Absract Archive   May - 06 How safe are GM foods? Biosafety issues and safety evaluation of GM food. PART - II Introduction Food derived from biotechnology, or genetically modified food/feed, have already become available worldwide with the aim of enhancing productivity, decreasing the use of certain agricultural chemicals, modifying the inherent properties of crops, improving the nutritional value or increasing shelf-life. It is estimated that nearly 75% of processed food available in USA contains ingredients from genetically modified crops. As more and more GM crops are being developed and released for field-testing and commercialization, concerns have been expressed about the potential risks associated with their impact to human health, environment and biological diversity. Though there is no evidence that GM foods are hazardous based on experiments conducted thus far, apprehensions arise in the minds of consumers because genetic engineering crosses the species barrier, permitting gene transfer among microorganisms, plants and animals. Innovations in the food production processes also tend to raise suspicions. Countries, in response, have adopted different regulations in relation to the trade of such food and food ingredients. Biosafety legislation and regulatory institutions to implement them have been put in place by many countries including India, starting from the research aspects up to the marketing, post-marketing surveillance and trade of GM food and food ingredients derived from them. Scientists, industry, and the government work in tandem to assure the public of the safety of the novel food products commercialized. Authors:Indira P. Sarethy, V. R. Swamy Proteomics From Sequence to Structure(3D Structure - Modeling, Validation and Visualization) Introduction Proteins (from the Greek “protos” meaning of “primary importance”) are the chemical workhorses of the body and they are very essential for the various biological processes. Proteins are abundant in all organisms and are certainly the fundamental to life. The proteins in our body are useful in various processes such as strengthening the skeleton, assimilating food and defending against infections etc., Proteins carry out vital functions in every cell. To carry out their functions, proteins must fold into complex, flexible three-dimensional structure. Proteins function depends on its shape (i.e., three dimensional structure) and the shape of a protein depends on its primary structure (i.e., sequence of amino acids). Hence, the knowledge of proteins shape (3D structure) is very useful in understanding the various functions of proteins. 3D structure of proteins provides a solid framework for planning experiments and for the interpretation of their results. Protein structures are determined by X-ray diffraction, neytron -diffraction (in crystallized proteins) and by nuclear magnetic resonance (NMR) spectroscopy (proteins in solution) studies. These experimental structure determination methods are highly expensive, time consuming (from 1 to 5 years) due to elaborate technical procedures. And, the experimental methods are not always successful because many proteins fail to crystallize and cannot be dissolved in large quantities. The sequencing of entire genomes of various organisms generate a lot of protein sequence information. Comparatively, the rate of structure determination of sequenced proteins is very low due to the above said difficulties. Thus, the difference between the number of known protein sequences and the number of experimentally determined three-dimensional structures is widening rapidly. But, the 3D structure of proteins can be predicted (approximate structures) with the help of protein structure prediction software tools and servers if the primary structure (amino acid sequence) of a protein is known. Predicting the three dimensional structure of proteins from its primary structure is one of the most significant task tackled in computational structural biology and theoretical chemistry. Bioinformaticians and chemists from all over the world are analyzing and examining the complex structure of proteins and their functions using structure prediction methods to learn more about therapies for the human body. There are various methods such as homology modeling, threading and ab initio for predicting the structure of proteins. Among all, an easiest and important method for predicting the 3D structure of proteins from its sequence is homology modeling. The databases, ModBase (http://alto.compbio.ucsf.edu/modbase-cgi/index.cgi) and 3Dcrunch (http://www.expasy.org/ swissmod/SM_3DCrunch.html) consist of protein structures obtained by homology modeling. In this article, the important steps to be followed in homology modeling of proteins, useful tools, techniques and applications of homology modeling are discussed with examples. Three-dimensional structure modeling for the protein sequence, K1510_HUMAN Protein KIAA1510 precursor (Probable collagen protein) retrieved from SwissProt database [Protein ID: Q9P218] using automated homology modeling server EsyPred, validation of the built model using the RamPage, ProQ and CE servers and 3D structure visualization using the tool RasMol is also discussed. Author:K.Sivakumar