DioxolaneA3-phosphatidylethanolamines are generated by human platelets and stimulate neutrophil integrin expression.

Activated platelets generate an eicosanoid proposed to be 8-hydroxy-9,10-dioxolane A3 (DXA). Herein, we demonstrate that significant amounts of DXA are rapidly attached to phosphatidylethanolamine (PE) forming four esterified eicosanoids, 16:0p, 18:0p, 18:1p and 18:0a/DXA-PEs that can activate neutrophil integrin expression. These lipids comprise the majority of DXA generated by platelets, are formed in ng amounts (24.

Mass Spectrometry Imaging of the Hypoxia Marker Pimonidazole in a Breast Tumor Model.

Although tumor hypoxia is associated with tumor aggressiveness and resistance to cancer treatment, many details of hypoxia-induced changes in tumors remain to be elucidated. Mass spectrometry imaging (MSI) is a technique that is well suited to study the biomolecular composition of specific tissue regions, such as hypoxic tumor regions. Here, we investigate the use of pimonidazole as an exogenous hypoxia marker for matrix-assisted laser desorption/ionization (MALDI) MSI.

Functional Exchangeability of Oxidase and Dehydrogenase Reactions in the Biosynthesis of Hydroxyphenylglycine, a Nonribosomal Peptide Building Block.

A key problem in the engineering of pathways for the production of pharmaceutical compounds is the limited diversity of biosynthetic enzymes, which restricts the attainability of suitable traits such as less harmful byproducts, enhanced expression features, or different cofactor requirements. A promising synthetic biology approach is to redesign the biosynthetic pathway by replacing the native enzymes by heterologous proteins from unrelated pathways. In this study, we applied this method to effectively re-engineer the biosynthesis of hydroxyphenylglycine (HPG), a building block for the calcium-dependent antibiotic of Streptomyces coelicolor, a nonribosomal peptide.

Human platelets generate phospholipid-esterified prostaglandins via cyclooxygenase-1 that are inhibited by low dose aspirin supplementation.

Oxidized phospholipids (oxPLs) generated nonenzymatically display pleiotropic biological actions in inflammation. Their generation by cellular cyclooxygenases (COXs) is currently unknown. To determine whether platelets generate prostaglandin (PG)-containing oxPLs, then characterize their structures and mechanisms of formation, we applied precursor scanning-tandem mass spectrometry to lipid extracts of agonist-activated human platelets.