Abstract: The present invention provides methods for crystallographic structure determination employing hydrogen exchange analysis. Hydrogen exchange analysis is used to identify unstructured regions of a protein, and then hydrogen exchange analysis repeated after the protein is admixed with candidate agents and/or conditions that may induce structure in said identified unstructured regions. Agents that induce desired structure in the protein are then employed, admixed with the protein, in co-crystallization studies for structure determination. Hydrogen exchange analysis is performed by determining the quantity of isotope and/or rate of exchange of peptide amide hydrogen(s) with isotope on a labeled protein. Proteins with agent-induced decreases in unstructured regions, and thus improved hydrogen exchange structural maps, are optimal for high quality crystallization and structure determination.

Abstract: The present invention provides methods for crystallographic structure determination employing hydrogen exchange analysis. Hydrogen exchange analysis is used to identify unstructured regions of a protein, and then hydrogen exchange analysis repeated after the protein is admixed with candidate agents and/or conditions that may induce structure in said identified unstructured regions. Agents that induce desired structure in the protein are then employed, admixed with the protein, in co-crystallization studies for structure determination. Hydrogen exchange analysis is performed by determining the quantity of isotope and/or rate of exchange of peptide amide hydrogen(s) with isotope on a labeled protein. Proteins with agent-induced decreases in unstructured regions, and thus improved hydrogen exchange structural maps, are optimal for high quality crystallization and structure determination.

Abstract: The present invention provides polynucleotides that a protein solubility responsive promoter operatively liked to a reporter gene and a genetic reporter system comprising these polynucleotides together with an expression construct for a target protein. The invention also provides cells comprising polynucleotides of the invention and the genetic reporter system. These compositions are useful to monitor the solubility of a target protein in a cell and to identify mutations to the cell or mutations to a polynucleotide encoding the target protein that alters the solubility of the target protein. The invention further provides method to identify variations in a protein biosynthetic process that alter the solubility of a target protein and methods to screen an expression library of recombinant clones to identify clones that express soluble proteins. Finally, the invention discloses a novel method of identifying an antibiotic agent.

Abstract: A process for producing and purifying peptides and for producing peptide/protein antigens for antibody production is described. The process utilizes fusion proteins and specifically fusion proteins in which the fusion protein carrier segment includes an amino acid sequence at least about 65 amino acids long and in which the amino acid sequence does not contain negative or positive charged side chains of amino acids.

Abstract: The present invention provides polynucleotides that a protein solubility responsive promoter operatively liked to a reporter gene and a genetic reporter system comprising these polynucleotides together with an expression construct for a target protein. The invention also provides cells comprising polynucleotides of the invention and the genetic reporter system. These compositions are useful to monitor the solubility of a target protein in a cell and to identify mutations to the cell or mutations to a polynucleotide encoding the target protein that alters the solubility of the target protein. The invention further provides method to identify variations in a protein biosynthetic process that alter the solubility of a target protein and methods to screen an expression library of recombinant clones to identify clones that express soluble proteins. Finally, the invention discloses a novel method of identifying an antibiotic agent.

Abstract: An automated centrifuge comprising a rotor having a plurality of sample receiving elements located in the rotor is provided. Sample processing components are structured to be insertable into any one of the receiving elements and a controller is configured to insert the sample processing components into the sample receiving elements. The sample receiving elements located in the rotor are grouped in clusters, and the cavities of each cluster are substantially parallel. Also, an automated centrifuge system comprising a rotor including a plurality of clusters of receiving elements, each element including a longitudinal axis, with the longitudinal axes of each element in a cluster being substantially parallel is provided. A plurality of sample processing components are arranged in groups, with each group configured to be received into adjacent clusters. A rotor position member is structured to determine the position of each cluster.

Abstract: This invention provides apparatus and methods that enable the direct measurement of an analyte sample in an assay well by forming an independent measuring region. The sample to be measured can be separated into portions, for example, a bound portion and a free portion. To form the independent measuring region, a layer-forming material that can restrict the passage of radiant energy that is measured by a detection device is added to the assay well. The layer-forming material forms a layer that restricts the passage of radiant energy from the region. Thus, a sample portion in one separate region may be measured by a detection device separately and independently of a portion of the sample in a different region. In one example, a second portion in another region can be separately and independently measured by a detection device without the removal of the portions from the assay well.

Abstract: The present invention presents a novel method for removing endotoxins from nucleic acids, such as DNA, RNA, or hybrids thereof, contaminated therewith. Nucleic acid solutions which can be treated using the method of this invention include, but are not limited to, lysates of gram-negative bacteria and nucleic acid solutions contaminated with endotoxins from external sources. The present method removes endotoxins from such solutions using silica-based materials, such as silica gel particles, magnetic silica particles, or diatomaceous earth. In a preferred aspect of the method of this invention, magnetic silica particles are used to isolate plasmid DNA from a lysate of gram-negative bacteria transformed with the plasmid DNA. Application of the disclosed method produces nucleic acids which are sufficiently free of endotoxin contamination to be useful for a variety of different practical applications.

Abstract: A process for pro and purifying peptides and for producing peptide/protein antigens for antibody production is described. The process utilizes fusion proteins and specifically fusion proteins in which the fusion protein carrier segment includes an amino acid sequence at least about 65 amino acids long and in which the amino acid sequence does not contain negative or positive charged side chains of amino acids.

Abstract: A process for producing and purifying peptides and for producing peptide/protein antigens for antibody production is described. The process utilizes fusion proteins and specifically fusion proteins in which the fusion protein carrier segment includes an amino acid sequence at least about 65 amino acids long and in which the amino acid sequence does not contain negative or positive charged side chains of amino acids.

Abstract: Methods, kits, and reagents for conducting site-specific mutagenesis of single or double-stranded nucleic acids which utilizes novel antibiotic resistance conferred by a mutated antibiotic resistance gene for efficient mutant selection are described.