There is increasing interest in poplars and willows due to their biomass production and phytoremediation potential. They host two major types of mycorrhizal fungi that can substantially modulate the physiology of their hosts. In this study, the effects of endo-and ectomycorrhizal fungi on growth, physiological parameters, and heavy metals accumulation were studied in a pot experiment using Salix alba L. and Populus nigra L. The mycorrhizal fungi were inoculated separately and in combination to a soil substrate polluted by a mixture of heavy metals (mainly Cd, Pb, and Zn). Tree species differed in their mycorrhizal affinities, with poplar being colonized predominantly by Glomus intraradices and willow by Hebeloma mesophaeum. H. mesophaeum increased willow height and biomass, while G. intraradices decreased poplar height. The photosynthetic rate remained unchanged, and only minor changes were observed in the relative composition of photosynthetic pigments. Poplar photosynthetic rates and levels of photosynthetic pigments declined, while the epicuticular waxes in leaves increased toward the end of the experiment, irrespective of the inoculation. H. mesophaeum strongly reduced the accumulation of Cd and Fe in willow and poplar shoots, respectively. Our results support the use of selected mycorrhizal strains to tune phytoremediation outcomes in their plant hosts.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that affects both lower and upper motor neurons, leading to muscle atrophy, paralysis, and death caused by respiratory failure or infectious complications. Altered levels of homocysteine, cysteine, methionine, and glutamic acid have been observed in plasma of ALS patients. In this context, a method for determination of these potential biomarkers in plasma by capillary electrophoresis tandem mass spectrometry (CE-MS/MS) is proposed herein. Sample preparation was carefully investigated, since sulfur-containing amino acids may interact with plasma proteins. Owing to the non-thiol sulfur atom in methionine, it was necessary to split sample preparation into two methods: i) determination of homocysteine and cysteine as S-acetyl amino acids; ii) determination of glutamic acid and methionine. All amino acids were separated within 25min by CE-MS/MS using 5molL acetic acid as background electrolyte and 5mmolL acetic acid in 50% methanol/HO (v/v) as sheath liquid. The proposed CE-MS/MS method was validated, presenting RSD values below 6% and 11% for intra- and inter-day precision, respectively, for the middle concentration level within the linear range. The limits of detection ranged from 35 (homocysteine) to 268nmolL (glutamic acid). The validated method was applied to the analysis of plasma samples from a group of healthy individuals and patients with ALS, showing the potential of glutamic acid and homocysteine metabolites as biomarkers of ALS.

The discovery of potentially habitable conditions on Europa and Enceladus has led to an increased interest in searching for extant life in these locations (Chyba & Phillips, 2002;Porco et al., 2017). There is a consensus that multiple lines of evidence will be required to provide the extraordinary proof required to support any claims of the detection of extraterrestrial life (Hand et al., 2017). Among the possible lines of evidence, chemical biosignatures are considered key because of the way that life is expected to leave an imprint on chemical distributions, or by the presence of chemical complexity, that is difficult to explain via abiotic processes (Lovelock, 1965;McKay, 2004). Amino acids are among the targets that could be used to determine the presence of life beyond Earth (Neveu et al., 2018). Amino acids are the core of terrestrial life as the building blocks of proteins (Aerts et al., 2020), but are also found in meteorites, which indicates they do not have an Earth-specific origin (Glavin et al., 2010;Pizzarello et al., 2012). For this reason, the detection of one or more of the typical "meteoritic/abiotic" amino acids is not indicative of life, although detecting multiple more complex members of this compound class would suggest biotic processes. Fortunately, instead of relying only on the detection of certain amino acids, we can use their relative distributions to establish their biotic or abiotic origin. The first relative distribution is related to chiral forms of amino acids and expressed by enantiomeric excess. Life on Earth uses mostly left-handed amino acids, while abiotic samples contain mixtures of both chiral forms. The second distribution is related to the overall complexity of amino acids, as expressed by the ratio of each amino acid to the simplest one, glycine. While abiotic processes tend to produce simpler, easier to synthesize amino acids like glycine, amino acids produced biotically tend to be more complex as a requirement for protein functionality. Therefore, the determination of both enantiomeric excesses and relative abundances of amino acids could provide strong evidence of biogenicity (Creamer et al., 2017;McKay, 2004).A key challenge for amino acid analysis is their release from cells or proteins present in the sample. The gold standard method to achieve this in terrestrial laboratories is acid hydrolysis. While some alteration of amino acids can occur during this treatment (Kaiser & Benner, 2005;Pickering & Newton, 1990), it is overall a robust method for assessing amino acid distributions. However, implementing an extraction that requires 6 N HCl heated up to 110°C for 24 hr involves considerable developmental and operational risks which would significantly complicate

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