COVID-19: IFSO LAC Recommendations for the Resumption of Elective Bariatric Surgery.

Background: COVID-19 pandemic varies greatly and has different dynamics in every country, city, and hospital in Latin America. Obesity increases the risk of SARS-CoV-2 infection, and it is one of the independent risk factors for the most severe cases of COVID-19. Currently, the most effective treatment against obesity available is bariatric and metabolic surgery (BMS), which further resolves or improves other independent risk factors like diabetes and hypertension.

Calorimetric study of the interaction of the C2 domains of classical protein kinase C isoenzymes with Ca2+ and phospholipids.

The affinities of Ca(2+) and anionic lipid vesicles from the C2 domains of classical protein kinase C subfamily (alpha, betaII, and gamma) were studied using isothermal titration calorimetry (ITC). In addition, the thermal stability of these C2 domains in the presence of different ligand concentrations was analyzed using differential scanning calorimetry (DSC). These three closely related C2 domains bind Ca(2+) in a similar way, demonstrating the presence of two sets of sites.

Structural and thermodynamic characterization of Pal, a phage natural chimeric lysin active against pneumococci.

Pal amidase, encoded by pneumococcal bacteriophage Dp-1, represents one step beyond in the modular evolution of pneumococcal murein hydrolases. It exhibits the choline-binding module attaching pneumococcal lysins to the cell wall, but the catalytic module is different from those present in the amidases coded by the host or other pneumococcal phages. Pal is also an effective antimicrobial agent against Streptococcus pneumoniae that may constitute an alternative to antibiotic prophylaxis.

Characterization of Ejl, the cell-wall amidase coded by the pneumococcal bacteriophage Ej-1.

The Ejl amidase is coded by Ej-1, a temperate phage isolated from the atypical pneumococcus strain 101/87. Like all the pneumococcal cell-wall lysins, Ejl has a bimodular organization; the catalytic region is located in the N-terminal module, and the C-terminal module attaches the enzyme to the choline residues of the pneumococcal cell wall. The structural features of the Ejl amidase, its interaction with choline, and the structural changes accompanying the ligand binding have been characterized by CD and IR spectroscopies, differential scanning calorimetry, analytical ultracentrifugation, and FPLC.

Structural basis for chitin recognition by defense proteins: GlcNAc residues are bound in a multivalent fashion by extended binding sites in hevein domains.

Background: Many plants respond to pathogenic attack by producing defense proteins that are capable of reversible binding to chitin, a polysaccharide present in the cell wall of fungi and the exoskeleton of insects. Most of these chitin-binding proteins include a common structural motif of 30 to 43 residues organized around a conserved four-disulfide core, known as the 'hevein domain' or 'chitin-binding' motif. Although a number of structural and thermodynamic studies on hevein-type domains have been reported, these studies do not clarify how chitin recognition is achieved.