Matrix metalloproteinase-14 mediates a phenotypic shift in the airways to increase mucin production.

Rationale: Induced mainly by cigarette smoking, chronic obstructive pulmonary disease (COPD) is a global public health problem characterized by progressive difficulty in breathing and increased mucin production. Previously, we reported that acrolein levels found in COPD sputum could activate matrix metalloproteinase-9 (MMP9).

Objectives: To determine whether acrolein increases expression and activity of MMP14, a critical membrane-bound endopeptidase that can initial a MMP-activation cascade.

Characterizing the reproducibility of a protein profiling method for the analysis of mouse bronchoalveolar lavage fluid.

The detection of biomarkers in biological fluids has been advanced by the introduction of mass spectrometry screening methods such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS), which enables the detection of the presence and the molecular mass of proteins in unfractionated mixtures. The generation of reproducible mass spectra over the course of an experiment is vital in obtaining data in which differences in protein profiles between diseased and healthy states can be assessed correctly. We have developed a protocol to automate the collection of protein profiling data from a large number of samples using MALDI-TOFMS, and we used these samples to characterize the technical reproducibility of the method.

Association of the 17-kDa extrinsic protein with photosystem II in higher plants.

The structural association of the spinach 17-kDa extrinsic protein of photosystem II with other extrinsic and membrane-bound components of the photosystem was investigated by labeling the 17-kDa extrinsic protein with the amino-group-specific reagent N-hydroxysuccinimidobiotin both on intact photosystem II membranes or as a free protein in solution. After isolation of the biotinylated molecules, the modified 17-kDa proteins were allowed to rebind to photosystem II membranes which were depleted of the 17-kDa component. Differential binding of the protein biotinylated in solution compared to unmodified 17-kDa protein or 17-kDa protein modified on PS II membranes was observed.