ASCs derived from burn patients are more prone to increased oxidative metabolism and reactive oxygen species upon passaging.

Background: Patients with severe burn injury (over 20% of the total body surface area) experience profound hypermetabolism which significantly prolongs wound healing. Adipose-derived stem cells (ASCs) have been proposed as an attractive solution for treating burn wounds, including the potential for autologous ASC expansion. While subcutaneous adipocytes display an altered metabolic profile post-burn, it is not known if this is the case with the stem cells associated with the adipose tissue.

Identification of methionine sulfoxide diastereomers in immunoglobulin gamma antibodies using methionine sulfoxide reductase enzymes.

Light-induced formation of singlet oxygen selectively oxidizes methionines in the heavy chain of IgG2 antibodies. Peptide mapping has indicated the following sensitivities to oxidation: M252 > M428 > M397. Irrespective of the light source, formulating proteins with the free amino acid methionine limits oxidative damage.

Accumulation of succinimide in a recombinant monoclonal antibody in mildly acidic buffers under elevated temperatures.

Purpose: The purpose of this paper was to identify the location of a succinimide and determine the rate of its formation and hydrolysis in a recombinant human monoclonal IgG2 antibody aged in mildly acidic buffers at elevated temperatures.

Materials And Methods: Cation exchange (CEX) HPLC separated multiple Main Peaks and high levels (up to 50%) of basic variants, the identification of which was an analytical challenge and required several complementary techniques. The relative abundance of the CEX basic variants was used to quantify the percentage of succinimide and to study the rates of its formation and hydrolysis.

18O labeling method for identification and quantification of succinimide in proteins.

We have developed a new method for identification and quantification of succinimide in proteins. The method utilizes 18O water to monitor succinimide hydrolysis. 18O-labeled isoaspartic acid and aspartic acid peptides were produced by hydrolysis of a succinimide-containing protein in 18O water (H218O) followed by tryptic digestion in regular water (H216O).

Crystal structure of the dioxygen-bound heme oxygenase from Corynebacterium diphtheriae: implications for heme oxygenase function.

HmuO, a heme oxygenase of Corynebacterium diphtheriae, catalyzes degradation of heme using the same mechanism as the mammalian enzyme. The oxy form of HmuO, the precursor of the catalytically active ferric hydroperoxo species, has been characterized by ligand binding kinetics, resonance Raman spectroscopy, and x-ray crystallography. The oxygen association and dissociation rate constants are 5 microm(-1) s(-1) and 0.

The crystal structures of the ferric and ferrous forms of the heme complex of HmuO, a heme oxygenase of Corynebacterium diphtheriae.

Crystal structures of the ferric and ferrous heme complexes of HmuO, a 24-kDa heme oxygenase of Corynebacterium diphtheriae, have been refined to 1.4 and 1.5 A resolution, respectively.

Solution 1H NMR investigation of the active site molecular and electronic structures of substrate-bound, cyanide-inhibited HmuO, a bacterial heme oxygenase from Corynebacterium diphtheriae.

The molecular structure and dynamic properties of the active site environment of HmuO, a heme oxygenase (HO) from the pathogenic bacterium Corynebacterium diphtheriae, have been investigated by (1)H NMR spectroscopy using the human HO (hHO) complex as a homology model. It is demonstrated that not only the spatial contacts among residues and between residues and heme, but the magnetic axes that can be related to the direction and magnitude of the steric tilt of the FeCN unit are strongly conserved in the two HO complexes. The results indicate that very similar contributions of steric blockage of several meso positions and steric tilt of the attacking ligand are operative.