Proteins molecular properties

Numerous researchers have dedicated their efforts to understanding the relationship between peptide and protein molecular properties (molecular mass and charge, hydrophobicity, surface charge anisotropy, surface area) and their retention in CEC as a function of field strength, gradient steepness, temperature, and variables related to surface characteristics of the stationary phase. So far, however, no reliable and comprehensive theory is available to model and predict peptide and protein retention, and the need to interface CEC with mass spec-... 

Kondo A and FllgashItanI K 1992 Adsorption of model proteins with wide variation In molecular properties on colloidal particles J. Colloid Interfaoe Sc/. 150 344-51... 

Chemiluminescence has been studied extensively (2) for several reasons (/) chemiexcitation relates to fundamental molecular interactions and transformations and its study provides access to basic elements of reaction mechanisms and molecular properties (2) efficient chemiluminescence can provide an emergency or portable light source (J) chemiluminescence provides means to detect and measure trace elements and pollutants for environmental control, or clinically important substances (eg, metaboHtes, specific proteins, cancer markers, hormones, DNA) and (4) classification of the hioluminescent relationship between different organisms defines their biological relationship and pattern of evolution. 

Creighton, TE. Proteins Structures and Molecular Properties, 2nd ed. New York Freeman, 1993. 

Creighton, T. E., 1984. Proteins Structure and Molecular Properties. New York W. H. Freeman and Co. An advanced textbook on die. structure and function of proteins. 

When thinking about chemical reactivity, chemists usually focus their attention on bonds, the covalent interactions between atoms within individual molecules. Also important, hotvever, particularly in large biomolecules like proteins and nucleic acids, are a variety of interactions between molecules that strongly affect molecular properties. Collectively called either intermolecular forces, van der Waals forces, or noncovalent interactions, they are of several different types dipole-dipole forces, dispersion forces, and hydrogen bonds. 

An approach to overcome the multi minima problem of proteins is simulated annealing (SA) run. Besides global molecular properties such as structural and thermal motions, functional properties of fast biological reactions can also be studied by MD. 

Most frequently, SEC with dextran-, pullulan-, or polystyrene calibration standards has been used to characterize the molecular properties of xylans. However, as for viscometric studies [108], a sufficient solvent ionic strength is a prerequisite for useful SEC measurements of charged polysaccharides, including glucuronoxylans [111-113]. An advantage of the SEC technique is that the presence of protein and phenolic components or oxidative changes can be detected by simultaneous ultraviolet (UV) detection. 

Molecular properties of the isolated protein 3.2.1. Polypeptide composition and glycosylation state... 

Patel S, Mackerell AD, Brooks CL (2004) CHARMM fluctuating charge force field for proteins II -Protein/solvent properties from molecular dynamics simulations using a nonadditive electrostatic model. J Comput Chem 25(12) 1504-1514... 

Quantitative molecular-property relationship Segregated-flow model Reduced folate carrier protein... 

Creighton TE (1993) Proteins structures and molecular properties, 2nd edn, Freeman WH... 

Two-dimensional electrophoresis is normally run so that proteins are separated from each other on the basis of a different molecular property in each dimension. The most commonly utilized method entails separation of proteins by isoelectric focusing (see below) in the first dimension, with separation in the second dimension being undertaken in the presence of SDS, thus promoting band separation on the basis of protein size. Modified electrophoresis equipment that renders two-dimensional electrophoretic separation routine is freely available. Application of biopharmaceuti-cal finished products to such systems allows rigorous analysis of purity. 

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