In vitro evaluation of mercury (Hg2+) effects on biofilm formation by clinical and environmental isolates of Klebsiella pneumoniae

Araújo, Lívia Caroline Alexandre de; Purificação-Júnior, Antônio Fernando da; Silva, Sivoneide Maria da; Lópes, Ana Catarina de Souza; Veras, Dyana Leal; Alves, Luíz Carlos; Santos, Fábio Brayner dos; Napoleão, Thiago Henrique; Correia, Maria Tereza dos Santos; Silva, Márcia Vanusa da; Oliva, Maria Luiza Vilela; Oliveira, Maria Betânia Melo de

doi:10.1016/j.ecoenv.2018.11.036

Cited by 24 publications

(12 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…in the presence of mercury (Hg 2+ ). Similarly, Araújo et al [49] verified an increase in biofilm formation in Klebsiella pneumoniae isolates obtained from an impacted urban stream. However, other studies show that depending on the metal and its concentration, biofilm formation may be reduced [50,51].…”

Section: Effects Of Heavy Metals On Biofilmmentioning

confidence: 82%

“…In addition to changes in cell adhesion, exposure to heavy metals may cause structural changes in the biofilm extracellular polymeric substance (EPS) matrix. Araújo et al [49] verified by scanning microscopy, the increase of EPS in K. pneumoniae biofilms formed when exposed to subinhibitory mercury concentrations (Hg 2+ ). Sheng et al [58] also demonstrated that heavy metals stimulate EPS production in Rhodopseudomonas acidophila.…”

Section: Effects Of Heavy Metals On Biofilmmentioning

confidence: 92%

“…that presented the merA gene were resistant to different antibiotics such as tetracycline, trimethoprim, nalixidic acid, and streptomycin. Araújo et al [49] verified, when comparing isolates of K. pneumoniae, that the isolate that presented the merA gene was resistant to the highest number of antimicrobials and presented the minimum inhibitory concentration (MIC) value up to four times higher than the others, suggesting a co-resistance mechanism for mercury and antimicrobials tested.…”

Section: Heavy Metal Resistancementioning

confidence: 99%

See 2 more Smart Citations

Effect of Heavy Metals on the Biofilm Formed by Microorganisms from Impacted Aquatic Environments

Araújo¹,

Oliveira²

2020

Bacterial Biofilms

View full text Add to dashboard Cite

The aquatic environment is highly complex and diverse, consisting of several types of ecosystems that are dynamic products of complex interactions between biotic and abiotic components. Changes in the physical and chemical properties of these ecosystems can significantly affect the balance of life forms present, especially in their microbiota. Among the main pollutants present in these environments are heavy metals. Several studies demonstrate the effects of these minerals on the structure and function of microbial communities, which may develop adaptation mechanisms for survival and permanence in these sites. In addition, the resistance to heavy metals may contribute to the evolution of resistance genes to the different types of antimicrobials due to the increase of the selective pressure in the environment, becoming a public health problem. One of the adaptive mechanisms present in bacteria from impacted environments that has been frequently investigated is the formation of biofilms. Recent studies have reported significant changes in the structure and amount of biofilm formed in the presence of different metals, and consequently, an increase in the tolerance to these pollutants and antimicrobials. This review will discuss the effects of some metals on bacterial biofilms and their consequences for the marine environment.

show abstract

Section: Effects Of Heavy Metals On Biofilmmentioning

confidence: 82%

Section: Effects Of Heavy Metals On Biofilmmentioning

confidence: 92%

Section: Heavy Metal Resistancementioning

confidence: 99%

See 1 more Smart Citation

Effect of Heavy Metals on the Biofilm Formed by Microorganisms from Impacted Aquatic Environments

Araújo¹,

Oliveira²

2020

Bacterial Biofilms

View full text Add to dashboard Cite

show abstract

“…The biofilm-forming ability of the isolates were also quantitated as previously described [23]. Briefly, 96-well polystyrene, flat-bottom microtiter plates (Tarsons Products Pvt.…”

Section: Analyses Of Biofilm Formationmentioning

confidence: 99%

“…To visualize bacterial membrane damage following treatment with LA, SEM was carried out as previously described [23]. JNM11.C4 cells were treated with 0.150% and 0.225% LA in triplicate, as described above for 3 h, while untreated and cells treated with 50 µg/mL MRP (Pharma Impex Laboratories Pvt.…”

Section: Scanning Electron Microscopy (Sem)mentioning

confidence: 99%

Bactericidal Activity of Lactic Acid against Clinical, Carbapenem-Hydrolyzing, Multi-Drug-Resistant Klebsiella pneumoniae Planktonic and Biofilm-Forming Cells

2019

View full text Add to dashboard Cite

: Carbapenem resistant Klebsiella pneumoniae has been highlighted to be a critical pathogen by the World Health Organization. The objectives of this study were to assess the efficacy of lactic acid (LA) against planktonic cells and biofilms formed by carbapenem-hydrolyzing K. pneumoniae isolates obtained from the nares of preterm neonates. Time-kill assays with graded percentages of (v/v) LA in water were initially carried out against planktonic cells of a meropenem (MRP)-resistant K. pneumoniae isolate, JNM11.C4. The efficacy parameters such as optimal incubation time and minimum inhibitory concentration were determined by comparing colony-forming unit counts (log(10)CFU). Scanning electron microscopy was used to visualize cell damage. Likewise, JNM11.C4 biofilms were treated with graded series of (v/v) LA. Six carbapenem-hydrolyzing isolates were next used to validate the results. A reduction of 3.6 ± 0.6 log(10) CFU/mL in JNM11.C4 planktonic cells and >3 ± 0.03log(10) CFU/mL in biofilm-forming cells were observed using 0.225% and 2% LA, respectively, after three hours. Similar decreases in viable cell-counts were observed both in the case of planktonic (˃3.6 ± 0.3log(10) CFU/mL) and biofilm-forming cells (3.8 ± 0.3log(10) CFU/mL) across all the six clinical isolates. These results indicate that LA is an effective antimicrobial against planktonic carbapenem-hydrolyzing K. pneumoniae cells and biofilms.

show abstract

Biofilm and metallothioneins: A dual approach to bioremediate the heavy metal menace

Roy,

Maitra,

Sarkar

et al. 2023

Environmental Quality Mgmt

View full text Add to dashboard Cite

Metallothioneins are a class of proteins produced by both prokaryotes and eukaryotes, having low molecular weight and abundant cysteine residues. These proteins play a humongous role in binding, sequestration, and even buffering of the intracellular metal ions. Though they are a wide class of proteins, much of them are yet to be explored. Their metal binding attribute is unique and they form distinctive metal‐thiolate clusters. They have also been known to have ROS scavenging activities due to the presence of the cysteine residues. Phytochelatins also play major roles in metal sequestration pathways. Biofilms on the other hand are clusters of bacterial cells surrounded by an extracellular matrix of polymeric substances secreted by the bacteria themselves. Biofilms play multiple roles, from nutrient sequestration, stress resistance to surface adherence. But lesser explored arenas include assistance in heavy metal trapping and bio‐remediation. Researchers have conducted studies that have demonstrated increased metal trapping, resistance and uptake in biofilm forming strains than non‐biofilm forming mutants. Therefore, this study would explore the dual role of metallothionein and biofilm in their activity of metal sequestration and heavy metal remediation and provide certain insights so as to keenly understand the correlations between the two.

show abstract

In vitro evaluation of mercury (Hg2+) effects on biofilm formation by clinical and environmental isolates of Klebsiella pneumoniae

Cited by 24 publications

References 51 publications

Effect of Heavy Metals on the Biofilm Formed by Microorganisms from Impacted Aquatic Environments

Effect of Heavy Metals on the Biofilm Formed by Microorganisms from Impacted Aquatic Environments

Bactericidal Activity of Lactic Acid against Clinical, Carbapenem-Hydrolyzing, Multi-Drug-Resistant Klebsiella pneumoniae Planktonic and Biofilm-Forming Cells

Biofilm and metallothioneins: A dual approach to bioremediate the heavy metal menace

Contact Info

Product

Resources

About