Bioinformatics

Centrifugation separation techniques The sedimentation rate of the analyte particles in a suspension is dependent upon following properties: ·          Size of the particle ·          Medium ·          External forces applied Stokes’s law is applicable whenever the centrifugal force of ωr 2 is used to carry out sedimentation. Here ω represents the rotational angular velocity and r is representing the distance from the diameter of the analyte particle to the axis of rotation. dr/dt = 2r 2 p (ρ p - ρ m ) ω 2 r/ 9η In this equation dr/dt is the particle’s velocity; η is the viscosity of the medium, r p is the particle’s radius and (ρ p - ρ m ) difference in the density of the particle and the density of the medium. There are various techniques which involve the use of centrifugal force for the separation of particles based upon their rates of sedimentation. These sub...

Centrifugal field flow fractionation: Centrifugal FFF is basically a new name given to Sedimentation FFF after further developments in it. The specialty of this Centrifugal FFF is that it involves the use of centrifugal force as the externally applied force which is the basic element required in the separation of the analyte particles. Channel used in this technique is in the form of a ring which spins at 4900 rpm.  This technique is effective in the separation, characterization and purification of micron-sized particles of any type of analyte. It allows for the separation of particles with only a 5% difference in size. Mode of elution In Centrifugal or sedimentation FFF the elution is carried out by hyperlayer mode. The other two modes of elution fail to explain that for the particles having the size less than 1 µm the retention ratio increases with the increase in velocity of flow. In other words the transport velocity is variable for the particles whose size i...

Field Flow Fractionation Field flow fraction consists of a wide variety of separation methods for which are used for the purification and characterization of superamolecular compounds like macromolecules, colloids, particles, gels, emulsions and cells. So it has applications especially in the field of biological sciences. It consists of various sub-techniques and separation devices which are used for the separation and characterization of the particles ranging in size from 10-3 to 102 µm.  These sub-techniques of the FFF are capable of separating the particles on the basis of their physical properties like charge, mass, size and density. The basic concept of Filed flow fractionation for the first time was given in 1960s by J. Calvin Giddings. Field flow fractionation is considered to be the hybrid of chromatography, electrophoresis and ultracentrifugation all of which are field-driven methods.  Like ultracentrifugation is requires a field force and like chromat...

Comparing Eukaryotic and Prokaryotic Translation The translation process is very similar in prokaryotes and eukaryotes. Although different elongation, initiation, and termination factors are used, the genetic code is generally identical. As previously noted, in bacteria, transcription and translation take place simultaneously, and mRNAs are relatively short-lived. In eukaryotes, however, mRNAs have highly variable half-lives, are subject to modifications, and must exit the nucleus to be translated; these multiple steps offer additional opportunities to regulate levels of protein production, and thereby fine-tune gene expression. A major difference between eukaryotes and prokaryotes is that, in a typical eukaryotic cell, protein synthesis takes place in the cytoplasm while transcription and RNA processing take place in the nucleus. In bacteria, these two processes can be coupled so that protein synthesis can start even before transcription has finished. The steps of protein synthesis...

  BioSPICE   Dashboard Bio-SPICE, an open source framework and software toolset for Systems Biology, is intended to assist biological researchers in the modeling and simulation of spatio-temporal processes in living cells. In addition, our goal is to develop and serve a user community committed to using, extending and exploiting these tools to further our knowledge of biological processes.   BioUML BioUML is Java framework for systems biology. It spans the comprehensive range of capabilities including access to databases with experimental data, tools for formalized description of biological systems structure and functioning, as well as tools for their visualization and simulations.   CADLIVE CADLIVE is a system for constructing large-scale biological networks (metabolic and gene regulatory networks) using GUI (Graphic User Interface) and saving them as regulator reaction equations in a database in the format compatible to a simulator. It has been deve...