Conformational transitions in topologically constrained duplex DNA necessarily affect and are affected by other transitional processes throughout the entire molecule. This conformational interdependence of discrete sequences within a given superhelical domain arises through a requisite competition for the free energy of supercoiling. Here we present a generalized statistical mechanical analysis...

Sample preparation is key to the success of proteomics studies. In the present study, two sample preparation methods were tested for their suitability on the mature, recalcitrant leaves of six representative perennial plants (grape, plum, pear, peach, orange, and ramie). An improved sample preparation method was obtained: Tris and Triton X-100 were added together instead of CHAPS to the lysis b...

Abstract This study aims to compare the grain protein profile of four Brazilian cowpea cultivars ( BRS Aracê, Itaim, Pajeú, and Xiquexique) by two-dimensional electrophoresis (2-DE) principal component analysis (PCA). 2-DE efficiently separate profiles, showing high homogeneity among cultivars. In addition, indicated that there is a difference in abundance proteins The Aracê Xiquexique, both bi...

In this review I will describe the advances that have recently been made in "traditional" two-dimensional gel based protein expression analysis. A major jump has been made toward the automation of gel image analysis and comparison, one of the major bottlenecks in the analysis chain as well as the automation of spot excision and preparation for mass spectrometric analysis. Currently the gel-base...

The recent development of microarray technology has led statisticians and bioinformaticians to develop new statistical methodologies for comparing different biological samples. The objective is to identify a small number of differentially expressed genes from among thousands. In quantitative proteomics, analysis of protein expression using two-dimensional gel electrophoresis shows some similari...

The automated interpretation of two-dimensional gel electrophoresis images used in protein separation and analysis presents a formidable problem in the detection and characterization of ill-defined spatial objects. We describe in this paper a hierarchical algorithm that provides a robust, high-sensitivity solution to this problem, which can be easily adapted to a variety of experimental situati...

Patterns of newly synthesized proteins of Vero cells in different growth states were obtained using two-dimensional gel electrophoresis. The 240 most prevalent peptide spots were then compared. Cells in exponential growth and in the stationary phase were found to have patterns of peptide spots characteristic of their state of growth. The transition between these patterns is progressive, and the...

Biological function is mainly carried out by a dynamic population of proteins and peptides which may be used as markers for disease diagnosis, prognosis and as a guide for effective treatment. The study of proteins is called proteomics and it is generally performed by two-dimensional gel electrophoresis and mass spectrometric methods. However, gel-based proteomics is methodologically restricted...