We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
The influence of polystyrene nanoparticles on enzyme clusters of fumarate, malate dehydrogenase and citrate synthase: a fractal analysis study
Summary
Polystyrene nanoparticles disrupted the activity of key energy metabolism enzymes in vitro and in mussels, with effects depending on particle concentration and the fractal geometry of enzyme clusters. This study suggests that nanoplastics can interfere with fundamental cellular energy processes in marine invertebrates.
In the context that plastic debris could degrade into smaller and smaller particles especially at the nanoscale, concerns about their ecotoxicological effects are raised. The purpose of this study was to determine the biophysical effects of neutral polystyrene nanoparticles (NPs) on the activity of fumarase-malate dehydrogenase (MDH)-citrate synthase (CS) cluster both in vitro and in mussels exposed to NPs. At first, commercial preparations of fumarase, MDH, CS were examined in the presence of NPs to determine changes in the fractal environment based on time dependence MDH and CS rates and changes in the spectral dimension (sD) of the cluster. In second part, these effects were also examined in mussels exposed to either polystyrene NPs or in mussels exposed to municipal effluents, which are suspected environmental sources of plastic NPs. The results showed that the presence of NPs decreased the time dependence of MDH rate and increased significantly the sD. A sD=0.55 of the in vitro reaction revealed a close organization of the enzyme cluster, which was equivalent to a random percolation cluster with 74% of space occupancy. The addition of 50 and 100 nm in the reaction media reduced the space occupancy to 50 and 33% respectively. Exposure of mussels to 50 nm NPs for 24h lead to increased levels of NPs in the digestive gland and revealed similar effects in the digestive gland subcellular fraction where the sD was increased from 1.25 to 1.48 at the highest concentration of 5 mg/L reducing the space occupancy of 35% compared to 46% in control mussels. Exposure of mussels to a municipal effluent for 3 months also lead to increased polystyrene-like NPs in the digestive gland and increased fumarase-MDH-CS activity and the sD even further to 23% space occupancy. In conclusion, polystyrene NPs have the capacity to increase the sD of the cluster decreasing the normal time-dependence of enzyme activity of the fumarase-MDH-CS cluster thereby maintaining energy metabolism for longer times which could deplete energy reserves.
Sign in to start a discussion.
More Papers Like This
Biophysical effects of polystyrene nanoparticles on Elliptio complanata mussels
Researchers exposed freshwater mussels to polystyrene nanoplastics and found that nanoparticles accumulated in the digestive gland and disrupted lipid metabolism, liquid crystal organization, and the normal oscillatory enzyme kinetics of energy-producing metabolic pathways, suggesting nanoplastics interfere with cellular energy homeostasis.
The pivotal role of bioenergetics in characterizing the hazards of polystyrene and polyethylene nanoparticles to bivalve health and development.
This study examined the metabolic toxicity of various nanoplastics on coastal marine invertebrates by measuring bioenergetic parameters, focusing on how plastic particles disrupt energy allocation in organisms adapted to coastal environments. Nanoplastic exposure impaired bioenergetics in marine organisms, indicating a physiologically significant stress response.
Functionalized polystyrene nanoplastic-induced energy homeostasis imbalance and the immunomodulation dysfunction of marine clams (Meretrix meretrix) at environmentally relevant concentrations
Functionalized polystyrene nanoplastics inhibited growth of marine clams (Meretrix meretrix) at environmentally relevant concentrations by disrupting energy homeostasis and immune function. The study demonstrated that surface functionalization of nanoplastics influences their toxicity to filter-feeding bivalves.
The pivotal role of bioenergetics in characterizing the hazards of polystyrene and polyethylene nanoparticles to bivalve health and development.
This study examined the metabolic toxicity of various nanoplastics on coastal marine organisms by focusing on bioenergetics, measuring how plastic particles disrupt the energy balance of animals adapted to coastal habitats. Nanoplastic exposure impaired energy metabolism, suggesting physiological stress that could affect survival and fitness in polluted coastal environments.
The Effect of Microplastics on the Bioenergetics of the Mussel Mytilus coruscus Assessed by Cellular Energy Allocation Approach
Researchers studied the effects of polystyrene microplastics on the energy budget of mussels using a cellular energy allocation approach. They found that higher concentrations of microplastics increased energy demands while depleting carbohydrate, lipid, and protein stores, with lipid and protein levels failing to fully recover even after the microplastics were removed.