Prefractionation using microscale solution IEF.

Proteomics often involves systematic analyses of proteomes that are constantly changing in response to changes in the environment of the cell, tissue, or organism being analyzed. Due to limitations of all current protein profiling methods, powerful, reliable proteome prefractionation methods prior to two-dimensional electrophoresis (2DE) gels or alternative non-2DE gel methods are needed for in-depth quantitative comparisons of the complex proteomes typically encountered with samples from higher eukaryotes. The microscale solution isoelectrofocusing (MicroSol IEF) fractionation method is capable of reproducibly dividing complex proteomes into as many as seven well-resolved fractions based on the proteins' pIs on a small volume scale ( approximately 0.

Protein detection in gels without fixation.

A number of alternative methods are described for detecting proteins in polyacrylamide gels that do not require fixation of the protein either prior to staining or in conjunction with staining. The primary advantage of avoiding fixation is that this makes it easier to remove proteins of interest from the gels for subsequent analysis. In general, the sensitivity of protein detection methods that avoid fixation is lower than for detection methods using fixation.

Proteome analysis of Halobacterium salinarum and characterization of proteins related to the degradation of isopropyl alcohol.

We reported in a previous study that proteomic approach, coupled with genomic techniques, could be used to screen and develop multiple candidates for halophilic enzymes from Halobacterium salinarum. In order to evaluate the biodegradation of isopropyl alcohol (IPA) by H. salinarum, the amounts of residual IPA and acetone generated in the growth media were determined using a gas chromatography-flame ionization detector (GC-FID).

Higher dimensional (Hi-D) separation strategies dramatically improve the potential for cancer biomarker detection in serum and plasma.

The plasma proteome has a wide dynamic range of protein concentrations and is dominated by a few highly abundant proteins. Discovery of novel cancer biomarkers using proteomics is particularly challenging because specific biomarkers are expected to be low abundance proteins with normal blood concentrations of low nanograms per milliliter or less. Conventional, one- and two-dimensional proteomic methods including 2D PAGE, 2D DIGE, LC-MS/MS, and LC/LC-MS/MS do not have the capacity to consistently detect many proteins in this range.

Halophile aldehyde dehydrogenase from Halobacterium salinarum.

Halobacterium salinarum is a member of the halophilic archaea. In the present study, H. salinarum was cultured at various NaCl concentrations (3.

Plasma protein level changes in waste incineration workers exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin.

TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) is a chemical compound which is known to induce severe reproductive and developmental problems, immune system damage, and interference with regulatory hormones. To characterize changes in the expression of plasma proteins caused by exposure to TCDD, we analyzed plasma samples from workers at municipal incinerators using two-dimensional gel electrophoresis (2-DE). Proteins exhibiting differences in expression were identified by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) and electrospray ionization quadrupole (ESI-Q) TOF mass spectrometry.

Proteomic characterization of rat liver exposed to 2,3,7,8-tetrachlorobenzo-p-dioxin.

Dioxins are a class of polyhalogenated aromatic hydrocarbons that induce a wide spectrum of toxic responses in experimental animals. In this study, 2,3,7,8-tetrachlorobenzo-p-dioxin (TCDD) was exposed to two SD rat groups; one group for short-term exposure at a single dose of 1, 10, 20 and 50 mug/kg body weight (group 1) and the other for long-term exposure at daily and-low dose of 0.01, 0.

An efficient proteomics based strategy for the functional characterization of a novel halophilic enzyme from Halobacterium salinarum.

The extremely halophilic archaeon, Halobacterium salinarum grows in environments containing over 25% NaCl. The enzymes of this organism have thus been adapted to be active and stable in hypersaline conditions, which makes them strong candidates as robust industrial enzymes. In this study, the proteomics approach was applied to screen novel halophilic enzymes.

Proteomics of Halophilic archaea.

Halophilic archaea is a member of the Halobacteriacea family, the only family in the Halobacteriales order. Most Halophilic archaea require 1.5M NaCl both to grow and retain the structural integrity of the cells.

Identification and characterization of inosine monophosphate dehydrogenase from Halobacterium salinarum.

Extremely halophilic Archaea, Halobacterium salinarum live in hypersaline habitats and maintain an osmotic balance of their cytoplasm by accumulating high concentrations of salt (mainly KCl). Therefore, their enzymes adapted to high NaCl concentrations offer a multitude of acutal or potential applications such as biocatalysts in the presence of high salt concentrations. In this study, the protein expression profile of H.

Differential expression of proteins in rat plasma exposed to benzene.

Benzene, a ubiquitous environmental contaminant, is an important solvent in the chemical industry and is also known as a constituent of petroleum. It has been reported that benzene is associated with hematotoxicity including leukemia in humans and cancer in laboratory animals. To study protein expression alterations in rat plasma exposed to benzene, rats were exposed to levels of 1, 10, 100 ppm benzine for 6 h/day and 5 d/week for 2 or 6 weeks.

Identification of a novel protein D3UPCA from Halobacterium salinarum and prediction of its function.

Halobacterium salinarum is an extremely halophilic archaea, which is able to live in highly saline environments. In a recent study, several halophilic archaea were found to have the ability to biodegrade organic hydrocarbon pollutants, but protein information regarding hydrocarbon degradation and tolerance in halophilic archaea has been relatively rare. In this study, the protein expression profile of H.

Analysis of differentially regulated proteins in TM4 cells treated with bisphenol A.

BPA, bisphenol A, a monomer of epoxy resins and polycarbonate plastic, is used in many consumer products including the plastic linings of cans for food and babies' bottles. BPA has been reported to cause reproductive toxicity and affects cells in rats and mice at high doses. In this study, the effect of BPA on protein expression in TM4 cells (a mouse Sertoli cell line) known to play an essential role in Spermatogenesis was investigated by two-dimensional electrophoresis (2-DE).

Proteomic analysis of plasma proteins of workers exposed to benzene.

In this study, we analyzed the proteins in plasma of workers exposed to benzene by two-dimensional gel electrophoresis, in the hope of finding a specific protein suitable for the biomonitoring of benzene exposure. Comet assays were also carried out to evaluate lymphocytes DNA damage. Fifty workers from a printing company and 38 matched unexposed healthy subjects were enrolled in the study.

Monitoring protein expression by proteomics: human plasma exposed to benzene.

Low levels and long term exposure to benzene is associated with hematotoxicity including aplastic anemia, acute myelogenous leukemia, and lymphoma. Current biomonitoring methods such as urinary phenol, S-phenylmercapturic acid, and trans-trans muconic acid were found to be unreliable as analytical methods to detect benzene exposure. Therefore, to search for a specific protein for biomonitoring benzene exposure, we investigated plasma proteins from workers (n = 50) at a printing company who were exposed to benzene, by two-dimensional gel electrophoresis.

Analysis of proteins expressed in rat plasma exposed to dioxin using 2-dimensional gel electrophoresis.

Dioxins are a class of polyhalogenated aromatic hydrocarbons that induces a wide spectrum of toxic responses in animals. In this study, two groups of Sprague-Dawley rats were exposed to 2,3,7,8-tetrachlorobenzo-p-dioxin (TCDD); one group received short-term exposure at a single dose of 1, 10, 20 or 50 microg/kg body weight and the other received long-term exposure to a daily low dose of 0.01, 0.

Development of an effective sample preparation method for the proteome analysis of body fluids using 2-D gel electrophoresis.

A sample preparation is still the most critical step in two-dimensional electrophoresis (2-DE) and should be optimized for each type of sample. In this study, a protein extraction method from body fluids was developed using a combined centrifugal filter device and a sample treating buffer. When plasma, amniotic fluid, urine, and tear were tested with this method, the recovery of protein reached almost 90% and high-quality separation of 2-DE gel was obtained.