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Humans are estimated to consume several grams per week of nanoplastics (NPs) through exposure to a variety of contamination sources. Nonetheless, the effects of these polymeric particles on living systems are still mostly unknown. Here, by means of CD, NMR and TEM analyses, we describe at an atomic resolution the interaction of ubiquitin with polystyrene NPs (PS-NPs), showing how a hard protein corona is formed. Moreover, we report that in human HeLa cells exposure to PS-NPs leads to a sensible reduction of ubiquitination. Our study overall indicates that PS-NPs cause significant structural effects on ubiquitin, thereby influencing one of the key metabolic processes at the base of cell viability.

This book addresses a broad range of issues concerning microplastic pollution, including microplastic pollution in various environments (freshwater, marine, air and soil); the sources, fate and effects of microplastics; detection systems for microplastic pollution monitoring; green approaches for the synthesis of environmentally friendly polymers; recovery and recycling of marine plastics; wastewater treatment plants as a microplastic entrance route; nanoplastics as emerging pollutants; degradation of plastics in the marine environment; impacts of microplastics on marine life; microplastics: from marine pollution to the human food chain; mitigation of microplastic impacts and innovative solutions; sampling, extraction, purification and identification approaches for microplastics; adsorption and transport of pollutants on and in microplastics; and lastly, the socio-economic and environmental impacts: assessment and risk analysis

Since 1950s, the introduction of plastic materials in the global markets has led to important technological advances and brought many advantages in our life. Synthetic polymers are durable, lightweight, moldable and for these properties widely used in different sectors. However, the main disadvantage of the worldwide diffusion and the increased demand of plastics is represented by their disposal, which occurs too often in an uncontrolled way and ending up in the natural environment. Combining this aspect with the durability of plastics, the consequence is the problem of plastic pollution. In recent years, great attention and concern has been arising on the presence and consequent impact of plastics in marine environments. Plastic litter has been reported to interact by entanglement or ingestion with several species, from seabirds to crustaceans, fish, turtles and even big marine mammals. The problem of plastic pollution have become even more worrisome and challenging, when it was discovered that it involves not only the macro scale, but also the micro dimensions. Microplastics, plastic particles smaller than 5 mm, have been found in seas and oceans, rivers, lakes and remote places like the artic and the deep sea. These particles can be ingested and interact with marine fauna and potentially can leach toxic compounds or accumulate pollutants already present in the water. Currently, it is important to provide more researches and data on the impact of microplastics on the environment, particularly to better understand the possible consequences on humans.

During the last five years, research activities have been focused on the study of structure-properties relationship of synthetic fabrics to determine the main factors that affect microplastic release. Nowadays, microplastics released from synthetic fabrics are considered emerging pollutants with a wide distribution in the environment. These enter the environment as primary microplastics, generated during the washing process, in the wastewater and, generated by fabric abrasion, in the atmospheric fallout. Several analytical procedures have been set up to evaluate the extent of microfibres released from textiles during washings at lab scale [1], during laundering at real scale [2,3], and finally during textile wearing. Their application has allowed the determination of the effective contribution of the washing process to microplastic pollution as well as the identification of specific trends in microplastic release as a function of textile nature, structure and geometry, laundering detergents and additives, washing conditions and parameters. In order to reduce the impact of microplastics released from textiles, several mitigation strategies have been designed, by approaching this problem at its sources such as the fabric surface and the washing machine. In this respect, new finishing treatments were developed, based on the usage of natural and biodegradable polymers. The formation of a uniform and thin coating layer on fabric surface was proved to be effective in reducing more than 80% the amount of microfibres released during washing tests [4,5]. In addition, new filtration systems for laundry machine were designed and their effectiveness in reducing the amount of microfibres in wastewater was demonstrated.

Membrane fusion/fission is a highly dynamic and conserved process that responds to intra- and extracellular signals. Whereas the molecular machineries involved in membrane fusion/fission have been dissected, regulation of membrane dynamics remains poorly understood. The lysosomal vacuole of budding yeast (Saccharomyces cerevisiae) has served as a seminal model in studies of membrane dynamics. We have previously established that yeast ENV7 encodes an ortholog of STK16-related kinases that localizes to the vacuolar membrane and downregulates vacuolar membrane fusion. Additionally, we have previously reported that Env7 phosphorylation in vivo depends on YCK3, a gene that encodes a vacuolar membrane casein kinase I (CKI) homolog that nonredundantly functions in fusion regulation. Here, we report that Env7 physically interacts with and is directly phosphorylated by Yck3. We also establish that Env7 vacuole fusion/fission regulation and vacuolar localization are mediated through its Yck3-dependent phosphorylation. Through extensive site-directed mutagenesis, we map phosphorylation to the Env7 C terminus and confirm that Ser-331 is a primary and preferred phosphorylation site. Phospho-deficient Env7 mutants were defective in negative regulation of membrane fusion, increasing the number of prominent vacuoles, whereas a phosphomimetic substitution at Ser-331 increased the number of fragmented vacuoles. Bioinformatics approaches confirmed that Env7 Ser-331 is within a motif that is highly conserved in STK16-related kinases and that it also anchors an SXXS CKI phosphorylation motif ((328)SRFS(331)). This study represents the first report on the regulatory mechanism of an STK16-related kinase. It also points to regulation of vacuolar membrane dynamics via a novel Yck3–Env7 kinase cascade.

Lipid droplets (LDs) have emerged as dynamic and interactive organelles with important roles in lipid metabolism and membrane biogenesis. Here, we report that Saccharomyces cerevisiae Env9 is a novel conserved oxidoreductase involved in LD morphology. Microscopic and biochemical studies confirm localization of tagged Env9 to LDs and implicate its C-terminal hydrophobic domain (aa241-265) in its membrane association and stability. Confocal studies reveal a role for Env9 in LD morphology. Env9 positively affects both formation of large LDs upon overexpression and LD proliferation under poor carbon source. In silico bioinformatic and modeling approaches establish that ENV9 is a widely conserved member of the short-chain dehydrogenase (SDR) superfamily. Bayesian phylogenetic studies strongly support ENV9 as an ortholog of human SDR retinol dehydrogenase 12 (RDH12). Dehydrogenase activity of Env9 was confirmed by in vitro oxidoreductase assays. RDH12 mutations have been linked to Leber Congenital Amaurosis. Similar site-directed point mutations in the predicted Env9 oxidoreductase active site (N146L) or cofactor-binding site (G23-24A) abolished its reductase activity in vitro, consistent with those reported in other retinol dehydrogenases. The same residues were essential for affecting LD size and number in vivo. Taken together, our results implicate oxidoreductase activity of Env9 in its cellular role in LD morphology.

Name of the deliverable: Pilot washing experiences Number of the associated action: B4 Project: LIFE13 ENV/IT/001069 Mermaids

Name of the deliverable: Report on additives for detergents and washing liquor in lowering microplastics release Number of the associated action: B2 Project LIFE13 ENV/IT/001069 Mermaids

Handbook for zero microplastics from textiles and laundry Good practice guidelines for the textile industry

Name of the deliverable: Report on the monitoring of the project actions. Number of the associated action: C1 LIFE13 ENV/IT/001069 MERMAIDS

Name of the deliverable: Policy recommendations based on actions A and B Number of the associated action: B6 Project: LIFE13 ENV/IT/001069 Mermaids

Name of the deliverable: Environmental Baseline Scenario Number of the associated action: C2 LIFE13 ENV/IT/001069 MERMAIDS

Name of the deliverable: Report on the influence of commercial textile finishing, fabrics geometry and washing conditions on microplastics release Number of the associated action: A2 Project LIFE13 ENV/IT/001069 MERMAIDS

Analysis of the regulatory framework and voluntary schemes concerning microplastics release by laundry processes Number of the associated action: A3 Project LIFE13 ENV/IT/001069 Mermaids

Name of the deliverable: Optimized washing recommendations in real conditions Number of the associated action: B3 Project LIFE13 ENV/IT/001069 Mermaids

Name of the deliverable: Social and economical report Number of the associated action: C3 LIFE13 ENV/IT/001069 Mermaids

Name of the deliverable: Report on the influence of commercial laundry agents and washing conditions on microplastics release reduction by use of commercial detergents, additives and changing laundering conditions Number of the associated action: A2 Project LIFE13 ENV/IT/001069 MERMAIDS

Name of the deliverable: LCA report Number of the associated action: C2 LIFE13 ENV/IT/001069 MERMAIDS

The influence of crystal polymorphism on the thermal properties of poly( l -lactic acid) (PLLA) is discussed in this contribution. Crystallization of PLLA at high temperatures yields the stable α form, whereas at low temperatures the metastable α′ modification develops, which is characterized by slightly larger lattice dimensions compared to the α counterpart, and by some degree of conformational disorder. Quantitative analysis with conventional and temperature-modulated calorimetry revealed a three-phase structure of PLLA composed of a crystal phase and two amorphous fractions with different mobility, for all the analyzed thermal histories. A higher coupling of the amorphous chain segments with the crystal phase was found in the presence of α crystals, probably due to the slightly larger lattice dimensions and the looser arrangements of PLLA chains in the α′ structure. Some peculiarities in the thermal behavior were rationalized, like an unusual frequency-dependence of the reversing apparent heat capacity upon the solid–solid transition from the α′ to the α crystals. Devitrification of the rigid amorphous segments seems also to be differently affected by the coupled crystal structure for the two analyzed crystal modifications of PLLA.

Isothermal and non-isothermal crystallization kinetics of poly(L-lactic acid)/poly(butylene terephthalate) (PLLA/PBT) blends containing PLLA as major component is detailed in this contribution. PLLA and PBT are not miscible, but compatibility of the polymer pair is ensured by interactions between the functional groups of the two polyesters, established upon melt mixing. Crystal polymorphism of the two polyesters is not influenced by blending, as probed by wide-angle X-ray analysis. The addition of PLLA does not affect the temperature range of crystallization kinetics of PBT, nor the crystallinity level attained when the blends are cooled from the melt at constant rate. Conversely, PBT favors crystallization of the biodegradable polyester. The addition of PBT results in an anticipated onset of crystallization of PLLA during cooling at a fixed rate, with a sizeable enhancement of the crystal fraction. Isothermal crystallization analysis confirmed the faster crystallization rate of PLLA in the presence of PBT.

Membrane fusion depends on conserved components and is responsible for organelle biogenesis and vesicular trafficking. Yeast vacuoles are dynamic structures analogous to mammalian lysosomes. We report here that yeast Env7 is a novel palmitoylated protein kinase ortholog that negatively regulates vacuolar membrane fusion. Microscopic and biochemical studies confirmed the localization of tagged Env7 at the vacuolar membrane and implicated membrane association via the palmitoylation of its N-terminal Cys13 to -15. In vitro kinase assays established Env7 as a protein kinase. Site-directed mutagenesis of the Env7 alanine-proline-glutamic acid (APE) motif Glu269 to alanine results in an unstable kinase-dead allele that is stabilized and redistributed to the detergent-resistant fraction by interruption of the proteasome system in vivo. Palmitoylation-deficient Env7C13-15S is also kinase dead and mislocalizes to the cytoplasm. Microscopy studies established that env7Δ is defective in maintaining fragmented vacuoles during hyperosmotic response and in buds. ENV7 function is not redundant with a similar role of vacuolar membrane kinase Yck3, as the two do not share a substrate, and ENV7 is not a suppressor of yck3Δ. Bayesian phylogenetic analyses strongly support ENV7 as an ortholog of the gene encoding human STK16, a Golgi apparatus protein kinase with undefined function. We propose that Env7 function in fusion/fission dynamics may be conserved within the endomembrane system.

With the aim at formulating new materials with biocidal activity a silver/polyurethane nanocomposite was prepared by in situ reduction of silver nitrate in a solution consisting of a commercial poly(carbonate urethane) dissolved in DMF, DMF acting as both polymer solvent and reducing agent. Bacteriological tests were performed with mesophilic, Gram-positive and Gram-negative bacteria, in liquid media and on solid agar plates supplemented with nanocomposite film samples. The growth inhibition achieved proved that the material set up was an effective bactericide. Release tests against E. coil were also carried out showing that the silver/polyurethane achieved exerts its biocidal activity through slow release of silver nanoparticles. Two different mechanisms reported in literature were invoked to account for the biocidal action of the silver nanoparticles released.

With the aim at formulating new materials with biocidal activity a silver/polyurethane nanocomposite was prepared by in situ reduction of silver nitrate in a solution consisting of a commercial poly(carbonate urethane) dissolved in DMF, DMF acting as both polymer solvent and reducing agent. Bacteriological tests were performed with mesophilic, Gram-positive and Gram-negative bacteria, in liquid media and on solid agar plates supplemented with nanocomposite film samples. The growth inhibition achieved proved that the material set up was an effective bactericide. Release tests against E. coli were also carried out showing that the silver/polyurethane achieved exerts its biocidal activity through slow release of silver nanoparticles. Two different mechanisms reported in literature were invoked to account for the biocidal action of the silver nanoparticles released. Copyright © 2012 American Scientific Publishers All rights reserved.

Two different diisocyanates were investigated as co-monomers for in situ polymerisation of poly(urethane-urea) into Neapolitan yellow tuff for conservation and restoration purpose. The obtained copolymers were characterised by means of FTIR spectroscopy, whereas the protective and consolidating efficiency of the performed treatments was evaluated through water capillary absorption, water vapour permeability and abrasion resistance measurements. The distribution and the penetration depth of the synthesized copolymer were also analysed applying micro-FTIR. The morphology of treated tuff was investigated by SEM. It was shown that comparatively higher protective and consolidating properties are achieved by using 1,6-diisocyanatohexane as monomer for in situ polymerisation.