Intriguing role of water in protein-ligand binding studied by neutron crystallography on trypsin complexes.

Hydrogen bonds are key interactions determining protein-ligand binding affinity and therefore fundamental to any biological process. Unfortunately, explicit structural information about hydrogen positions and thus H-bonds in protein-ligand complexes is extremely rare and similarly the important role of water during binding remains poorly understood. Here, we report on neutron structures of trypsin determined at very high resolutions ≤1.

Analysis of the risk factors for early failure after extracardiac Fontan operation.

Background: We analyzed risks for severe morbidity in the early period after extracardiac Fontan operation.

Methods: Between November 1995 and May 2011, 140 patients (median age, 3.8 years) underwent extracardiac Fontan operation.

Improved early postoperative outcome for extracardiac Fontan operation without cardiopulmonary bypass: a single-centre experience.

Objectives: The use of modified extracardiac Fontan operation (ECFO) for total cavo-pulmonary connection allows cardiopulmonary bypass (CPB) to be avoided and seems to improve early postoperative results. We evaluated our experience with the off-pump technique for ECFO.

Methods: Since 2009, the last 17 consecutive patients of 137 (median age 3.

Reconstructing the binding site of factor Xa in trypsin reveals ligand-induced structural plasticity.

In order to investigate issues of selectivity and specificity in protein-ligand interactions, we have undertaken the reconstruction of the binding pocket of human factor Xa in the structurally related rat trypsin by site-directed mutagenesis. Three sequential regions (the "99"-, the "175"- and the "190"- loops) were selected as representing the major structural differences between the ligand binding sites of the two enzymes. Wild-type rat trypsin and variants X99rT and X(99/175/190)rT were expressed in yeast, and analysed for their interaction with factor Xa and trypsin inhibitors.