scholarly journals The plasmid diversity of Acinetobacter bereziniae HPC229 provides clues on the ability of the species to thrive on both clinical and environmental habitats

2019 ◽  
Author(s):  
Marco Brovedan ◽  
Guillermo D. Repizo ◽  
Patricia Marchiaro ◽  
Alejandro M. Viale ◽  
Adriana Limansky

AbstractAcinetobacter 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 radically 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. 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.


2019 ◽  
Vol 9 (1) ◽  
pp. 16-23
Author(s):  
Maryam Lami Riskuwa-Shehu ◽  
Haruna Yahaya Ismail ◽  
Udem Joshua Josiah Ijah

Heavy metal resistant bacteria are widespread in nature and their application in decontamination of polluted ecosystems is promising. In this study, ability of endophytic bacteria isolated from Psidium guajava (Guava) and Mangifera indica (Mango) for heavy metal resistance was assessed. Leaves samples form the two plants were collected and processed according to the standard laboratory practices. Heavy metals were analyzed using Atomic absorption spectrophotometer. Endophytic bacteria were isolated and identified using morphological and biochemical characteristics; heavy metal resistance was determined by plate dilution method. Heavy metal analysis revealed that the leaves samples contained considerable quantities of Manganese (Mn), Lead (Pb) and Cadmium (Cd) ranging from 1.21±1.6 mg/Kg (for Cd in Guava leaves) to 116.58±1.3 mg/Kg (for Mn in Mango leaves). A total of six bacterial species were isolated from both of the plants leaves (3 each). Guava endophytes were identified as Streptococcus sp, Staphylococcus albus and Staphylococcus seiuri whereas Staphylococcus aureus, Staphylococcus xylulose and Staphylococcus intermedius were from Mango leaves. The identified isolates were tested for ability to resist heavy metals in-vitro and were capable of showing different patterns of resistance to MnCl2, PbCl2 and CdCl2.  All the endophytes were highly resistant to PbCl2 followed by MnCl2 but susceptible to CdCl2. The ability of plants and bacterial endophytes understudy to tolerate or resist heavy metals is a good indication of their phytoremediation potentials and thus, should be harnessed.



2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Stefan E. Heiden ◽  
Nils-Olaf Hübner ◽  
Jürgen A. Bohnert ◽  
Claus-Dieter Heidecke ◽  
Axel Kramer ◽  
...  

Abstract Background Antibiotic-resistant Klebsiella pneumoniae are a major cause of hospital- and community-acquired infections, including sepsis, liver abscess, and pneumonia, driven mainly by the emergence of successful high-risk clonal lineages. The K. pneumoniae sequence type (ST) 307 lineage has appeared in several different parts of the world after first being described in Europe in 2008. From June to October 2019, we recorded an outbreak of an extensively drug-resistant ST307 lineage in four medical facilities in north-eastern Germany. Methods Here, we investigated these isolates and those from subsequent cases in the same facilities. We performed whole-genome sequencing to study phylogenetics, microevolution, and plasmid transmission, as well as phenotypic experiments including growth curves, hypermucoviscosity, siderophore secretion, biofilm formation, desiccation resilience, serum survival, and heavy metal resistance for an in-depth characterization of this outbreak clone. Results Phylogenetics suggest a homogenous phylogram with several sub-clades containing either isolates from only one patient or isolates originating from different patients, suggesting inter-patient transmission. We identified three large resistance plasmids, carrying either NDM-1, CTX-M-15, or OXA-48, which K. pneumoniae ST307 likely donated to other K. pneumoniae isolates of different STs and even other bacterial species (e.g., Enterobacter cloacae) within the clinical settings. Several chromosomally and plasmid-encoded, hypervirulence-associated virulence factors (e.g., yersiniabactin, metabolite transporter, aerobactin, and heavy metal resistance genes) were identified in addition. While growth, biofilm formation, desiccation resilience, serum survival, and heavy metal resistance were comparable to several control strains, results from siderophore secretion and hypermucoviscosity experiments revealed superiority of the ST307 clone, similar to an archetypical, hypervirulent K. pneumoniae strain (hvKP1). Conclusions The combination of extensive drug resistance and virulence, partly conferred through a “mosaic” plasmid carrying both antibiotic resistance and hypervirulence-associated features, demonstrates serious public health implications.



2018 ◽  
Vol 62 (5) ◽  
Author(s):  
Helen Billman-Jacobe ◽  
Yuhong Liu ◽  
Ruth Haites ◽  
Tom Weaver ◽  
Lily Robinson ◽  
...  

ABSTRACTDetailed annotation of an IncHI2 plasmid, pSTM6-275, fromSalmonella entericaserotype 1,4,5,12:i:- strain TW-Stm6 revealed a composite structure, including antimicrobial resistance genes on mobile genetic elements. The plasmid was thermosensitive for transfer toEscherichia coliand conferred reduced susceptibility to antibiotics, copper sulfate, and silver nitrate. Metal ion susceptibility was dependent on physiological conditions, giving an insight into the environments where this trait might confer a fitness advantage.



Genes ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 1025
Author(s):  
Shaohua Zhao ◽  
Cong Li ◽  
Chih-Hao Hsu ◽  
Gregory H. Tyson ◽  
Errol Strain ◽  
...  

Salmonella is a leading cause of bacterial infections in animals and humans. We sequenced a collection of 450 Salmonella strains from diseased animals to better understand the genetic makeup of their virulence and resistance features. The presence of Salmonella pathogenicity islands (SPIs) varied by serotype. S. Enteritidis carried the most SPIs (n = 15), while S. Mbandaka, S. Cerro, S. Meleagridis, and S. Havana carried the least (n = 10). S. Typhimurium, S. Choleraesuis, S. I 4,5,12:i:-, and S. Enteritidis each contained the spv operon on IncFII or IncFII-IncFIB hybrid plasmids. Two S. IIIa carried a spv operon with spvD deletion on the chromosome. Twelve plasmid types including 24 hybrid plasmids were identified. IncA/C was frequently associated with S. Newport (83%) and S. Agona (100%) from bovine, whereas IncFII (100%), IncFIB (100%), and IncQ1 (94%) were seen in S. Choleraesuis from swine. IncX (100%) was detected in all S. Kentucky from chicken. A total of 60 antimicrobial resistance genes (ARGs), four disinfectant resistances genes (DRGs) and 33 heavy metal resistance genes (HMRGs) were identified. The Salmonella strains from sick animals contained various SPIs, resistance genes and plasmid types based on the serotype and source of the isolates. Such complicated genomic structures shed light on the strain characteristics contributing to the severity of disease and treatment failures in Salmonella infections, including those causing illnesses in animals.



Author(s):  
Kashaf Junaid ◽  
Hasan Ejaz ◽  
Iram Asim ◽  
Sonia Younas ◽  
Humaira Yasmeen ◽  
...  

This study evaluates bacteriological profiles in ready-to-eat (RTE) foods and assesses antibiotic resistance, extended-spectrum β-lactamase (ESBL) production by gram-negative bacteria, and heavy metal tolerance. In total, 436 retail food samples were collected and cultured. The isolates were screened for ESBL production and molecular detection of ESBL-encoding genes. Furthermore, all isolates were evaluated for heavy metal tolerance. From 352 culture-positive samples, 406 g-negative bacteria were identified. Raw food samples were more often contaminated than refined food (84.71% vs. 76.32%). The predominant isolates were Klebsiella pneumoniae (n = 76), Enterobacter cloacae (n = 58), and Escherichia coli (n = 56). Overall, the percentage of ESBL producers was higher in raw food samples, although higher occurrences of ESBL-producing E. coli (p = 0.01) and Pseudomonas aeruginosa (p = 0.02) were observed in processed food samples. However, the prevalence of ESBL-producing Citrobacter freundii in raw food samples was high (p = 0.03). Among the isolates, 55% were blaCTX-M, 26% were blaSHV, and 19% were blaTEM. Notably, heavy metal resistance was highly prevalent in ESBL producers. These findings demonstrate that retail food samples are exposed to contaminants including antibiotics and heavy metals, endangering consumers.



2021 ◽  
Vol 9 (3) ◽  
pp. 499
Author(s):  
Majid Rasool Kamli ◽  
Nada A. Y. Alzahrani ◽  
Nahid H. Hajrah ◽  
Jamal S. M. Sabir ◽  
Adeel Malik

Bacteria belonging to the genus Aneurinibacillus within the family Paenibacillaceae are Gram-positive, endospore-forming, and rod-shaped bacteria inhabiting diverse environments. Currently, there are eight validly described species of Aneurinibacillus; however, several unclassified species have also been reported. Aneurinibacillus spp. have shown the potential for producing secondary metabolites (SMs) and demonstrated diverse types of enzyme activities. These features make them promising candidates with industrial implications. At present, genomes of 9 unique species from the genus Aneurinibacillus are available, which can be utilized to decipher invaluable information on their biosynthetic potential as well as enzyme activities. In this work, we performed the comparative genome analyses of nine Aneurinibacillus species representing the first such comprehensive study of this genus at the genome level. We focused on discovering the biosynthetic, biodegradation, and heavy metal resistance potential of this under-investigated genus. The results indicate that the genomes of Aneurinibacillus contain SM-producing regions with diverse bioactivities, including antimicrobial and antiviral activities. Several carbohydrate-active enzymes (CAZymes) and genes involved in heavy metal resistance were also identified. Additionally, a broad range of enzyme classes were also identified in the Aneurinibacillus pan-genomes, making this group of bacteria potential candidates for future investigations with industrial applications.



1995 ◽  
Vol 18 (3) ◽  
pp. 191-203 ◽  
Author(s):  
Eva M. Top ◽  
Helene Rore ◽  
Jean-Marc Collard ◽  
Veerle Gellens ◽  
Galina Slobodkina ◽  
...  


2021 ◽  
Vol 19 ◽  
Author(s):  
Manzar Alam ◽  
Mohd Imran ◽  
Syed Sayeed Ahmad

Background: Microbial resistance to antibiotics and heavy metals is a rising problem in the world today. All the Proteus vulgaris isolates showed their MIC in between 50-1600 µg/ml. Of 70% and 46% of the isolates showed their MIC at 800-1200 µg/ml against Zn2+ and Cu2+ while 80% of the isolates showed their MIC at 100-200 µg/ml against Ni2+, respectively. All Proteus vulgaris isolates also exhibited multiple resistance patterns (2-7 heavy metals) in different combination of metals. The Multi metal resistance Index (MHMR) ranges were found (0.04-0.5). Methods: A high level of antibiotics resistance was observed against Methicillin (100%) and least to Oflaxicin (6%), Gentamycine and Neomycin (10%). All Proteus vulgaris isolates also showed multiple drug resistance patterns (2-12 antibiotics) in different combination of antibiotics. The MAR index ranges were found (0.02-0.7). Of 98%, 84% and 80% of the total isolates showed urease, gelatinase and amylase activity. Results: The Proteus vulgaris isolates contained plasmid of size ranging from 42.5 to 57.0kb and molecular weight of plasmids ranged from 27.2 to 37.0 MD. Incidences of resistance transfer, 7 pairs of isolates were assessed for the transfer of the antibiotic/ heavy metal resistance markers. The higher (4.4x10-1 and 3.4x10-1) transfer frequency was observed among antibiotic and heavy metal while lower transfer frequency were (5.0x10-2 and 1.0x10-2) showed against antibiotic and heavy metal in both the medium from the entire site tested, respectively. Conclusion: Indicating the high threat of environmental pollution and appearance of heavy metal resistance which may support the enlargement of resistance to antibiotics among the pathogens.



2018 ◽  
pp. 15-42
Author(s):  
Pallavee Srivastava ◽  
Meenal Kowshik


2022 ◽  
Author(s):  
Madhuri Girdhar ◽  
Zeba Tabassum ◽  
Kopal Singh ◽  
Anand Mohan

Heavy metals accumulated the earth crust and causes extreme pollution. Accumulation of rich concentrations of heavy metals in environments can cause various human diseases which risks health and high ecological issues. Mercury, arsenic, lead, silver, cadmium, chromium, etc. are some heavy metals harmful to organisms at even very low concentration. Heavy metal pollution is increasing day by day due to industrialization, urbanization, mining, volcanic eruptions, weathering of rocks, etc. Different microbial strains have developed very efficient and unique mechanisms for tolerating heavy metals in polluted sites with eco-friendly techniques. Heavy metals are group of metals with density more than 5 g/cm3. Microorganisms are generally present in contaminated sites of heavy metals and they develop new strategies which are metabolism dependent or independent to tackle with the adverse effects of heavy metals. Bacteria, Algae, Fungi, Cyanobacteria uses in bioremediation technique and acts a biosorbent. Removal of heavy metal from contaminated sites using microbial strains is cheaper alternative. Mostly species involved in bioremediation include Enterobacter and Pseudomonas species and some of bacillus species too in bacteria. Aspergillus and Penicillin species used in heavy metal resistance in fungi. Various species of the brown algae and Cyanobacteria shows resistance in algae.



Sign in / Sign up

Export Citation Format

Share Document