Studies on the biofilm produced by Pseudomonas aeruginosa grown in different metal fatty acid salt media and its application in biodegradation of fatty acids and bioremediation of heavy metal ions

Metal fatty acid salts (MFAS) in untreated industrial effluents cause environmental pollution. The use of biocompatible agents for remediation may help in reducing the harm caused to the ambient aquatic organism. Pseudomonas aeruginosa is a ubiquitous organism that thrives under harsh conditions and is resistant to toxic metal ions. The present study shows a proof-of-concept of using this organism in the biodegradation of MFAS. MFAS were prepared and we studied their effect on the growth of the planktonic form and the formation of biofilm by P. aeruginosa. We observed biofilm formation in the presence of all the MFAS when used as the sole carbon source, albeit the quantity of biofilm formed in the presence of cadmium and copper was less. There was no effect on the planktonic form of the organism but the formation of biofilm increased in the presence of magnesium palmitate. This study shows that metal ions play a pivotal role in the formation of biofilm. HPLC (high-performance liquid chromatography) analysis of the biofilm polysaccharide showed that hexose sugar was a major component when compared with pentose sugar. The structure of biofilm polysaccharide and the coordination of the metal ion with the biofilm polysaccharide were confirmed by FTIR (Fourier transform infrared spectroscopy) and Raman spectroscopy.

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Functional characterization of the dimerization domain of the ferric uptake regulator (Fur) of Pseudomonas aeruginosa

Biochemical Journal ◽

10.1042/bj20061168 ◽

2006 ◽

Vol 400 (3) ◽

pp. 385-392 ◽

Cited By ~ 4

Author(s):

Erdeni Bai ◽

Federico I. Rosell ◽

Bao Lige ◽

Marcia R. Mauk ◽

Barbara Lelj-Garolla ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Metal Ions ◽

Binding Site ◽

Metal Ion ◽

Association Constants ◽

Ion Binding ◽

Ferric Uptake Regulator ◽

Metal Ion Binding ◽

Dimerization Domain ◽

High Affinity

The functional properties of the recombinant C-terminal dimerization domain of the Pseudomonas aeruginosa Fur (ferric uptake regulator) protein expressed in and purified from Escherichia coli have been evaluated. Sedimentation velocity measurements demonstrate that this domain is dimeric, and the UV CD spectrum is consistent with a secondary structure similar to that observed for the corresponding region of the crystallographically characterized wild-type protein. The thermal stability of the domain as determined by CD spectroscopy decreases significantly as pH is increased and increases significantly as metal ions are added. Potentiometric titrations (pH 6.5) establish that the domain possesses a high-affinity and a low-affinity binding site for metal ions. The high-affinity (sensory) binding site demonstrates association constants (KA) of 10(±7)×106, 5.7(±3)×106, 2.0(±2)×106 and 2.0(±3)×104 M−1 for Ni2+, Zn2+, Co2+ and Mn2+ respectively, while the low-affinity (structural) site exhibits association constants of 1.3(±2)×106, 3.2(±2)×104, 1.76(±1)×105 and 1.5(±2)×103 M−1 respectively for the same metal ions (pH 6.5, 300 mM NaCl, 25 °C). The stability of metal ion binding to the sensory site follows the Irving–Williams order, while metal ion binding to the partial sensory site present in the domain does not. Fluorescence experiments indicate that the quenching resulting from binding of Co2+ is reversed by subsequent titration with Zn2+. We conclude that the domain is a reasonable model for many properties of the full-length protein and is amenable to some analyses that the limited solubility of the full-length protein prevents.

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Nanocelllulose Based Adsorbents for Heavy Metal Ions Removal

10.21203/rs.3.rs-594942/v1 ◽

2021 ◽

Author(s):

Rongrong Si ◽

Daiqi Wang ◽

Yehong Chen ◽

Dongmei Yu ◽

Qijun Ding ◽

...

Keyword(s):

Heavy Metal ◽

Metal Ions ◽

Heavy Ions ◽

Metal Ion ◽

Heavy Metal Ions ◽

High Performance ◽

Advanced Technologies ◽

Good Biocompatibility ◽

Heavy Metal Ions Removal ◽

Metal Ions Removal

Abstract Heavy metal ion pollutions are of serious threat for our human health, and advanced technologies on removal of heavy metal ions in water or soil are in the focus of intensive research worldwide. Nanocellulose based adsorbents are emerging as an environmentally friendly appealing materials platform for heavy metal ions removal as nanocellulose has higher specific surface area, excellent mechanical properties and good biocompatibility. In this review, we briefly compare the differences of three kinds of nanocellulose and their preparation method. Then we cover the most recent work on nanocellulose based adsorbents for heavy metal ions removal, and present an in-depth discussion of the modification technologies for nanocellulose in assembling high performance heavy ions adsorbent process. By introducing functional groups, such as amino, carboxyl, phenolic hydroxyl, and thiol, the nanocellulose based adsorbents not only remove single heavy metal ions through ion exchange, chelation/complexation/coordination, electrostatic attraction, hydrophobic actions, binding affinity and redox reactions, but also can selectively adsorb multiple heavy ions in water. Finally, some challenges of nanocellulose based adsorbents for heavy metal ions are also prospected. We anticipate that the review supplies some guides for nanocellulose based adsorbents applied in heavy metal ions removal field.

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Characterization of Putative Virulence Factors of Pseudomonas aeruginosa Strain RBS Isolated from a Saltern, Tunisia: Effect of Metal Ion Cofactors on the Structure and the Activity of LasB

BioMed Research International ◽

10.1155/2020/6047528 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13

Author(s):

E. Rigane ◽

R. Dutoit ◽

S. Matthijs ◽

N. Brandt ◽

S. Flahaut ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Metal Ions ◽

Virulence Factors ◽

Binding Sites ◽

Biofilm Formation ◽

Metal Ion ◽

Enzyme Stability ◽

Inhibitory Effect ◽

Ion Binding ◽

Metal Ion Binding

Pseudomonas aeruginosa is a ubiquitous Gram-negative bacterium able to survive in diverse environments such as soil, plants, freshwater, and seawater. P. aeruginosa can be an opportunistic pathogen to humans when their immune system is deficient. Its pathogenicity may be linked to the production of virulence factors. We isolated P. aeruginosa strain RBS from the saltern of Sfax in Tunisia. In this study, we characterized the halotolerance, antibiotic susceptibility, and some virulence factors of strain RBS. High NaCl concentrations inhibited growth and motility. However, biofilm formation was enhanced to protect bacteria against salt stress. Among the 18 antibiotics tested, quinolones and tetracycline showed a significant inhibitory effect on growth, motility, and biofilm formation of strain RBS. β-Lactams, however, did not have any inhibitory effect on neither bacterial growth nor motility. In some cases, resistance was due, in part, to biofilm formation. We also showed that RBS produces two proteases, LasB and AprA, which have been shown to be implicated in host infection. LasB was further characterized to study the role of metal ions in enzyme stability. It possesses two distinct metal ion-binding sites coordinating a calcium and a zinc ion. The effect of metal ion chelation was evaluated as well as substitutions of residues involved in metal ion binding. Impairing metal ion binding of LasB led to a loss of activity and a sharp decrease of stability. Our findings suggest that the binding of both metal ions is interdependent as the two metal ions’ binding sites are linked via a hydrogen bond network.

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Effect of divalent metal ions on annexin-mediated aggregation of asolectin liposomes.

Acta Biochimica Polonica ◽

10.18388/abp.2000_3988 ◽

2000 ◽

Vol 47 (3) ◽

pp. 675-683 ◽

Cited By ~ 1

Author(s):

V I Mel'gunov ◽

E I Akimova ◽

K S Krasavchenko

Keyword(s):

Metal Ions ◽

Metal Ion ◽

Relative Concentration ◽

Toxic Metal ◽

Transition Metal Ions ◽

Divalent Metal ◽

Divalent Metal Ions ◽

Large Unilamellar Vesicles ◽

Protein Molecules ◽

Divalent Metal Ion

Annexins belong to a family of Ca2+- and phospholipid-binding proteins that can mediate the aggregation of granules and vesicles in the presence of Ca2+. We have studied the effects of different divalent metal ions on annexin-mediated aggregation of liposomes using annexins isolated from rabbit liver and large unilamellar vesicles prepared from soybean asolectin II-S. In the course of these studies, we have found that annexin-mediated aggregation of liposomes can be driven by various earth and transition metal ions other than Ca2+. The ability of metal ions to induce annexin-mediated aggregation decreases in the order: Cd2+ > Ba2+, Sr2+ > Ca2+ > Mn2+ > Ni2+ > Co2+. Annexin-mediated aggregation of vesicles is more selective to metal ions than the binding of annexins to membranes. We speculate that not every type of divalent metal ion can induce conformational change sufficient to promote the interaction of annexins either with two opposing membranes or with opposing protein molecules. Relative concentration ratios of metal ions in the intimate environment may be crucial for the functioning of annexins within specialized tissues and after treatment with toxic metal ions.

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Greener Method for the Removal of Toxic Metal Ions from the Wastewater by Application of Agricultural Waste as an Adsorbent

Water ◽

10.3390/w10101316 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1316 ◽

Cited By ~ 9

Author(s):

Rabia Baby Shaikh ◽

Bullo Saifullah ◽

Fawad Rehman ◽

Ruqia Iqbal Shaikh

Keyword(s):

Metal Ions ◽

Metal Ion ◽

Low Cost ◽

Agricultural Waste ◽

Toxic Metal ◽

Freundlich Isotherm ◽

Agitation Rate ◽

Before And After ◽

Economic Barriers

The presence of inorganic pollutants such as metal ions (Ni2+, Pb2+, Cr6+) in water, probably by long-term geochemical changes and from the effluents of various industries, causes diseases and disorders (e.g., cancer, neurodegenerative diseases, muscular dystrophy, hepatitis, and multiple sclerosis). Conventional methods for their removal are limited by technical and economic barriers. In biosorption, low-cost and efficient biomaterials are used for this purpose. In this study, Brassica Campestris stems from the agriculture waste and has been used for the removal of Ni2+, Cr6+ and Pb2+ ions from an aqueous solution containing all the ions. Effect of different parameters, e.g., pH, contact time, metal ion initial concentration, adsorbent dose, agitation rate and temperature were analyzed and optimized. The adsorbent worked well for removal of the Pb2+ and Cr6+ as compared to Ni2+. The atomic absorption spectrophotometer (AAS) and FTIR investigation of adsorbent before and after shows a clear difference in the adsorbent capability. The highest adsorption percentage was found at 98%, 91%, and 49% respectively, under the optimized parameters. Furthermore, the Langmuir isotherm was found better in fitting to the experimental data than that of the Freundlich isotherm.

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Biosorptive Removal of Cadmium(II) and Copper(II) Using Microwave-Assisted Thiourea-Modified Sorghum bicolor Agrowaste

Journal of Chemistry ◽

10.1155/2020/8269643 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Muhammad Salman ◽

Rabia Rehman ◽

Umar Farooq ◽

Anum Tahir ◽

Liviu Mitu

Keyword(s):

Metal Ions ◽

Sorghum Bicolor ◽

Metal Ion ◽

Toxic Metal ◽

Order Kinetic ◽

Metal Ion Removal ◽

Ion Removal ◽

Removal Capacity ◽

Biosorption Process ◽

Ft Ir

Sorghum bicolor (S.B.) is used in this work for preparing chemically modified adsorbent for toxic metal ions, i.e., cadmium(II) and copper(II). Thiourea is selected for chemical modification of this plant waste by microwave solid fusion methodology, so that its chelating ability for metal ions can be enhanced in both acidic and basic conditions, in a cheaper and quicker way. Characterization was carried out by different physiochemical means using FT-IR, SEM, etc. An increase in pHpzc value was observed in TSB, which is confirmed by FT-IR analysis. The effect of biosorption process parameters was also studied and found that maximum removal of these toxic ions occurred in slightly acidic pH (5-6) conditions, following pseudo-second-order kinetic model. Boyd plots indicated that film dispersion mode was the rate-determining step. Langmuir model indicated that the maximum metal ion removal capacity of TSB was 17.241 mg/g and 15.151 mg/g for cadmium(II) and copper(II) ions. So, TSB can be used on a larger scale for toxic metal ion removal by Sorghum bicolor waste in a cleaner way.

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Toxic metal ions in water and their prevalence in Uttarakhand, India

Water Science & Technology Water Supply ◽

10.2166/ws.2012.052 ◽

2012 ◽

Vol 12 (6) ◽

pp. 773-782 ◽

Cited By ~ 2

Author(s):

Vinod Kumar Gupta ◽

Rajendra Dobhal ◽

Arunima Nayak ◽

Shilpi Agarwal ◽

Devi Prasad Uniyal ◽

...

Keyword(s):

Metal Ions ◽

Metal Ion ◽

Toxic Metal ◽

Industrial Wastes ◽

World Health ◽

Toxic Metal Ions ◽

Set Up ◽

Health Organization ◽

Almost All

Developmental activities, geological reasons and mixing of industrial wastes are responsible for the deteriorating quality of surface and ground water in the Himalayan state of Uttarakhand. The drinking water sources of 13 districts of Uttarakhand have been assessed for the presence of four toxic metal ions (arsenic, cadmium, chromium and lead). The health aspects of the four metal ions have also been reviewed according to the prescribed limits set up by the Bureau of Indian Standards (BIS) and World Health Organization (WHO). The present study reveals the absence of arsenic at almost all stations. Cadmium has been found only at Rudrapur, whereas chromium is found to be present in more than prescribed limits, in Kolti, Mussoorie and Dehradun. Significant presence of lead in the six districts of the state is indicative of the fact that proper management strategy of toxic metal ion remediation is required. Chromium and lead have exceeded the prescribed limit in 1.3 and 4.5% samples, respectively. However, as per BIS standard, cadmium is higher than the prescribed limit in 0.6% samples but according to the WHO standard, cadmium has exceeded in about 26% samples. Out of the total 156 samples analyzed, 6.4 and 33.3% samples have been found to possess the toxic metal ions in more than the prescribed limits as per BIS and WHO guidelines, respectively.

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Influence of Metal Ions on Model Protoamphiphilic Vesicular Systems: Insights from Laboratory and Analogue Studies

Life ◽

10.3390/life11121413 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1413

Author(s):

Manesh Prakash Joshi ◽

Luke Steller ◽

Martin J. Van Kranendonk ◽

Sudha Rajamani

Keyword(s):

Fatty Acid ◽

Metal Ions ◽

Self Assembly ◽

Metal Ion ◽

Hot Spring ◽

Divalent Cations ◽

Microscopic Analysis ◽

Monovalent Cation ◽

The Self ◽

Vesicle Formation

Metal ions strongly affect the self-assembly and stability of membranes composed of prebiotically relevant amphiphiles (protoamphiphiles). Therefore, evaluating the behavior of such amphiphiles in the presence of ions is a crucial step towards assessing their potential as model protocell compartments. We have recently reported vesicle formation by N-acyl amino acids (NAAs), an interesting class of protoamphiphiles containing an amino acid linked to a fatty acid via an amide linkage. Herein, we explore the effect of ions on the self-assembly and stability of model N-oleoyl glycine (NOG)-based membranes. Microscopic analysis showed that the blended membranes of NOG and Glycerol 1-monooleate (GMO) were more stable than pure NOG vesicles, both in the presence of monovalent and divalent cations, with the overall vesicle stability being 100-fold higher in the presence of a monovalent cation. Furthermore, both pure NOG and NOG + GMO mixed systems were able to self-assemble into vesicles in natural water samples containing multiple ions that were collected from active hot spring sites. Our study reveals that several aspects of the metal ion stability of NAA-based membranes are comparable to those of fatty acid-based systems, while also confirming the robustness of compositionally heterogeneous membranes towards high metal ion concentrations. Pertinently, the vesicle formation by NAA-based systems in terrestrial hot spring samples indicates the conduciveness of these low ionic strength freshwater systems for facilitating prebiotic membrane-assembly processes. This further highlights their potential to serve as a plausible niche for the emergence of cellular life on the early Earth.

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Cholinesterase from the Liver of Diodon hystrix for Detection of Metal Ions

Pertanika Journal of Science and Technology ◽

10.47836/pjst.28.s2.09 ◽

2020 ◽

Vol 28 (S2) ◽

Author(s):

Noreen Nordin ◽

Ronaldo Ron Cletus ◽

Mohd Khalizan Sabullah ◽

Siti Aishah Muhammad Khalidi ◽

Rahmath Abdulla ◽

...

Keyword(s):

Heavy Metals ◽

Metal Ions ◽

Metal Ion ◽

Industrial Effluents ◽

High Technology ◽

Effective Coefficient ◽

Preliminary Screening ◽

Acetylthiocholine Iodide ◽

Foreign Materials ◽

Living Organisms

The discharge of industrial effluents into nearby water bodies affects the inhabitants including living organisms. The presence of foreign materials such as heavy metals can be a threat to the ecosystem as they are enormously carcinogenic even though in minute concentration. Hence, an economical and time-efficient preliminary screening test is crucial to be developed for the detection of heavy metals, prior to employment of high technology instruments. In this study, cholinesterase (ChE) from Sabah porcupine fish, Diodon hystrix was purified to test for its potential as an alternative biosensor in detecting metal ions. Few enzymatic parameters including specificity of substrate, temperature and pH were applied to determine its optimal enzymatic activity. ChE enzyme was found to be more sensitive towards the presence of substrate, butyrylthiocholine iodide (BTC), in contrast to acetylthiocholine iodide (ATC) and propionylthiocholine iodide (PTC) with the effective coefficient at 7193, 3680.15 and 2965.26 Vmax/Km, respectively. Moreover, the extracted ChE enzyme showed the optimum activity at pH 9 of 0.1 M Tris-HCl and at 25°C to 30°C range of temperature. When subjected to heavy metals, ChE enzyme was significantly inhibited as the enzyme activity was reduced in the sequence of Hg > Ag > Cr > Cu > Cd > Pb ≥ Zn > As. As a conclusion, the partially purified ChE enzyme proved its sensitivity towards metal ion exposure and can be used as an alternative method in screening the level of contamination in the environment.

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Arylphosphonate-Tethered Porphyrins: Fluorescence Silencing Speaks a Metal Language in Living Enterocyte

10.26434/chemrxiv.13369835.v1 ◽

2020 ◽

Author(s):

Claudia Keil ◽

Julia Klein ◽

Franz-Josef Schmitt ◽

Yunus Zorlu ◽

Hajo Haase ◽

...

Keyword(s):

Metal Ions ◽

Metal Ion ◽

Toxic Metal ◽

Emission Spectra ◽

Cellular Membrane ◽

Fluorescence Decay ◽

Ion Concentrations ◽

Turn On ◽

Sensor Platform ◽

Porphyrin Core

We report the application of a highly versatile and engineerable novel sensor platform to monitor biologically significant and toxic metal ions in live human Caco-2 enterocytes. The extended conjugation between the fluorescent porphyrin core and metal ions via aromatic phenylphosphonic acid tethers generates a unique turn off and turn on fluorescence and, in addition, shifts in absorption and emission spectra for zinc, cobalt, cadmium and mercury. The reported fluorescent probes p-H8TPPA and m-H8TPPA can monitor a wide range of metal ion concentrations via fluorescence titration and also via fluorescence decay curves. Cu and Zn-induced turn off fluorescence can be differentially reversed by the addition of common chelators. Both p-H8TPPA and m-H8TPPA readily pass the mammalian cellular membrane due to their amphipathic character as confirmed by confocal microscopic imaging of living enterocytes.

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