Seizing the digital identity and payments opportunity : national and EU experiences

This contribution was delivered on 5 May 2022 on the occasion of the hybrid 2022 edition of EUI State of the Union on ‘A Europe fit for the next generation?'EU Member States have adopted several initiatives to establish a legal and technical framework for digital identity. The European Commission has facilitated this development by offering guidance and promoting interoperable solutions through frameworks such as eIDAS and solutions developed within the European Interoperability Framework. At the same time, two years of COVID-19 pandemic have led at once to an acceleration of digital identity projects, and mounting concerns that widespread data collection and availability can lead to the risk of privacy violations, citizen profiling and mass surveillance. This session will explore the opportunities and challenges of emerging digital identity and digital payments, including the privacy, security concerns as well as the outstanding opportunities for inclusive growth, resilient and sustainable solutions for the society of the future. The discussion will also cover emerging attempts to develop joint European solutions for digital identity, including the recent joint declaration between the governments of Finland and Germany to support the progress of the proposed regulation on European digital identity, and to accelerate the development of joint European solutions based on digital identity

TUNING CYSTEINE REACTIVITY AND SULFENIC ACID STABILITY BY PROTEIN MICROENVIRONMENT IN GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASES OF ARABIDOPSIS THALIANA

Cysteines and H2O2 are fundamental players in redox signaling. Cysteine-thiol deprotonation favors the reaction with H2O2 that generates sulfenic acids with dual electrophilic/nucleophilic nature. The protein microenvironment surrounding the target cysteine is believed to control whether a sulfenic acid can be reversibly regulated by disulfide formation or irreversibly oxidized to sulfinates/sulfonates. Here, we present experimental oxidation kinetics and a QM/MM investigation to elucidate the reaction of H2O2 with glycolytic (AtGAPC1) and photosynthetic glyceraldehyde-3-phosphate dehydrogenase (AtGAPA) from Arabidopsis thaliana

Structural snapshots of nitrosoglutathione binding and reactivity underlying S-nitrosylation of photosynthetic GAPDH

S-nitrosylation is a redox post-translational modification widely recognized to play an important role in cellular signaling as it can modulate protein function and conformation. At the physiological level, nitrosoglutathione (GSNO) is considered the major physiological NO-releasing compound due to its ability to transfer the NO moiety to protein thiols but the structural determinants regulating its redox specificity are not fully elucidated. In this study, we employed photosynthetic glyceraldehyde-3-phosphate dehydrogenase from Chlamydomonas reinhardtii (CrGAPA) to investigate the molecular mechanisms underlying GSNO-dependent thiol oxidation. We first observed that GSNO causes reversible enzyme inhibition by inducing S-nitrosylation. While the cofactor NADP+ partially protects the enzyme from GSNO-mediated S-nitrosylation, protein inhibition is not observed in the presence of the substrate 1,3-bisphosphoglycerate, indicating that the S-nitrosylation of the catalytic Cys149 is responsible for CrGAPA inactivation. The crystal structures of CrGAPA in complex with NADP+ and NAD+ reveal a general structural similarity with other photosynthetic GAPDH. Starting from the 3D structure, we carried out molecular dynamics simulations to identify the protein residues involved in GSNO binding. The reaction mechanism of GSNO with CrGAPA Cys149 was investigated by quantum mechanical/molecular mechanical calculations, which permitted to disclose the relative contribution of protein residues in modulating the activation barrier of the trans-nitrosylation reaction. Based on our findings, we provide functional and structural insights into the response of CrGAPA to GSNO-dependent regulation, possibly expanding the mechanistic features to other protein cysteines susceptible to be oxidatively modified by GSNO