Ordered chimerogenesis applied to CYP2B P450 enzymes.

Background: Structural studies on CYP2B enzymes identified some of the features that are related to their high plasticity. The aim of this work was to understand further the possible relationships between combinations of structural elements and functions by linking shift in substrate specificity with sequence element swaps between CYP2B6 and CYP2B11.

Methods: A series of 15 chimeras in which a small CYP2B6 sequence segment was swapped with its equivalent in CYP2B11 were constructed.

Enrichment of cholesterol in microdissected Alzheimer's disease senile plaques as assessed by mass spectrometry.

Extensive knowledge of the protein components of the senile plaques, one of the hallmark lesions of Alzheimer's disease, has been acquired over the years, but their lipid composition remains poorly known. Evidence suggests that cholesterol contributes to the pathogenesis of Alzheimer's disease. However, its presence within senile plaques has never been ascertained with analytic methods.

Sequence-independent construction of ordered combinatorial libraries with predefined crossover points.

Combinatorial libraries coding for mosaic enzymes with predefined crossover points constitute useful tools to address and model structure-function relationships and for functional optimization of enzymes based on multivariate statistics. The presented method, called sequence-independent generation of a chimera-ordered library (SIGNAL), allows easy shuffling of any predefined amino acid segment between two or more proteins. This method is particularly well adapted to the exchange of protein structural modules.

Predicting hospitalization and mortality in end-stage renal disease (ESRD) patients using an Index of Coexisting Disease (ICED)-based risk stratification model.

We evaluated the use of an additive Index of Coexisting Diseases (ICED)-based stratification schema to determine subsequent hospitalization and mortality in a hemodialysis population. Patients from five commercial health plans were stratified into low-, medium-, and high-risk groups and followed for up to 1 year. Patients were reassessed and restratified at 90-day intervals and censored when disease management ceased.

Comparative expression of the human beta(2) and beta(3) adrenergic receptors in Saccharomyces cerevisiae.

The beta(3) adrenergic receptor (beta(3)AR) is the predominant beta subtype in human brown adipocytes and is essential for regulating thermogenic lipolysis. To establish a novel experimental system for the biochemical analysis of this protein, we engineered several yeast strains. We show that the sterol background of the host strain greatly modulates the beta(3)AR expression but not in the same way as it modulates the beta(2) adrenergic receptor (beta(2)AR), the other main studied adipocyte subtype.