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Organic-based amendments are promising, eco-friendly solutions among soil requalification strategies. In this context, the current study explored the application of compost to Technosols (2 kg m-2) to improve soil quality, making the substrate suitable for plant growth. Changes in soil quality have been assessed before compost addition (time zero, T0) and plant transplanting and at 2, 4 and 11 months (T2, T4, and T11) after plant establishment. To test the soil suitability for plant growth, we monitored (at T2, T4, and T11) structural and functional ecological traits in the herbaceous spontaneous species Malva sylvestris L. and in transplanted Mediterranean sclerophyllous Phillyrea angustifolia L., and Quercus ilex L., often used in the urban greening, also considering plant and soil relationships. Our study demonstrated that compost increased soil nutrients availability over time, favoring M. sylvestris physiological performance in long-lasting, compared to sclerophyllous, since the beginning of the application. M. sylvestris exhibited high photosynthetic efficiency and carbon investment in photosynthetic tissues (higher leaf area and lower leaf mass per area) on compost-enriched soil. On the other hand, P. angustifolia and Q. ilex, even if they did not benefit from compost addition for photosynthetic efficiency, after 11 months, maintained higher leaf water content despite limited soil water availability. These results encourage the use of compost in ameliorating the quality of Technosols for urban greening, also evidencing that the species'choice is pivotal in obtaining benefits from plants and a period longer than one year is needed for sclerophyllous to see beneficial effects. [ABSTRACT FROM AUTHOR]

Rapidly evolving influenza A viruses (IAVs) and influenza B viruses (IBVs) are major causes of recurrent lower respiratory tract infections. Current influenza vaccines elicit antibodies predominantly to the highly variable head region of haemagglutinin and their effectiveness is limited by viral drift1 and suboptimal immune responses2. Here we describe a neuraminidase-targeting monoclonal antibody, FNI9, that potently inhibits the enzymatic activity of all group 1 and group 2 IAVs, as well as Victoria/2/87-like, Yamagata/16/88-like and ancestral IBVs. FNI9 broadly neutralizes seasonal IAVs and IBVs, including the immune-evading H3N2 strains bearing an N-glycan at position 245, and shows synergistic activity when combined with anti-haemagglutinin stem-directed antibodies. Structural analysis reveals that D107 in the FNI9 heavy chain complementarity-determinant region 3 mimics the interaction of the sialic acid carboxyl group with the three highly conserved arginine residues (R118, R292 and R371) of the neuraminidase catalytic site. FNI9 demonstrates potent prophylactic activity against lethal IAV and IBV infections in mice. The unprecedented breadth and potency of the FNI9 monoclonal antibody supports its development for the prevention of influenza illness by seasonal and pandemic viruses.The neuraminidase-targeting monoclonal antibody FNI9 potently inhibits the enzymatic activity of influenza A and B viruses via receptor mimicry. [ABSTRACT FROM AUTHOR]

Supramolecular polymers are composed of monomers that self-assemble non-covalently, generating distributions of monodimensional fibres in continuous communication with each other and with the surrounding solution. Fibres, exchanging molecular species, and external environment constitute a sole complex system, which intrinsic dynamics is hard to elucidate. Here we report coarse-grained molecular simulations that allow studying supramolecular polymers at the thermodynamic equilibrium, explicitly showing the complex nature of these systems, which are composed of exquisitely dynamic molecular entities. Detailed studies of molecular exchange provide insights into key factors controlling how assemblies communicate with each other, defining the equilibrium dynamics of the system. Using minimalistic and finer chemically relevant molecular models, we observe that a rich concerted complexity is intrinsic in such self-assembling systems. This offers a new dynamic and probabilistic (rather than structural) picture of supramolecular polymer systems, where the travelling molecular species continuously shape the assemblies that statistically emerge at the equilibrium. The dynamic structure of supramolecular polymers is challenging to determine both in experiments and in simulations. Here the authors use coarse-grained molecular models to provide a comprehensive analysis of the molecular communication in these complex molecular systems. [ABSTRACT FROM AUTHOR]

The recently emerged SARS-CoV-2 Omicron variant encodes 37 amino acid substitutions in the spike protein, 15 of which are in the receptor-binding domain (RBD), thereby raising concerns about the effectiveness of available vaccines and antibody-based therapeutics. Here we show that the Omicron RBD binds to human ACE2 with enhanced affinity, relative to the Wuhan-Hu-1 RBD, and binds to mouse ACE2. Marked reductions in neutralizing activity were observed against Omicron compared to the ancestral pseudovirus in plasma from convalescent individuals and from individuals who had been vaccinated against SARS-CoV-2, but this loss was less pronounced after a third dose of vaccine. Most monoclonal antibodies that are directed against the receptor-binding motif lost in vitro neutralizing activity against Omicron, with only 3 out of 29 monoclonal antibodies retaining unaltered potency, including the ACE2-mimicking S2K146 antibody1. Furthermore, a fraction of broadly neutralizing sarbecovirus monoclonal antibodies neutralized Omicron through recognition of antigenic sites outside the receptor-binding motif, including sotrovimab2, S2X2593 and S2H974. The magnitude of Omicron-mediated immune evasion marks a major antigenic shift in SARS-CoV-2. Broadly neutralizing monoclonal antibodies that recognize RBD epitopes that are conserved among SARS-CoV-2 variants and other sarbecoviruses may prove key to controlling the ongoing pandemic and future zoonotic spillovers.Pseudovirus assays and surface plasmon resonance show that the Omicron receptor-binding domain binds to human ACE2 with increased affinity relative to the ancestral virus, and that most neutralizing antibodies are considerably less potent against Omicron. [ABSTRACT FROM AUTHOR]

The recent emergence of SARS-CoV-2 variants of concern1–10 and the recurrent spillovers of coronaviruses11,12 into the human population highlight the need for broadly neutralizing antibodies that are not affected by the ongoing antigenic drift and that can prevent or treat future zoonotic infections. Here we describe a human monoclonal antibody designated S2X259, which recognizes a highly conserved cryptic epitope of the receptor-binding domain and cross-reacts with spikes from all clades of sarbecovirus. S2X259 broadly neutralizes spike-mediated cell entry of SARS-CoV-2, including variants of concern (B.1.1.7, B.1.351, P.1, and B.1.427/B.1.429), as well as a wide spectrum of human and potentially zoonotic sarbecoviruses through inhibition of angiotensin-converting enzyme 2 (ACE2) binding to the receptor-binding domain. Furthermore, deep-mutational scanning and in vitro escape selection experiments demonstrate that S2X259 possesses an escape profile that is limited to a single substitution, G504D. We show that prophylactic and therapeutic administration of S2X259 protects Syrian hamsters (Mesocricetus auratus) against challenge with the prototypic SARS-CoV-2 and the B.1.351 variant of concern, which suggests that this monoclonal antibody is a promising candidate for the prevention and treatment of emergent variants and zoonotic infections. Our data reveal a key antigenic site that is targeted by broadly neutralizing antibodies and will guide the design of vaccines that are effective against all sarbecoviruses.The human monoclonal antibody S2X259 cross-reacts with spike proteins from all clades of sarbecovirus, and provides prophylactic and therapeutic protection in vivo against parental SARS-CoV-2 and emerging variants of concern. [ABSTRACT FROM AUTHOR]

An ideal therapeutic anti-SARS-CoV-2 antibody would resist viral escape1–3, have activity against diverse sarbecoviruses4–7, and be highly protective through viral neutralization8–11 and effector functions12,13. Understanding how these properties relate to each other and vary across epitopes would aid the development of therapeutic antibodies and guide vaccine design. Here we comprehensively characterize escape, breadth and potency across a panel of SARS-CoV-2 antibodies targeting the receptor-binding domain (RBD). Despite a trade-off between in vitro neutralization potency and breadth of sarbecovirus binding, we identify neutralizing antibodies with exceptional sarbecovirus breadth and a corresponding resistance to SARS-CoV-2 escape. One of these antibodies, S2H97, binds with high affinity across all sarbecovirus clades to a cryptic epitope and prophylactically protects hamsters from viral challenge. Antibodies that target the angiotensin-converting enzyme 2 (ACE2) receptor-binding motif (RBM) typically have poor breadth and are readily escaped by mutations despite high neutralization potency. Nevertheless, we also characterize a potent RBM antibody (S2E128) with breadth across sarbecoviruses related to SARS-CoV-2 and a high barrier to viral escape. These data highlight principles underlying variation in escape, breadth and potency among antibodies that target the RBD, and identify epitopes and features to prioritize for therapeutic development against the current and potential future pandemics.A survey of SARS-CoV-2 RBD antibodies identifies those with activity against diverse SARS-CoV-2 variants and SARS-related coronaviruses, highlighting epitopes and features to prioritize in antibody and vaccine development. [ABSTRACT FROM AUTHOR]

Aims: Data on the decomposition of fine roots are scarce for the Mediterranean basin. This work aims to compare chemical traits, decomposition rate, and temperature sensitivity (Q10) for root and leaf litter of 43 Mediterranean species. Methods: We carried out a two-years litterbag decomposition experiment using 43 fine roots litter and leaf litter types incubated in laboratory conditions at three different temperatures, i.e. 4 °C, 14 °C, and 24 °C. Litter was characterized for carbon (C), nitrogen (N), lignin and cellulose concentration, C/N, and lignin/N ratios. Results: Fine root litter had lower N content but higher lignin concentration, lignin/N, and C/N ratios compared to leaf litter. The decay rate of fine root litter was slower than leaf litter. For both tissues, the decay rate was negatively associated with lignin concentration, lignin/N, and C/N ratios but positively with N concentration. Q10 was higher for fine root than leaf litter, with a positive correlation with lignin while negative with N concentration. Conclusions: Our findings demonstrate a higher Q10 accompanied by a slower decomposition rate of fine root litter compared to leaf litter in Mediterranean ecosystems. These results must be considered in modeling organic C at the ecosystem scale. [ABSTRACT FROM AUTHOR]

Transmission of SARS-CoV-2 is uncontrolled in many parts of the world; control is compounded in some areas by the higher transmission potential of the B.1.1.7 variant1, which has now been reported in 94 countries. It is unclear whether the response of the virus to vaccines against SARS-CoV-2 on the basis of the prototypic strain will be affected by the mutations found in B.1.1.7. Here we assess the immune responses of individuals after vaccination with the mRNA-based vaccine BNT162b22. We measured neutralizing antibody responses after the first and second immunizations using pseudoviruses that expressed the wild-type spike protein or a mutated spike protein that contained the eight amino acid changes found in the B.1.1.7 variant. The sera from individuals who received the vaccine exhibited a broad range of neutralizing titres against the wild-type pseudoviruses that were modestly reduced against the B.1.1.7 variant. This reduction was also evident in sera from some patients who had recovered from COVID-19. Decreased neutralization of the B.1.1.7 variant was also observed for monoclonal antibodies that target the N-terminal domain (9 out of 10) and the receptor-binding motif (5 out of 31), but not for monoclonal antibodies that recognize the receptor-binding domain that bind outside the receptor-binding motif. Introduction of the mutation that encodes the E484K substitution in the B.1.1.7 background to reflect a newly emerged variant of concern (VOC 202102/02) led to a more-substantial loss of neutralizing activity by vaccine-elicited antibodies and monoclonal antibodies (19 out of 31) compared with the loss of neutralizing activity conferred by the mutations in B.1.1.7 alone. The emergence of the E484K substitution in a B.1.1.7 background represents a threat to the efficacy of the BNT162b2 vaccine.Sera from vaccinated individuals and some monoclonal antibodies show a modest reduction in neutralizing activity against the B.1.1.7 variant of SARS-CoV-2; but the E484K substitution leads to a considerable loss of neutralizing activity. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a newly emerged coronavirus that is responsible for the current pandemic of coronavirus disease 2019 (COVID-19), which has resulted in more than 3.7 million infections and 260,000 deaths as of 6 May 20201,2. Vaccine and therapeutic discovery efforts are paramount to curb the pandemic spread of this zoonotic virus. The SARS-CoV-2 spike (S) glycoprotein promotes entry into host cells and is the main target of neutralizing antibodies. Here we describe several monoclonal antibodies that target the S glycoprotein of SARS-CoV-2, which we identified from memory B cells of an individual who was infected with severe acute respiratory syndrome coronavirus (SARS-CoV) in 2003. One antibody (named S309) potently neutralizes SARS-CoV-2 and SARS-CoV pseudoviruses as well as authentic SARS-CoV-2, by engaging the receptor-binding domain of the S glycoprotein. Using cryo-electron microscopy and binding assays, we show that S309 recognizes an epitope containing a glycan that is conserved within the Sarbecovirus subgenus, without competing with receptor attachment. Antibody cocktails that include S309 in combination with other antibodies that we identified further enhanced SARS-CoV-2 neutralization, and may limit the emergence of neutralization-escape mutants. These results pave the way for using S309 and antibody cocktails containing S309 for prophylaxis in individuals at a high risk of exposure or as a post-exposure therapy to limit or treat severe disease. The monoclonal antibody S309, identified from memory B cells of an individual infected with SARS-CoV in 2003, or antibody cocktails that contain this antibody potently neutralize SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Background and aim: Litter decomposition is of great concern as it plays a key role in regulating global carbon cycle and nutrient budgets, especially in tropical forests where it is very fast. Therefore, we studied the decomposition and subsequent changes in element concentrations and amounts of 11 tropical leaf litter.Methods: Fresh litters were characterized in terms of elemental, proximate features, as well as organic carbon compositions by 13C-NMR spectroscopy. Controlled litterbag decomposition was carried out for 180 days in the laboratory, bags were retrieved at three dates and analyzed for mass loss and concentration of nitrogen (N), potassium (K), sodium (Na), carbon (C), magnesium (Mg), manganese (Mn), iron (Fe), phosphorus (P), zinc (Zn), and percentage of ash, extractives, cellulose and lignin.Results: Terminalia arjuna showed highest mass loss, while the lowest was observed in Shorea robusta showing significant positive correlation with litter initial K, Mg, Fe and di-O-alkyl C, O-alkyl C, while significant negative correlation with Mn, lignin and Methoxyl C, Alkyl C. Trajectories shows that Fe, Mg, K, Mn, Zn and Na concentrations increased in most of the litter types, except Terminalia arjuna and Toona ciliata, where Fe, Mg, K concentrations decreased during decomposition. Surprisingly, in most of the species with the exception of Terminalia arjuna, N concentrations decreased at a faster rate than C concentrations, resulting in an increase in C/N ratios. Expectedly, lignin progressively increased, while cellulose decreased.Conclusions: Observed differences in decomposition rate and dynamics of chemical changes among litters were strongly affected by the litter type, decomposition time and their interactions. [ABSTRACT FROM AUTHOR]

Emerging multidrug-resistant bacteria are a challenge for modern medicine, but how these pathogens are so successful is not fully understood. Robust antibacterial vaccines have prevented and reduced resistance suggesting a pivotal role for immunity in deterring antibiotic resistance. Here, we show the increased prevalence of Klebsiella pneumoniae lipopolysaccharide O2 serotype strains in all major drug resistance groups correlating with a paucity of anti-O2 antibodies in human B cell repertoires. We identify human monoclonal antibodies to O-antigens that are highly protective in mouse models of infection, even against heavily encapsulated strains. These antibodies, including a rare anti-O2 specific antibody, synergistically protect against drug-resistant strains in adjunctive therapy with meropenem, a standard-of-care antibiotic, confirming the importance of immune assistance in antibiotic therapy. These findings support an antibody-based immunotherapeutic strategy even for highly resistant K. pneumoniae infections, and underscore the effect humoral immunity has on evolving drug resistance. [ABSTRACT FROM AUTHOR]

Background: The analysis of mineral elements composition was determined in three wild edible herbs (Cichorium intybus L., Sonchus asper L. and Borago oicinalis) collected in seven different sampling sites which were characterized by different pollution grade. The detection of mineral elements (Ca, K, Mg and Na), micronutrients (Cu, Fe, Li, Mn and Zn) and heavy metals (As, Cd, Hg, Ni and Pb) was performed. Results: The results obtained show that in most cases a direct relationship appeared between the amount of elements and the sampling sites. The highest concentrations of heavy metals were found in samples grown in polluted soils. These evaluations showed that contaminants in plants may reflect the environmental state in which they develop. Conclusion: The examined species are a good source of mineral elements and micronutrients, making them particularly adapt to integrate a well-balanced diet. The accumulation of heavy metals showed that contaminants in plants may reflect the environmental state in which they develop. Results showed high concentrations of heavy metals in samples taken in locations characterized by high human activity and in some samples from the local market, of which no one knows the collection area. [ABSTRACT FROM AUTHOR]

We studied late-stages decomposition of four types of coniferous needle and three types of deciduous leaf litter at two sites, one nutrient-poor boreal and one nutrient-rich temperate. The late stage was identified by that reached by litters at the onset of net loss of lignin mass, i.e. at about 1 year after the incubation when the highest amount of lignin had been detected; the study extended over the following 2 year period. Decomposition rates were significantly lower at the boreal than at the temperate site and did not differ between needle litter and leaf litter. In the boreal forest: (1) mass-loss was positively correlated with N and Mn release, (2) Mn concentration at the start of the late stage was positively correlated with lignin decay, (3) Ca concentration was negatively correlated to litter mass loss and lignin decay. In the temperate forest neither lignin, N, Mn, and Ca concentration at the start of the late stage, nor their dynamics were related to litter decomposition rates and lignin decay. In leaf litter mass-loss and lignin decay were positively correlated with N and Ca release and with Ca concentration. In needle litter mass-loss was positively correlated to Mn release and N concentration negatively with lignin decay. We concluded that Ca, N and Mn have different roles in controlling lignin decay depending on type of litter and site conditions. [ABSTRACT FROM AUTHOR]

Background and aim: Litter and soil characteristics influence the abundance and activities of decomposers and detritivores, thereby affecting C accumulation. The relationship between the chemical composition of soil organic matter and soil organisms is still unclear. The study aims to investigate how the quality and quantity of litter and soil organic matter influence C accumulation and the relationships between organic matter quality and bacteria, fungi and microarthropods in litter and soil.Litters and soils from 24 sites were analysed for the abiotic (pH, water content, total C and N content and the chemical composition of soluble C: carbohydrate, alkyl, O-alkyl, aromatic and carboxyl groups) and the biotic characteristics (bacterial and fungal abundances, urease and β-glucosidase, microbial respiration, microarthropod community).Litter had a high carbohydrate and low C contents, whereas soil had higher content of recalcitrant compounds (aromatic and carboxylic groups) and C. Whitin substrate types, higher C content was found in litter from shrubs and in soil under sclerophyllous evergreens. Bacterial abundances were lower in litter than in soil, whereas microbial respiration, enzymatic activities, microarthropod densities and predator abundances were higher in litter than in soil. Microbial abundances and activities were strongly related to total C and N concentrations in both litter and soil, while the microarthropod community was positively correlated with soluble C recalcitrant compounds in soil.Soils showed a high capacity for C accumulation due to the high content of recalcitrant compounds. In soil, the microarthropod community, more than bacteria and fungi, was positively correlated with the quality of organic matter.Materials and methods: Litter and soil characteristics influence the abundance and activities of decomposers and detritivores, thereby affecting C accumulation. The relationship between the chemical composition of soil organic matter and soil organisms is still unclear. The study aims to investigate how the quality and quantity of litter and soil organic matter influence C accumulation and the relationships between organic matter quality and bacteria, fungi and microarthropods in litter and soil.Litters and soils from 24 sites were analysed for the abiotic (pH, water content, total C and N content and the chemical composition of soluble C: carbohydrate, alkyl, O-alkyl, aromatic and carboxyl groups) and the biotic characteristics (bacterial and fungal abundances, urease and β-glucosidase, microbial respiration, microarthropod community).Litter had a high carbohydrate and low C contents, whereas soil had higher content of recalcitrant compounds (aromatic and carboxylic groups) and C. Whitin substrate types, higher C content was found in litter from shrubs and in soil under sclerophyllous evergreens. Bacterial abundances were lower in litter than in soil, whereas microbial respiration, enzymatic activities, microarthropod densities and predator abundances were higher in litter than in soil. Microbial abundances and activities were strongly related to total C and N concentrations in both litter and soil, while the microarthropod community was positively correlated with soluble C recalcitrant compounds in soil.Soils showed a high capacity for C accumulation due to the high content of recalcitrant compounds. In soil, the microarthropod community, more than bacteria and fungi, was positively correlated with the quality of organic matter.Results: Litter and soil characteristics influence the abundance and activities of decomposers and detritivores, thereby affecting C accumulation. The relationship between the chemical composition of soil organic matter and soil organisms is still unclear. The study aims to investigate how the quality and quantity of litter and soil organic matter influence C accumulation and the relationships between organic matter quality and bacteria, fungi and microarthropods in litter and soil.Litters and soils from 24 sites were analysed for the abiotic (pH, water content, total C and N content and the chemical composition of soluble C: carbohydrate, alkyl, O-alkyl, aromatic and carboxyl groups) and the biotic characteristics (bacterial and fungal abundances, urease and β-glucosidase, microbial respiration, microarthropod community).Litter had a high carbohydrate and low C contents, whereas soil had higher content of recalcitrant compounds (aromatic and carboxylic groups) and C. Whitin substrate types, higher C content was found in litter from shrubs and in soil under sclerophyllous evergreens. Bacterial abundances were lower in litter than in soil, whereas microbial respiration, enzymatic activities, microarthropod densities and predator abundances were higher in litter than in soil. Microbial abundances and activities were strongly related to total C and N concentrations in both litter and soil, while the microarthropod community was positively correlated with soluble C recalcitrant compounds in soil.Soils showed a high capacity for C accumulation due to the high content of recalcitrant compounds. In soil, the microarthropod community, more than bacteria and fungi, was positively correlated with the quality of organic matter.Conclusions: Litter and soil characteristics influence the abundance and activities of decomposers and detritivores, thereby affecting C accumulation. The relationship between the chemical composition of soil organic matter and soil organisms is still unclear. The study aims to investigate how the quality and quantity of litter and soil organic matter influence C accumulation and the relationships between organic matter quality and bacteria, fungi and microarthropods in litter and soil.Litters and soils from 24 sites were analysed for the abiotic (pH, water content, total C and N content and the chemical composition of soluble C: carbohydrate, alkyl, O-alkyl, aromatic and carboxyl groups) and the biotic characteristics (bacterial and fungal abundances, urease and β-glucosidase, microbial respiration, microarthropod community).Litter had a high carbohydrate and low C contents, whereas soil had higher content of recalcitrant compounds (aromatic and carboxylic groups) and C. Whitin substrate types, higher C content was found in litter from shrubs and in soil under sclerophyllous evergreens. Bacterial abundances were lower in litter than in soil, whereas microbial respiration, enzymatic activities, microarthropod densities and predator abundances were higher in litter than in soil. Microbial abundances and activities were strongly related to total C and N concentrations in both litter and soil, while the microarthropod community was positively correlated with soluble C recalcitrant compounds in soil.Soils showed a high capacity for C accumulation due to the high content of recalcitrant compounds. In soil, the microarthropod community, more than bacteria and fungi, was positively correlated with the quality of organic matter. [ABSTRACT FROM AUTHOR]