Calcium amendment improved the performance of fragrant rice and reduced metal uptake under cadmium toxicity

The underlying mechanism and cellular responses of bacteria against toxic cadmium ions is still not fully understood. Herein,Escherichia coliTG1 expressing hexahistidine-green fluorescent protein (His6GFP) and cells expressing polyhistidine-fused to the outer membrane protein A (His-OmpA) were applied as models to investigate roles of cytoplasmic metal complexation and metal chelation at the surface membrane, respectively, upon exposure to cadmium stress. Two-dimensional gel electrophoresis (2-DE) and two-dimensional difference in gel electrophoresis (2D-DIGE) in conjunction with mass spectrometry-based protein identification had successfully revealed the low level expression of antioxidative enzymes and stress-responsive proteins such as manganese-superoxide dismutase (MnSOD; +1.65 fold), alkyl hydroperoxide reductase subunit C (AhpC; +1.03 fold) and DNA starvation/stationary phase protection protein (Dps; −1.02 fold) in cells expressing His6GFP in the presence of 0.2 mM cadmium ions. By contrarily, cadmium exposure led to the up-regulation of MnSOD of up to +7.20 and +3.08 fold in TG1-carrying pUC19 control plasmid and TG1 expressing native GFP, respectively, for defensive purposes against Cd-induced oxidative cell damage. Our findings strongly support the idea that complex formation between cadmium ions and His6GFP could prevent reactive oxygen species (ROS) caused by interaction between Cd2+and electron transport chain. This coincided with the evidence that cells expressing His6GFP could maintain their growth pattern in a similar fashion as that of the control cells even in the presence of harmful cadmium. Interestingly, overexpression of either OmpA or His-OmpA inE. colicells has also been proven to confer protection against cadmium toxicity as comparable to that observed in cells expressing His6GFP. Blockage of metal uptake as a consequence of anchored polyhistidine residues on surface membrane limited certain amount of cadmium ions in which some portion could pass through and exert their toxic effects to cells as observed by the increased expression of MnSOD of up to +9.91 and +3.31 fold in case of TG1 expressing only OmpA and His-OmpA, respectively. Plausible mechanisms of cellular responses and protein mapping in the presence of cadmium ions were discussed. Taken together, we propose that the intracellular complexation of cadmium ions by metal-binding regions provides more efficiency to cope with cadmium stress than the blockage of metal uptake at the surface membrane. Such findings provide insights into the molecular mechanism and cellular adaptation against cadmium toxicity in bacteria.

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ZnO Nanoparticle-based Seed Priming Modulates Early Growth and Enhances Physio-biochemical and Metabolic Profiles of Fragrant Rice Against Cadmium Toxicity

10.21203/rs.3.rs-113495/v1 ◽

2020 ◽

Author(s):

Yuzhan Li ◽

Luxin Liang ◽

Wu Li ◽

Umair Ashraf ◽

Lin Ma ◽

...

Keyword(s):

Heavy Metals ◽

Seed Germination ◽

Cadmium Toxicity ◽

Seed Priming ◽

Zno Nanoparticle ◽

Cd Stress ◽

Fresh Weight ◽

Toxic Heavy Metals ◽

Zno Nps ◽

Fragrant Rice

Abstract Background: Cadmium (Cd) is among the most toxic heavy metals that severely affects crop growth, and in this purview numerous recent research initiatives have focused on the application of nanoparticles (NPs) to negate the toxic effects of heavy metals such as Cd. Method: In the present study, the seeds of two fragrant rice cultivars, namely Yuxiangyouzhan and Xiangyaxiangzhan, were grown after exposure to four ZnO NPs treatment (0, 25, 50, and 100 mg L-1), with or without the presence of Cd (100 mg L-1). Result: The results revealed that priming seeds with ZnO NPs had no significant effect on the seed germination (p > 0.05) however, it substantially improved the seedling growth and other related physiological attributes under the Cd stress. The mean fresh weight of the shoot, and whole seedling increased after ZnO NPs treatment by 16.92%-27.88% and 12.82-33.58%, respectively. The fresh weight of root, length of the shoot, and the root increased after ZnO NPs treatment. Moreover, remarkable changes in the physiological response of seedlings under ZnO NPs treatment were detected. The metabolomic analysis was performed to discern the underlying regulation of the metabolisms after ZnO NPs treatment for seedlings under Cd stress. Conclusion: Our findings provide new insight into the influence of ZnO NPs on seed germination, and the growth of crop plants, and may find potential applications in developing crop resilience in Cd laden agricultural lands.

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Methyl jasmonate alleviates cadmium toxicity in Solanum nigrum by regulating metal uptake and antioxidative capacity

Biologia Plantarum ◽

10.1007/s10535-015-0491-4 ◽

2015 ◽

Vol 59 (2) ◽

pp. 373-381 ◽

Cited By ~ 34

Author(s):

Z. Yan ◽

W. Zhang ◽

J. Chen ◽

X. Li

Keyword(s):

Methyl Jasmonate ◽

Metal Uptake ◽

Cadmium Toxicity ◽

Solanum Nigrum ◽

Antioxidative Capacity

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Trace metal uptake in cockles Anadara trapezium from Lake Macquarie, New South Wales

Marine Ecology Progress Series ◽

10.3354/meps095135 ◽

1993 ◽

Vol 95 ◽

pp. 135-142

Author(s):

P Scanes

Keyword(s):

Trace Metal ◽

Metal Uptake ◽

New South ◽

New South Wales ◽

South Wales

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Determination of Some Heavy Metals in Milk of Cow Grazing At Selected Areas, of Kaduna Metropolis

International Journal of Advanced Research in Computer Science and Software Engineering ◽

10.23956/ijarcsse/v7i6/01617 ◽

2017 ◽

Vol 7 (7) ◽

pp. 341 ◽

Cited By ~ 1

Author(s):

Mahmud Mohammed Imam ◽

Zahra Muhammad ◽

Amina Zakari

Keyword(s):

Heavy Metals ◽

Cadmium Toxicity ◽

Research Work ◽

The Body ◽

Cow Milk ◽

Scientific Model ◽

Potential Health ◽

Milk Samples ◽

Lead And Cadmium ◽

Digestion Technique

In this research work the concentration of zinc, copper, lead, chromium, cadmium, and nickel in cow milk samples obtained from four different grazing areas (kakuri, kudendan, malali, kawo) of Kaduna metropolis. The samples were digested by wet digestion technique .The trace element were determined using bulk scientific model VPG 210 model Atomic Absorption Spectrophotometer (AAS).. The concentration of the determined heavy metal were The result revealed that Cr, Ni and Cd were not detected in milk samples from Kawo, Malali and Kudendan whereas lead (Pb) is detected in all samples and found to be above the stipulated limits of recommended dietary allowance (NRC,1989) given as 0.02mg/day. Cu and Zn are essential elements needed by the body for proper metabolism and as such their deficiency or excess is very dangerous for human health. However, they were found in all samples and are within the recommended limits while Cd (2.13 – 3.15 mg/kg) in milk samples from Kakuri was found to be above such limit (0.5mg/day). Cow milk samples analyzed for heavy metals in this research work pose a threat of lead and cadmium toxicity due to their exposure to direct sources of air, water and plants in these grazing areas, thereby, resulting to a potential health risk to the consumers.

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