scholarly journals The role of multivalent cations in the uptake and oxidation of glucose by Pseudomonas fluorescens (Short Communication)

1973 ◽  
Vol 136 (2) ◽  
pp. 429-431
Author(s):  
Cynthia A. Walker ◽  
Norman N. Durham
Keyword(s):  
Pseudomonas Fluorescens ◽  
Metal Ion ◽  
Short Communication ◽  
Enzymic Activity ◽  
Membrane Stabilization ◽  
Oxidation Of Glucose

The effects of Mg2+, Mn2+, Ca2+ and Fe3+ on the uptake and oxidation of glucose in induced and non-induced Pseudomonas fluorescens cells were studied. Mg2+ is the most effective single metal ion in the uptake of glucose by the cell, and it functions in membrane stabilization and enzymic activity. Ca2+ will substitute for Mg2+, but Mn2+ and Fe3+ will not.

scholarly journals Role of hepcidin in oxidative stress and cell death of cultured mouse renal collecting duct cells: protection against iron and sensitization to cadmium

2021 ◽  
Author(s):  
Stephanie Probst ◽  
Johannes Fels ◽  
Bettina Scharner ◽  
Natascha A. Wolff ◽  
Eleni Roussa ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Death ◽  
Cell Fate ◽  
Catalase Activity ◽  
Metal Ion ◽  
Iron Homeostasis ◽  
Collecting Duct ◽  
Duct Cell ◽  
Plasmid Transfection

AbstractThe liver hormone hepcidin regulates systemic iron homeostasis. Hepcidin is also expressed by the kidney, but exclusively in distal nephron segments. Several studies suggest hepcidin protects against kidney damage involving Fe2+ overload. The nephrotoxic non-essential metal ion Cd2+ can displace Fe2+ from cellular biomolecules, causing oxidative stress and cell death. The role of hepcidin in Fe2+ and Cd2+ toxicity was assessed in mouse renal cortical [mCCD(cl.1)] and inner medullary [mIMCD3] collecting duct cell lines. Cells were exposed to equipotent Cd2+ (0.5–5 μmol/l) and/or Fe2+ (50–100 μmol/l) for 4–24 h. Hepcidin (Hamp1) was transiently silenced by RNAi or overexpressed by plasmid transfection. Hepcidin or catalase expression were evaluated by RT-PCR, qPCR, immunoblotting or immunofluorescence microscopy, and cell fate by MTT, apoptosis and necrosis assays. Reactive oxygen species (ROS) were detected using CellROX™ Green and catalase activity by fluorometry. Hepcidin upregulation protected against Fe2+-induced mIMCD3 cell death by increasing catalase activity and reducing ROS, but exacerbated Cd2+-induced catalase dysfunction, increasing ROS and cell death. Opposite effects were observed with Hamp1 siRNA. Similar to Hamp1 silencing, increased intracellular Fe2+ prevented Cd2+ damage, ROS formation and catalase disruption whereas chelation of intracellular Fe2+ with desferrioxamine augmented Cd2+ damage, corresponding to hepcidin upregulation. Comparable effects were observed in mCCD(cl.1) cells, indicating equivalent functions of renal hepcidin in different collecting duct segments. In conclusion, hepcidin likely binds Fe2+, but not Cd2+. Because Fe2+ and Cd2+ compete for functional binding sites in proteins, hepcidin affects their free metal ion pools and differentially impacts downstream processes and cell fate.

Short communication on the role of cellulosic fiber-based packaging in reduction of climate change impacts

2021 ◽  
Vol 254 ◽  
pp. 117248
Author(s):  
Urs Schenker ◽  
Julia Chardot ◽  
Karim Missoum ◽  
Alexey Vishtal ◽  
Julien Bras
Keyword(s):  
Climate Change ◽  
Short Communication ◽  
Climate Change Impacts ◽  
Cellulosic Fiber

Biosorption of Cadmium onto Pseudomonas fluorescens: Application of Isotherm and Kinetic Models

2010 ◽  
Vol 171-172 ◽  
pp. 49-52 ◽  
Author(s):  
Chang Li Yu ◽  
Zhi Peng Lu ◽  
Fa Zhi Ge ◽  
Er Li Zhao
Keyword(s):  
Pseudomonas Fluorescens ◽  
Functional Groups ◽  
Metal Ion ◽  
Freundlich Isotherm ◽  
Industrial Effluents ◽  
Rate Equations ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Kinetics Of Adsorption ◽  
Isotherm And Kinetic Models

The present study was undertaken to evaluate the feasibility of Pseudomonas fluorescens biomass for the removal of cadmium ions from aqueous solutions. Batch experiments were performed to study the adsorption of cadmium on pH, Pseudomonas fluorescens biomass adsorbent with respect to initial Cd(II) concentration, contact time and biomass dose. The experimental data were modeled by Langmuir and Freundlich isotherm models. Langmuir model resulted in the best fit of the adsorption data. The maximum adsorption capacity for Cd(II) was 66.25 mg/g (pH 5.0 and 5 g/L biomass dose). Kinetics of adsorption followed second-order rate equations. The FTIR results of Pseudomonas fluorescens biomass showed that biomass has different functional groups and these functional groups are able to react with metal ion in aqueous solution. The results of the present study suggest that Pseudomonas fluorescens biomass can be used beneficially in treating industrial effluents containing heavy metal ions.

scholarly journals Catalytic and structural role of the metal ion in dUTP pyrophosphatase

2003 ◽  
Vol 100 (10) ◽  
pp. 5670-5675 ◽  
Author(s):  
D. Mustafi ◽  
A. Bekesi ◽  
B. G. Vertessy ◽  
M. W. Makinen
Keyword(s):  
Metal Ion ◽  
Structural Role

Thermally Induced Electron Transfer in a CsCoFe Prussian Blue Derivative: The Specific Role of the Alkali-Metal Ion

2004 ◽  
Vol 116 (28) ◽  
pp. 3814-3817 ◽  
Author(s):  
Anne Bleuzen ◽  
Virginie Escax ◽  
Alban Ferrier ◽  
Françoise Villain ◽  
Michel Verdaguer ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Alkali Metal ◽  
Prussian Blue ◽  
Metal Ion ◽  
Specific Role ◽  
Alkali Metal Ion ◽  
Thermally Induced

Activités cholinestérasiques dans le foie de Poulet Rôle de l'endoderme dans l'apparition d'activités cholinestérasiques dans la composante mésenchymateuse du tissu hépatique

Development ◽  
1971 ◽  
Vol 26 (3) ◽  
pp. 481-495
Author(s):  
Par Elisabeth Houssaint ◽  
Nicole Le Douarin
Keyword(s):  
Endothelial Cells ◽  
Chick Embryo ◽  
Cholinesterase Activity ◽  
Enzymic Activity ◽  
The Body ◽  
Hepatic Tissue ◽  
Experimental Procedure ◽  
Septum Transversum ◽  
Cholinesterase Activities

Cholinesterases in the chick liver. The role of the endoderm in the appearance of the activity of cholinesterases in the hepatic mesenchyme The histochemical method of Koelle & Friedenwald (1949), as modified by Gerebtzoff (1953), has been used to investigate the distribution of cholinesterases in the chick embryonic and adult liver. Non-specific cholinesterases and, in a lower proportion acetylcholinesterase, have been detected in the endothelial cells of blood sinusoids of both adult and embryonic hepatic tissue. The hepatocytes do not show any cholinesterase activity. Cholinesterases appear precociously in the liver mesenchyme, since they already occur in the septum transversum of the 3-day-old chick embryo. An experimental procedure preventing the invasion of the hepatic mesenchymal Anlage by the endodermic cords has been used. The experimentally isolated hepatic mesenchyme shows an important cholinesterase activity; therefore this activity does not depend on the presence of the hepatocytes. The grafting of the determined hepatic endodern in the somatopleura of the 3-day-old chick embryo results in the development of hepatic tissue in the body wall. In this experimentally produced liver, cholinesterase activities are present in the endothelial cells which have arisen from somatopleura mesenchymal cells, though normally somatopleural mesenchyme does not possess these enzymes. The role of the endoderm in the appearance of this enzymic activity in the somatopleural mesenchyme is discussed.

Why do zeolites induce an unprecedented electronic state on exchanged metal ions?

2017 ◽  
Vol 19 (36) ◽  
pp. 25105-25114 ◽  
Author(s):  
Akira Oda ◽  
Takahiro Ohkubo ◽  
Takashi Yumura ◽  
Hisayoshi Kobayashi ◽  
Yasushige Kuroda
Keyword(s):  
Metal Ions ◽  
Electronic State ◽  
Base Metal ◽  
Metal Ion ◽  
High Efficiency ◽  
Lewis Base ◽  
Mfi Zeolite ◽  
Adsorption Processes ◽  
Exact Position

Understanding the exact position and the detailed role of the Al array in zeolites is essential for elucidating the origin of unique properties and for designing zeolite materials with high efficiency in catalytic and adsorption processes. In this work, we advanced pivotal roles of Lewis base–metal ion bifunctionality caused by Al atoms arrayed circumferentially in the MFI-zeolite pores.

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