.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
New Delhi metallo-β-lactamase (NDM) is a metallo-β-lactamase able to hydrolyze almost all β-lactams. Twenty-four NDM variants have been identified in >60 species of 11 bacterial families, and several variants have enhanced carbapenemase activity. Klebsiella pneumoniae and Escherichia coli are the predominant carriers of bla NDM, with certain sequence types (STs) (for K. pneumoniae, ST11, ST14, ST15, or ST147; for E. coli, ST167, ST410, or ST617) being the most prevalent. NDM-positive strains have been identified worldwide, with the highest prevalence in the Indian subcontinent, the Middle East, and the Balkans. Most bla NDM-carrying plasmids belong to limited replicon types (IncX3, IncFII, or IncC). Commonly used phenotypic tests cannot specifically identify NDM. Lateral flow immunoassays specifically detect NDM, and molecular approaches remain the reference methods for detecting bla NDM Polymyxins combined with other agents remain the mainstream options of antimicrobial treatment. Compounds able to inhibit NDM have been found, but none have been approved for clinical use. Outbreaks caused by NDM-positive strains have been reported worldwide, attributable to sources such as contaminated devices. Evidence-based guidelines on prevention and control of carbapenem-resistant Gram-negative bacteria are available, although none are specific for NDM-positive strains. NDM will remain a severe challenge in health care settings, and more studies on appropriate countermeasures are required.
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Hadjadj L, Bakour S, Rolain JM. Co-occurrence of carbapenemase encoding genes in Acinetobacter baumannii, a dream or reality? BMC Microbiol 2018; 18:107. [PMID: 30185164 PMCID: PMC6125877 DOI: 10.1186/s12866-018-1252-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 08/28/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Acinetobacter baumannii is an important opportunistic pathogen that is rapidly evolving towards multidrug resistance and is responsible for life-threatening infections. Carbapenems are commonly used to treat A. baumannii infections but the emergence of carbapenemase encoding genes, such as blaOXA-23-like, blaOXA-24-like, blaOXA-58-like, and blaNDM has been reported. Moreover, several studies have reported the co-occurrence of two distinct carbapenemases in some isolates. The aim of the present study is to demonstrate whether the phenomenon of co-occurrence of two distinct carbapenemase encoding genes in a single isolate still exists. RESULTS We studied six strains of A. baumannii including one harboring blaOXA-23-like and blaOXA-24-like genes and five with blaOXA-23-like and blaNDM genes. One colony of each strain was inoculated in sterile water and diluted ten-fold. Each dilution was cultivated on trypticase soy agar plates for 24 h at 37 °C and the isolated bacteria were analyzed. For two of the six tested strains, we identified two different populations of A. baumannii, each with a different carbapenemase, genes encoding aminoglycoside modifying enzymes, resistance phenotype, and clonal type. In addition, the two different populations had the same aspect on the agar plate. CONCLUSIONS Here, we demonstrate that A. baumannii infections could be linked to multiple clones harboring different carbapenemase encoding genes in the same sample. In addition, we describe an easy method of verifying the presence of co-occurrence of carbapenemase in one isolate.
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Affiliation(s)
- Linda Hadjadj
- Aix Marseille Univ, IRD, APHM, MEPHI, IHU Méditerranée Infection, Faculté de Médecine et de Pharmacie, 19-21 boulevard Jean Moulin, 13385 Marseille CEDEX 05, France
| | - Sofiane Bakour
- Aix Marseille Univ, IRD, APHM, MEPHI, IHU Méditerranée Infection, Faculté de Médecine et de Pharmacie, 19-21 boulevard Jean Moulin, 13385 Marseille CEDEX 05, France
| | - Jean-Marc Rolain
- Aix Marseille Univ, IRD, APHM, MEPHI, IHU Méditerranée Infection, Faculté de Médecine et de Pharmacie, 19-21 boulevard Jean Moulin, 13385 Marseille CEDEX 05, France
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Complete Sequence of the IncA/C 1 Plasmid pCf587 Carrying blaPER-2 from Citrobacter freundii. Antimicrob Agents Chemother 2018; 62:AAC.00006-18. [PMID: 29463531 DOI: 10.1128/aac.00006-18] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 02/13/2018] [Indexed: 12/29/2022] Open
Abstract
The blaPER-2-harboring plasmid pCf587 (191,541 bp) belongs to lineage IncA/C1 and is closely related to pRA1. It contains a large resistance island including the blaPER-2 gene between two copies of ISKox2-like elements, the toxin-antitoxin module pemK-pemI, several other resistance genes inserted within a Tn2 transposon, a Tn21-like structure, and a class 1 integron. pCf587 belongs to sequence type 13 (ST13), a new plasmid multilocus sequence typing (pMLST) ST.
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Whole-Genome Analysis of an Extensively Drug-Resistance Empedobacter falsenii Strain Reveals Distinct Features and the Presence of a Novel Metallo-ß-Lactamase (EBR-2). Curr Microbiol 2018; 75:1084-1089. [DOI: 10.1007/s00284-018-1498-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 04/19/2018] [Indexed: 11/26/2022]
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Yan DZ, Gan YT, Zhou H, Liu J, Li X. Draft Genome Sequence of Cyclohexylamine-Degrading Strain Acinetobacter sp. YT-02 Isolated. Curr Microbiol 2017; 75:284-287. [PMID: 29063968 DOI: 10.1007/s00284-017-1377-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Accepted: 10/19/2017] [Indexed: 11/28/2022]
Abstract
Acinetobacter sp. YT-02, a Gram-negative bacterium isolated from the activated sludge from a sodium N-cyclohexylsulfamate production plant, has the ability to degrade cyclohexylamine. It was classified as a member of Acinetobacter sp., a Gram-negative bacterium, sharing a 16S rRNA gene sequence identity of 99% with Acinetobacter guangdongensis strain 1NM-4. It could degrade 10 mmol/L cyclohexylamine within 22 h. Based on the identified metabolite, the metabolic pathway of cyclohexylamine could be postulated as it was degraded via cyclohexanone. Draft genome sequence of this strain (2,993, 647 bp of chromosome length) is presented here. We further identified the genes encoding the enzymes involved in cyclohexylamine oxidation to cyclohexanone and the subsequent downstream metabolic pathway of cyclohexanone oxidation. Strain YT-02 has the potentiality to be applied in the treatment of the pollutant cyclohexylamine, and it could also be treated as a research material to study the degradation mechanism of cyclohexylamine.
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Affiliation(s)
- Da-Zhong Yan
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, No.68 Xuefu South Road, Changqing Garden, Wuhan, 430023, Hubei Province, China.
| | - Ya-Ting Gan
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, No.68 Xuefu South Road, Changqing Garden, Wuhan, 430023, Hubei Province, China
| | - Hui Zhou
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, No.68 Xuefu South Road, Changqing Garden, Wuhan, 430023, Hubei Province, China
| | - Jun Liu
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, No.68 Xuefu South Road, Changqing Garden, Wuhan, 430023, Hubei Province, China
| | - Xin Li
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, No.68 Xuefu South Road, Changqing Garden, Wuhan, 430023, Hubei Province, China
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The tet39 Determinant and the msrE-mphE Genes in Acinetobacter Plasmids Are Each Part of Discrete Modules Flanked by Inversely Oriented p dif (XerC-XerD) Sites. Antimicrob Agents Chemother 2017; 61:AAC.00780-17. [PMID: 28533235 DOI: 10.1128/aac.00780-17] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 05/15/2017] [Indexed: 01/29/2023] Open
Abstract
The tet39 tetracycline resistance determinant and the macrolide resistance genes msrE and mphE were found in an 18.2-kb plasmid, pS30-1, recovered from a global clone 2 (GC2) Acinetobacter baumannii isolate from Singapore, that conferred resistance to tetracycline and erythromycin. pS30-1 also contains mobA and mobC genes encoding MOBQ family proteins, but attempts to mobilize pS30-1 utilizing a coresident conjugative repAci6 plasmid were unsuccessful. Eight pdif sites, consisting of inversely oriented binding sites for the XerC and XerD recombinases separated by 6 bp, were detected in pS30-1. The tet39 determinant and the msrE-mphE gene pair are each surrounded by two pdif sites in inverse orientation. Identical regions in different contexts and many previously unnoticed pdif sites were found in a number of different plasmids in GenBank, showing that the tet39 and msrE-mphE dif modules are mobile. A putative toxin/antitoxin system, a gene encoding a serine recombinase, and open reading frames of unknown function were also part of dif modules in pS30-1. In general, modules with internal XerC or XerD sites alternate. Two copies of ISAjo2-1 (94% identical to ISAjo2) in pS30-1 were inserted 5 bp from a XerC site, and this appears to be the preferred insertion site for this insertion sequence (IS) group. Apparently, Acinetobacter plasmids exploit the Acinetobacter XerC-XerD recombinases to mobilize DNA units containing resistance and other genes, via an uncharacterized mechanism. The tet39 and msrE-mphE dif modules add to the oxa24 module and the oxa58 module redefined here, bringing the total of resistance gene-containing dif modules in Acinetobacter plasmids to four.
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Draft Genome Sequence of Acinetobacter johnsonii C6, an Environmental Isolate Engaging in Interspecific Metabolic Interactions. GENOME ANNOUNCEMENTS 2017; 5:5/16/e00155-17. [PMID: 28428290 PMCID: PMC5399249 DOI: 10.1128/genomea.00155-17] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Acinetobacter johnsonii C6 originates from creosote-polluted groundwater and performs ecological and evolutionary interactions with Pseudomonas putida in biofilms. The draft genome of A. johnsonii C6 is 3.7 Mbp and was shaped by mobile genetic elements. It reveals genes facilitating the biodegradation of aromatic hydrocarbons and resistance to antimicrobials and metals.
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Zhang G, Leclercq SO, Tian J, Wang C, Yahara K, Ai G, Liu S, Feng J. A new subclass of intrinsic aminoglycoside nucleotidyltransferases, ANT(3")-II, is horizontally transferred among Acinetobacter spp. by homologous recombination. PLoS Genet 2017; 13:e1006602. [PMID: 28152054 PMCID: PMC5313234 DOI: 10.1371/journal.pgen.1006602] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 02/16/2017] [Accepted: 01/24/2017] [Indexed: 12/16/2022] Open
Abstract
The emergence and spread of antibiotic resistance among Acinetobacter spp. have been investigated extensively. Most studies focused on the multiple antibiotic resistance genes located on plasmids or genomic resistance islands. On the other hand, the mechanisms controlling intrinsic resistance are still not well understood. In this study, we identified the novel subclass of aminoglycoside nucleotidyltransferase ANT(3")-II in Acinetobacter spp., which comprised numerous variants distributed among three main clades. All members of this subclass can inactivate streptomycin and spectinomycin. The three ant(3")-II genes, encoding for the three ANT(3")-II clades, are widely distributed in the genus Acinetobacter and always located in the same conserved genomic region. According to their prevalence, these genes are intrinsic in Acinetobacter baumannii, Acinetobacter pittii, and Acinetobacter gyllenbergii. We also demonstrated that the ant(3")-II genes are located in a homologous recombination hotspot and were recurrently transferred among Acinetobacter species. In conclusion, our findings demonstrated a novel mechanism of natural resistance in Acinetobacter spp., identified a novel subclass of aminoglycoside nucleotidyltransferase and provided new insight into the evolutionary history of intrinsic resistance genes. The level of interest in intrinsic resistance genes has increased recently, and one of reasons is that their mobilization could lead to emergence of resistant pathogens. Insertion sequences (ISs) or plasmids can capture intrinsic resistance genes and disseminate them in bacterial populations. In this study, we identified a novel subclass of aminoglycoside nucleotidyltransferases which are intrinsic in A. baumannii and other Acinetobacter species. The genes encoding the aminoglycoside nucleotidyltransferase were frequently horizontally transferred between different Acinetobacter species by homologous recombination. This work reports a novel mechanism of natural resistance in Acinetobacter and an overlooked pathway for the dissemination of resistance among species in this genus.
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Affiliation(s)
- Gang Zhang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Sébastien Olivier Leclercq
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Jingjing Tian
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Chao Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Koji Yahara
- Department of Bacteriology II, National Institute of Infectious Diseases, Musashimurayama, Tokyo, Japan
| | - Guomin Ai
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Shuangjiang Liu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Jie Feng
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- * E-mail:
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Chromosomal Amplification of the blaOXA-58 Carbapenemase Gene in a Proteus mirabilis Clinical Isolate. Antimicrob Agents Chemother 2017; 61:AAC.01697-16. [PMID: 27855079 DOI: 10.1128/aac.01697-16] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 10/24/2016] [Indexed: 01/30/2023] Open
Abstract
Horizontal gene transfer may occur between distantly related bacteria, thus leading to genetic plasticity and in some cases to acquisition of novel resistance traits. Proteus mirabilis is an enterobacterial species responsible for human infections that may express various acquired β-lactam resistance genes, including different classes of carbapenemase genes. Here we report a Proteus mirabilis clinical isolate (strain 1091) displaying resistance to penicillin, including temocillin, together with reduced susceptibility to carbapenems and susceptibility to expanded-spectrum cephalosporins. Using biochemical tests, significant carbapenem hydrolysis was detected in P. mirabilis 1091. Since PCR failed to detect acquired carbapenemase genes commonly found in Enterobacteriaceae, we used a whole-genome sequencing approach that revealed the presence of blaOXA-58 class D carbapenemase gene, so far identified only in Acinetobacter species. This gene was located on a 3.1-kb element coharboring a blaAmpC-like gene. Remarkably, these two genes were bracketed by putative XerC-XerD binding sites and inserted at a XerC-XerD site located between the terminase-like small- and large-subunit genes of a bacteriophage. Increased expression of the two bla genes resulted from a 6-time tandem amplification of the element as revealed by Southern blotting. This is the first isolation of a clinical P. mirabilis strain producing OXA-58, a class D carbapenemase, and the first description of a XerC-XerD-dependent insertion of antibiotic resistance genes within a bacteriophage. This study revealed a new role for the XerC-XerD recombinase in bacteriophage biology.
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Jamsheer A, Rafay AM, Daoud Z, Morrissey I, Torumkuney D. Results from the Survey of Antibiotic Resistance (SOAR) 2011-13 in the Gulf States. J Antimicrob Chemother 2016; 71 Suppl 1:i45-61. [PMID: 27048582 DOI: 10.1093/jac/dkw064] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES To provide surveillance data on the susceptibility of community-acquired respiratory tract isolates from four Gulf and Near East countries from 2011 to 2013. METHODS MICs were determined using Etests(®) for all antibiotics evaluated except erythromycin, where testing was by disc diffusion. Susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. RESULTS Seven hundred and twenty-six respiratory isolates comprising 265 isolates of Streptococcus pneumoniae, 125 isolates of Streptococcus pyogenes and 336 isolates of Haemophilus influenzae were collected from Bahrain, Lebanon, Oman and the United Arab Emirates (UAE). Among S. pneumoniae, susceptibility to penicillin was low in the UAE and Bahrain. Macrolide susceptibility was ∼45%-60% in the UAE and Oman but higher in Lebanon (73.7%) and Bahrain (84%-85%). Penicillin susceptibility using CLSI intravenous breakpoints was >85% in all countries. Antibiotic susceptibility of S. pneumoniae was lower in UAE and Oman. Among S. pyogenes isolates, resistance to erythromycin was highest in Oman (31.6%) but <20% in the other countries. In H. influenzae, susceptibility to most antibiotics was high, except for ampicillin in Lebanon (70.2%) and amoxicillin in Oman (95.4%). Lebanon also had a high percentage (14.9%) of β-lactamase-positive isolates with non-susceptibility to ampicillin. Amoxicillin/clavulanic acid susceptibility was >95% in all countries. Use of EUCAST versus CLSI breakpoints demonstrated profound differences for cefaclor and cefuroxime in S. pneumoniae and H. influenzae, with EUCAST showing lower susceptibility. CONCLUSIONS There was considerable variability in susceptibility among countries in the same region. Thus, continued surveillance is necessary to track future changes in antibiotic resistance.
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Affiliation(s)
- A Jamsheer
- Salmaniya Medical Complex, P.O. Box 12, Manama, Bahrain
| | - A M Rafay
- Sultan Qaboos University Hospital, P.O. Box 38, Post code 123, Muscat, Oman
| | - Z Daoud
- University of Balamand, Faculty of Medicine and Medical Sciences, Clinical Microbiology, Department of Biomedical Sciences, P.O. Box 100, Tripoli, Lebanon
| | - I Morrissey
- IHMA Europe Sàrl, 9A route de la Corniche, Epalinges 1066, Switzerland
| | - D Torumkuney
- GlaxoSmithKline, 980 Great West Road, Brentford, Middlesex TW8 9GS, UK
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Torumkuney D, Chaiwarith R, Reechaipichitkul W, Malatham K, Chareonphaibul V, Rodrigues C, Chitins DS, Dias M, Anandan S, Kanakapura S, Park YJ, Lee K, Lee H, Kim JY, Lee Y, Lee HK, Kim JH, Tan TY, Heng YX, Mukherjee P, Morrissey I. Results from the Survey of Antibiotic Resistance (SOAR) 2012-14 in Thailand, India, South Korea and Singapore. J Antimicrob Chemother 2016; 71 Suppl 1:i3-19. [PMID: 27048580 DOI: 10.1093/jac/dkw073] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES To provide susceptibility data for community-acquired respiratory tract isolates of Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenzae and Moraxella catarrhalis collected in 2012-14 from four Asian countries. METHODS MICs were determined using Etest(®) for all antibiotics except erythromycin, which was evaluated by disc diffusion. Susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. For macrolide/clindamycin interpretation, breakpoints were adjusted for incubation in CO2 where available. RESULTS Susceptibility of S. pneumoniae was generally lower in South Korea than in other countries. Penicillin susceptibility assessed using CLSI oral or EUCAST breakpoints ranged from 21.2% in South Korea to 63.8% in Singapore. In contrast, susceptibility using CLSI intravenous breakpoints was much higher, at 79% in South Korea and ∼95% or higher elsewhere. Macrolide susceptibility was ∼20% in South Korea and ∼50%-60% elsewhere. Among S. pyogenes isolates (India only), erythromycin susceptibility (∼20%) was lowest of the antibiotics tested. In H. influenzae antibiotic susceptibility was high except for ampicillin, where susceptibility ranged from 16.7% in South Korea to 91.1% in India. South Korea also had a high percentage (18.1%) of β-lactamase-negative ampicillin-resistant isolates. Amoxicillin/clavulanic acid susceptibility for each pathogen (PK/PD high dose) was between 93% and 100% in all countries except for H. influenzae in South Korea (62.5%). CONCLUSIONS Use of EUCAST versus CLSI breakpoints had profound differences for cefaclor, cefuroxime and ofloxacin, with EUCAST showing lower susceptibility. There was considerable variability in susceptibility among countries in the same region. Thus, continued surveillance is necessary to track future changes in antibiotic resistance.
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Affiliation(s)
- D Torumkuney
- GlaxoSmithKline, 980 Great West Road, Brentford, Middlesex TW8 9GS, UK
| | - R Chaiwarith
- Faculty of Medicine, Chiang Mai University, Maharaj Nakorn Chiang Mai Hospital, 110 Intavaroros Road, Tambon Sribhoom, Muang, Chiang Mai 50200, Thailand
| | - W Reechaipichitkul
- Khon Kaen University Faculty of Medicine, Srinagarind Hospital, 123 Mittraphap Highway, Tambol Naimuang, Muang District, Khon Kaen 40002, Thailand
| | - K Malatham
- Mahidol University Faculty of Medicine Ramathibodi Hospital, 270 Rama VI. Road, oong Phayathai, Ratchathewi, Bangkok 10400, Thailand
| | - V Chareonphaibul
- GlaxoSmithKline Thailand, 12th Floor, Wave Place, 55 Wireless Road, Lumpini, Patumwan, Bangkok 10330, Thailand
| | - C Rodrigues
- Hinduja Hospital and Medical Research Centre, Department of Microbiology, Veer Savarkar Marg, Mahim, Mumbai 400 016, India
| | - D S Chitins
- Choithram Hospital and Research Centre, Department of Microbiology, Manik Bagh Road, Indore 452 014 (M/P), India
| | - M Dias
- St John's Medical College Hospital, Department of Microbiology, Sarjapur Road, Bangalore 560 034, India
| | - S Anandan
- Christian Medical College, Department of Microbiology, Vellore 632 004, India
| | - S Kanakapura
- GlaxoSmithKline India, No. 5 Embassy Links, Cunningham (SRT) Road, Bangalore 560 052, India
| | - Y J Park
- The Catholic University of Korea, Seoul St Mary's Hospital, 222 Banpo-daero, Seocho-Gu, Seoul, South Korea
| | - K Lee
- Yonsei University College of Medicine, Severance Hospital, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, South Korea
| | - H Lee
- Yonsei University College of Medicine, Gangnam Severance Hospital, 211 Eonju-ro, Gangnam-gu, Seoul, South Korea
| | - J Y Kim
- Yonsei University College of Medicine, Gangnam Severance Hospital, 211 Eonju-ro, Gangnam-gu, Seoul, South Korea
| | - Y Lee
- Hanyang University Medical Center, 222-1, Wangsimni-ro, Seongdong-gu, Seoul, South Korea
| | - H K Lee
- The Catholic University of Korea, Uijongbu St Mary's Hospital, 271, Cheonbo-ro, Ukjeongbu-si, Gyeonggi-do, Korea
| | - J H Kim
- GlaxoSmithKline Korea, LS Yongsan Tower, 9th Floor, Hangang 191, Yongsan-gu, Seoul, South Korea
| | - T Y Tan
- Changi General Hospital Pte Ltd (Reg. No. 198904226R), 2 Simei Street 3, Singapore 529889
| | - Y X Heng
- Changi General Hospital Pte Ltd (Reg. No. 198904226R), 2 Simei Street 3, Singapore 529889
| | - P Mukherjee
- GlaxoSmithKline Singapore, (Reg. No. 198102938K), 150 Beach Road, No. 22-00 Gateway West, Singapore 189720
| | - I Morrissey
- IHMA Europe Sàrl, 9A Route de la Corniche, Epalinges 1066, Switzerland
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Insights on the Horizontal Gene Transfer of Carbapenemase Determinants in the Opportunistic Pathogen Acinetobacter baumannii. Microorganisms 2016; 4:microorganisms4030029. [PMID: 27681923 PMCID: PMC5039589 DOI: 10.3390/microorganisms4030029] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 07/21/2016] [Accepted: 08/09/2016] [Indexed: 12/23/2022] Open
Abstract
Horizontal gene transfer (HGT) is a driving force to the evolution of bacteria. The fast emergence of antimicrobial resistance reflects the ability of genetic adaptation of pathogens. Acinetobacter baumannii has emerged in the last few decades as an important opportunistic nosocomial pathogen, in part due to its high capacity of acquiring resistance to diverse antibiotic families, including to the so-called last line drugs such as carbapenems. The rampant selective pressure and genetic exchange of resistance genes hinder the effective treatment of resistant infections. A. baumannii uses all the resistance mechanisms to survive against carbapenems but production of carbapenemases are the major mechanism, which may act in synergy with others. A. baumannii appears to use all the mechanisms of gene dissemination. Beyond conjugation, the mostly reported recent studies point to natural transformation, transduction and outer membrane vesicles-mediated transfer as mechanisms that may play a role in carbapenemase determinants spread. Understanding the genetic mobilization of carbapenemase genes is paramount in preventing their dissemination. Here we review the carbapenemases found in A. baumannii and present an overview of the current knowledge of contributions of the various HGT mechanisms to the molecular epidemiology of carbapenem resistance in this relevant opportunistic pathogen.
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Montaña S, Schramm STJ, Traglia GM, Chiem K, Parmeciano Di Noto G, Almuzara M, Barberis C, Vay C, Quiroga C, Tolmasky ME, Iriarte A, Ramírez MS. The Genetic Analysis of an Acinetobacter johnsonii Clinical Strain Evidenced the Presence of Horizontal Genetic Transfer. PLoS One 2016; 11:e0161528. [PMID: 27548264 PMCID: PMC4993456 DOI: 10.1371/journal.pone.0161528] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 08/08/2016] [Indexed: 02/08/2023] Open
Abstract
Acinetobacter johnsonii rarely causes human infections. While most A. johnsonii isolates are susceptible to virtually all antibiotics, strains harboring a variety of β-lactamases have recently been described. An A. johnsonii Aj2199 clinical strain recovered from a hospital in Buenos Aires produces PER-2 and OXA-58. We decided to delve into its genome by obtaining the whole genome sequence of the Aj2199 strain. Genome comparison studies on Aj2199 revealed 240 unique genes and a close relation to strain WJ10621, isolated from the urine of a patient in China. Genomic analysis showed evidence of horizontal genetic transfer (HGT) events. Forty-five insertion sequences and two intact prophages were found in addition to several resistance determinants such as blaPER-2, blaOXA-58, blaTEM-1, strA, strB, ereA, sul1, aacC2 and a new variant of blaOXA-211, called blaOXA-498. In particular, blaPER-2 and blaTEM-1 are present within the typical contexts previously described in the Enterobacteriaceae family. These results suggest that A. johnsonii actively acquires exogenous DNA from other bacterial species and concomitantly becomes a reservoir of resistance genes.
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Affiliation(s)
- Sabrina Montaña
- Instituto de Investigaciones en Microbiología y Parasitología Médica (IMPaM, UBA-CONICET), Buenos Aires, Argentina
| | - Sareda T. J. Schramm
- Department of Biological Science, California State University Fullerton, Fullerton, CA, United States of America
| | - German Matías Traglia
- Instituto de Investigaciones en Microbiología y Parasitología Médica (IMPaM, UBA-CONICET), Buenos Aires, Argentina
| | - Kevin Chiem
- Instituto de Investigaciones en Microbiología y Parasitología Médica (IMPaM, UBA-CONICET), Buenos Aires, Argentina
- Department of Biological Science, California State University Fullerton, Fullerton, CA, United States of America
| | - Gisela Parmeciano Di Noto
- Instituto de Investigaciones en Microbiología y Parasitología Médica (IMPaM, UBA-CONICET), Buenos Aires, Argentina
| | - Marisa Almuzara
- Laboratorio de Bacteriología Clínica, Departamento de Bioquímica Clínica, Hospital de Clínicas José de San Martín, Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - Claudia Barberis
- Laboratorio de Bacteriología Clínica, Departamento de Bioquímica Clínica, Hospital de Clínicas José de San Martín, Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - Carlos Vay
- Laboratorio de Bacteriología Clínica, Departamento de Bioquímica Clínica, Hospital de Clínicas José de San Martín, Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - Cecilia Quiroga
- Instituto de Investigaciones en Microbiología y Parasitología Médica (IMPaM, UBA-CONICET), Buenos Aires, Argentina
| | - Marcelo E. Tolmasky
- Department of Biological Science, California State University Fullerton, Fullerton, CA, United States of America
| | - Andrés Iriarte
- Departamento de Desarrollo Biotecnológico, Instituto de Higiene, Facultad de Medicina, UdelaR, Montevideo, Uruguay
| | - María Soledad Ramírez
- Instituto de Investigaciones en Microbiología y Parasitología Médica (IMPaM, UBA-CONICET), Buenos Aires, Argentina
- Department of Biological Science, California State University Fullerton, Fullerton, CA, United States of America
- * E-mail:
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Exploring non-hospital-related settings in Angola reveals new Acinetobacter reservoirs for blaOXA-23 and blaOXA-58. Int J Antimicrob Agents 2016; 48:228-30. [DOI: 10.1016/j.ijantimicag.2016.06.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 06/08/2016] [Accepted: 06/11/2016] [Indexed: 11/17/2022]
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Comparative genomic analysis of novel Acinetobacter symbionts: A combined systems biology and genomics approach. Sci Rep 2016; 6:29043. [PMID: 27378055 PMCID: PMC4932630 DOI: 10.1038/srep29043] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 06/08/2016] [Indexed: 12/20/2022] Open
Abstract
The increasing trend of antibiotic resistance in Acinetobacter drastically limits the range of therapeutic agents required to treat multidrug resistant (MDR) infections. This study focused on analysis of novel Acinetobacter strains using a genomics and systems biology approach. Here we used a network theory method for pathogenic and non-pathogenic Acinetobacter spp. to identify the key regulatory proteins (hubs) in each strain. We identified nine key regulatory proteins, guaA, guaB, rpsB, rpsI, rpsL, rpsE, rpsC, rplM and trmD, which have functional roles as hubs in a hierarchical scale-free fractal protein-protein interaction network. Two key hubs (guaA and guaB) were important for insect-associated strains, and comparative analysis identified guaA as more important than guaB due to its role in effective module regulation. rpsI played a significant role in all the novel strains, while rplM was unique to sheep-associated strains. rpsM, rpsB and rpsI were involved in the regulation of overall network topology across all Acinetobacter strains analyzed in this study. Future analysis will investigate whether these hubs are useful as drug targets for treating Acinetobacter infections.
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