Search results for "Protein purification"

Purification and characterisation of a plasmin-sensitive surface protein of Staphylococcus aureus.

1996

Certain methicillin-resistant Staphylococcus aureus strains contain a 230-kDa cell-wall protein which is not present on the surface of other staphylococci. The presence of this 230-kDa protein is associated with a negative test result in commercial assays designed to detect fibrinogen-binding proteins and/or protein A on the staphylococcal surface. We have purified and partially characterised the 230-kDa protein from a lysostaphin digest of a non-agglutinating methicillin-resistant S. aureus strain. Partial amino acid sequence data obtained from the purified protein did not reveal any significant similarities to known proteins which indicates that the protein is novel. The 230-kDa protein w…

Rapid detergent exchange in solutions of the membrane protein bacteriorhodopsin by preparative high-performance liquid chromatography (HPLC)

1984

Superparamagnetic γ-Fe2O3 nanoparticles with tailored functionality for protein separation

2007

Polymer coated superparamagnetic gamma-Fe(2)O(3) nanoparticles were derivatized with a synthetic double-stranded RNA [poly(IC)], a known allosteric activator of the latent (2-5)A synthetase, to separate a single 35 kDa protein from a crude extract which cross reacted with antibodies raised against the sponge enzyme.

2016

Protein export is central for the survival and virulence of intracellular P. falciparum blood stage parasites. To reach the host cell, exported proteins cross the parasite plasma membrane (PPM) and the parasite-enclosing parasitophorous vacuole membrane (PVM), a process that requires unfolding, suggestive of protein translocation. Components of a proposed translocon at the PVM termed PTEX are essential in this phase of export but translocation activity has not been shown for the complex and questions have been raised about its proposed membrane pore component EXP2 for which no functional data is available in P. falciparum. It is also unclear how PTEX mediates trafficking of both, soluble as…

Multifunctional polymer-derivatized γ-Fe2O3 nanocrystals as a methodology for the biomagnetic separation of recombinant His-tagged proteins

2008

Abstract Multifunctional polymer-derivatized superparamagnetic iron oxide (γ-Fe2O3) nanoparticles were prepared for biomagnetic separation of histidine-tagged recombinant proteins building up a faster and efficient method for protein separation by making use of their intrinsic magnetic properties. Using polymer bound γ-Fe2O3 nanocrystals, a 6× histidine-tagged recombinant protein (silicatein) with a molecular weight of 24 kDa has been isolated and purified. The supermagnetic iron oxide nanocrystals were characterized by transmission electron microscopy (TEM), high-resolution TEM (HRTEM), SQUID and Mossbauer and the polymer functionalization of the γ-Fe2O3 nanocrystals was monitored by UV–vi…

Packings and stationary phases for biopolymer separations by HPLC

1987

Packings and stationary phases applied to high resolution separations of proteins, enzymes, and nucleic acids must satisfy a series of distinct criteria that are different from those usually required by HPLC of low molecular weight non-biologically active analytes. These requirements have been met through substantial improvements in classical gel media together with novel developments in silica supports, and have led to a family of products with tailor-made and reproducible properties. Supports consisting of cross-linked organic gels, and inorganic materials (mostly silicas) are now available with graduated particle sizes, pore sizes, porosities and surface areas as well as non-porous beads…

Efficient Extraction of Olive Pulp and Stone Proteins by using an Enzyme-Assisted Method

2014

An efficient protein extraction protocol for proteins from olive pulp and stone by using enzymes was developed. For this purpose, different parameters that affect the extraction process, such as enzyme type and content, pH, and extraction temperature and time, were tested. The influence of these factors on protein recovery was examined using the standard Bradford assay, while the extracted proteins were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The best extraction conditions were achieved at pH 7.0 and 5% (v/v) Palatase® 20000 L (lipase) for pulp and Lecitase® Ultra (phospholipase) for stone proteins. The optimal extraction temperature and time w…

Optimised lyophilisation-based method for different biomolecule single-extractions from the same rat brain sample: Suitability for RNA and protein ex…

2019

Abstract Background Optimisation of tissue processing procedures in preclinical studies reduces the number of animals used and allows integrated multilevel study in the same sample. Multiple extraction of different biomolecules from the same sample has several limitations. New method Using brain samples from rats subjected to ischemic stroke, we combined lyophilisation of flash-frozen tissue, mechanical pulverisation and cryopreservation in a method to optimise tissue handling and preservation for independent RNA or protein single-extract methods, and subsequent RT-qPCR or Western blot analyses. Results Lyophilisation resulted in 70% tissue weight loss. RNA (OD260/280∼1.8) and protein yield…

Differential Proteomics Based on 2D-Difference In-Gel Electrophoresis and Tandem Mass Spectrometry for the Elucidation of Biological Processes in Ant…

2017

Proteomics based on 2D-Difference In Gel Electrophoresis (2D-DIGE) coupled with mass spectrometry (MS) procedures can be considered a “gold standard” to determine quantitatively and comparatively protein abundances in cell extracts from different biological sources/conditions according to a gel-based approach. In particular, 2D-DIGE is used for protein specie separation, detection, and relative quantification, whenever tandem MS is used to obtain peptide sequence information that is managed according to bioinformatic procedures to identify the differentially represented protein species. The proteomic results consist of a dynamic portray of over- and down-represented protein species that…

NovelAmycolatopsis balhimycinabiochemical abilities unveiled by proteomics

2014

Amycolatopsis balhimycina DSM5908 is an actinomycete producer of balhimycin, an analogue of vancomycin, the antibiotic of ‘last resort’ against multidrug-resistant Gram-positive pathogens. Most knowledge on glycopeptide biosynthetic pathways comes from studies on A. balhimycina as this strain, among glycopeptide producers, is genetically more amenable. The recent availability of its genome sequence allowed to perform differential proteomic analyses elucidating key metabolic pathways leading to antibiotic production in different growth conditions. To implement proteomic data on A. balhimycina derived from 2-DE approaches and to identify novel components, a combined approach based on protein …