Bcl-xL is an oncogene of which the survival functions are finely tuned by post-translational modifications (PTM). Within the Bcl-2 family of proteins, Bcl-xL shows unique eligibility to deamidation, a time-related spontaneous reaction. Deamidation is still a largely overlooked PTM due to a lack of easy techniques to monitor Asn→Asp/IsoAsp conversions or Glu→Gln conversions. Being able to detect PTMs is essential to achieve a comprehensive description of all the regulatory mechanisms and functions a protein can carry out. Here, we report a gel composition improving the electrophoretic separation of deamidated forms of Bcl-xL generated either by mutagenesis or by alkaline treatment. Importantly, this new gel formulation proved efficient to provide the long-sought evidence that even doubly-deamidated Bcl-xL remains eligible for regulation by phosphorylation.

The distribution of the pro-apoptotic protein Bax in the outer mi-tochondrial membrane (OMM) is a central point of regulation of apoptosis. It is now widely recognized that parts of the endoplasmic reticulum (ER) are closely associated to the OMM, and are actively involved in different signaling processes. We addressed a possible role of these domains, called Mitochon-dria-Associated Membranes (MAMs) in Bax localization and function, by ex-pressing the human protein in a yeast mutant deleted of MDM34, a ERMES (ER-Mitochondria Encounter Structure) component. By affecting MAMs stabil-ity, the deletion of MDM34 altered Bax mitochondrial localization, and de-creased its capacity to release cytochrome c. Furthermore, the deletion of MDM34 decreased the size of an incompletely released, MAMs-associated pool of cytochrome c.

The distribution of the pro-apoptotic protein Bax in the outer mitochondrial membrane (OMM) is a central point of regulation of apoptosis. It is now widely recognized that parts of the endoplasmic reticulum (ER) are closely associated to the OMM, and are actively involved in different signalling processes. We adressed a possible role of these domains, called Mitochondria-Associated Membranes (MAMs) in Bax localization and fonction, by expressing the human protein in a yeast mutant deleted of MDM34, a ERMES component (ER-Mitochondria Encounter Structure). By affecting MAMs stability, the deletion of MDM34 altered Bax mitochondrial localization, and decreased its capacity to release cytochrome c. Furthermore, the deletion of MDM34 decreased the size of an uncompletely released, MAMs-associated pool of cytochrome c.

The four mammalian peroxidases (myeloperoxidase, eosinophilperoxidase, lactoperoxidase, and thyroid peroxidase) are widely studied in the literature. They catalyze the formation of antimicrobial compounds and participate in innate immunity. Owing to their properties, they are used in many biomedical, biotechnological, and agro-food applications. We decided to look for an enzyme that is easiest to produce and much more stable at 37 °C than mammalian peroxidases. To address this question, a peroxidase from Rhodopirellula baltica, identified by bioinformatics tools, was fully characterized in this study. In particular, a production and purification protocol including the study of heme reconstitution was developed. Several activity tests were also performed to validate the hypothesis that this peroxidase is a new homolog of mammalian myeloperoxidase. It has the same substrate specificities as the human one and accepts I−, SCN−, Br−, and Cl− as (pseudo-) halides. It also exhibits other auxiliary activities such as catalase and classical peroxidase activities, and it is very stable at 37 °C. Finally, this bacterial myeloperoxidase can kill the Escherichia coli strain ATCC25922, which is usually used to perform antibiograms.

We report the stabilization of all-aqueous droplets upon addition of ethanol, which were further transformed into robust capsules. An all-aqueous emulsion consisting of dextran (Dex)-rich droplets in a polyethylene glycol (PEG)-rich continuous phase was used as templates. Addition of ethanol induced gelation of dextran, forming aggregated pellets of poor interest. However, this feature was prevented by initially adding bovine serum albumin (BSA) or positively charged silica particles so that in this case, stable droplets formed upon solvent addition, which no longer coalesced with time. An alternative method consisting of pouring concentrated Dex solution in a mixture of PEG, ethanol and BSA or particles, also afforded stable droplets. These stable droplets were further converted into robust capsules, using carbodiimide chemistry or silylation. We expect this method for preparing capsules to be of interest for various applications in the field of microencapsulation.