Abstract Archive   April 2007 Engineering Dynamic Pathways for Biodegradable Polymer Production Introduction In the last decades, different synthetic polymers have substituted natural materials in many fields. In this age of tremendous commercial interest in renewable resource regeneration and efficient resource utilization, there is always a continuous search for perpetual recycling and reuse [Stein et al 1992, Leaversuch et al 1987]. The property of recycling refers in a way to degradability in strict biological terms. In this respect, a question arises whether or not synthetic polymers may undergo degradation by natural assemblages of microbes. Polyhydroxyalkanoates or in short PHAs are the polymers of hydroxyalkanoates, which are accumulated as a carbon and energy storage material in various microorganisms [Wang et al 1997]. When nutrient supplies are imbalanced, it is advantageous for bacteria to store excess nutrients intracellularly, especially as their general fitness is not affected. By polymerizing soluble intermediates into insoluble molecules, the cell does not undergo alterations of its osmotic state and leakage of these valuable compounds out of the cell is prevented. Consequently, the nutrient stores will remain available at a relatively low maintenance cost and with a secured return on investment. Once PHAs are extracted from the bacterial cell, however, these molecules show material properties that are similar to some common plastics such as polypropylene. The bacterial origin of the PHAs makes these polyesters a natural material, and, indeed, many microorganisms have evolved the ability to degrade these macromolecules. Besides being biodegradable, PHAs are recyclable like the petrochemical thermoplasts. Among the PHAs, polyhydroxybutyrates are one of the important classes, which are found to occur in many species like Alcaligenes eutrophus. Poly 3-hydroxybutyrate or P3HB was discovered in Alcaligenes eutrophus when Bartha plotted the first growth curves and observed an increase in the turbidity of the stationary phase of growth when cell number remained constant. PHAs have attracted much attention in terms of their material properties, which are similar to those of conventional petrochemical derived plastics. In addition, they are completely biodegradable under different effects of most environments [Doi 1990]. Authors:Nisha James,Padhmanand Sudhakar. Gene Technology: A Promising Tool for Plant Varietal Improvement Plants are primary source of energy for human being and animals. Human and animals are always dependent upon plants for their survival. For better yield and good quality, farmers are altering crops through different means and sharing advantages with society. For crop varietal development traditional plant breeding is well known technique. Plant breeding has been giving significant result in agriculture sector. But due to a number of reasons, traditional plant breeding has its own limitations. First plant breeding can be done only in two plants that are sexually compatible with each other and secondly plants are transferred along with the traits of interest including traits with undesirable effects on yield potential. Also plant breeding is a time consuming process. For developing a new plant variety with new good traits, plant breeders need to test a large population of plants. Biotechnology in recent year has created unprecedented opportunities not only for the manipulation of the biological system for benefit of mankind, but also for undertaking studies to understanding the fundamental life processes. Biotechnology has also revolutionized the research activities in the area of agriculture. Now gene technology is leading to transformation followed by regeneration of plants to give transgenic/genetically-modified plants. Carrying desirable traits like disease resistance, insect resistance, herbicide resistance and high yielding varieties of plants as well. Authors: Sudhir Sharma, Pardeep Kumar, Santosh Kumar .    Micropropagation in Phyllanthus amarus. Schum. and Thonn Introduction India, being a tropical country and rich in biodiversity, produces and exports raw medicinal plants and extracts. According to one estimate, the present world trade in plant based dry raw materials and phytochemicals is around US $ 33,000 million. These plants require biotechnological inputs to maintain their quality. (Merillon and Ramawat, 1999). Phyllanthus amarus Schum. and Thonn. ,the popular herb used for the cure of liver disorders belongs to the large and complex genus Phyllanthus in the Euphorbiaceae family. It is a small, erect, annual herb that grows 3040 cm in height, indigenous to the rainforests of the Amazon and other tropical areas throughout the world, including the Bahamas, southern India and China. This is the most widely used medicinal plant with applications against liver diseases and disorders including anemia, jaundice, liver cancer and hepatitis, biliary and urinary conditions including kidney and gallbladder stones; cold, flu, tuberculosis, etc. It is also widely employed for diabetes and hypertension as well as for its diuretic, analgesic, stomachic, antispasmodic, and cell protective properties in many other conditions. Recent interest in the possible anti viral effects especially against hepatitis B virus (HBV) which is the leading cause of liver cancer (hepatoma) has focused the need for extensive study of the biologically active compounds obtained from Phyllanthus amarus. In- vitro grown plant cells and tissues have been used extensively for the production of secondary metabolites. Once the in-vitro culture is established, it is used to achieve objectives through micropropagation, genetic manipulation or cultivation. Plant cell culture eliminates potential political boundaries or geographic barriers to production of a crop. When a valuable product is found in a wild or scarce plant species, intensive cell culture is a practical alternative to wild collection of fruits and other plant materials. Secondary products in plant cell culture can be generated on a continuous year-round basis (no seasonal constraints), production is reliable and predictable, and in at least some cases, the yield per gram fresh weight may exceed that found in nature. As the demand for the plant-derived pharmaceutical compounds is increasing, possibilities for mass production need to be explored. Availability of the plant is subjected to seasonal variation leading to uncertainty in stable supply throughout the year. Plant production under controlled conditions of in vitro system can possibly eliminate these problems. Therefore, establishing a suitable micropropagation protocol for this high value plant will have the potential of providing a better source for continuous supply of plants to be used as a standard material in the field of drug research as well as manufacturing of drugs. Authors:Anju Pappachan, R.Gnanam K.S. Ambika. RNA Interference A dream tool for Censorship and Gene Silencing Introduction The flow of genetic information proceeds usually from DNA through RNA to protein. A protein's amino acid sequence reflects the amino acid sequence of its mRNA. This messenger is a complementary copy of portion of the DNA genome. No cell could function amid the resulting cacophony. So cells muzzle most genes, allowing the appropriate subset to be heard. In most cases, a gene's DNA code is transcribed into messenger RNA only if a particular protein assemblage has docked onto a special regulatory region in the gene. Some genes however, are so subversive that they should never be given freedom of expression. If the genes from mobile genetic elements were to successfully broadcast their RNA messages, they could jump from spot to spot on the RNA, causing cancer or other diseases. Similarly, viruses, if allowed to express their messages unchecked, will hijack the cell's protein production facilities to crank out viral proteins. Cells have ways of fighting back. Just within the past several years a more precise and - for the purpose of research and medicine more powerful security apparatus built into nearly all plant and animal cells called RNA interference, or RNAi. When a threatening gene is expressed, the RNAi machinery silences gene by intercepting and destroying only the offender's messenger RNA, without disturbing the messages of other genes. Purple petunias offered the first clues to the existence of gene censors in plants. Richard A. Jorgensen and, independently Joseph Mol inserted into purple flowered petunias additional copies of their native pigment gene. They were expecting the engineered plants to grow flowers that were even more vibrantly violet. But instead they obtained blooms having patches of white. They concluded that extra copies were somehow triggering censorship of the purple pigment genes including those natural to the petunias resulting in variegated or even albino like flowers. They named the observed phenomenon "co-suppression", since the expression of both the introduced gene and the homologous endogenous gene was suppressed. First thought to be a quirk of petunias, co-suppression was later seen in fungi, fruit flies and other organisms. In 1998, Andrew Fire and Craig C. Mello reported a potent gene silencing effect after injecting double stranded RNA into C. elegans. They coined the term RNAi. RNA interference was soon observed in algae, flatworms, and fruit flies. In principle, scientists might be able to invent ways to direct RNA interference to stifle genes involved in cancer, viral infection or other diseases. If so, the technology could form the basis for a new class of medicines Mechanism of RNA interference Authors: A.koteeswaran, M.Mohan. Enzyme Stabilization Using Trehalose Sugar -A Major Break Through Enzymes are biocatalysts (the catalysts of cell metabolism). However, this concept has expanded beyond its physiological meaning, a biocatalyst being, in broader terms, any biological entity capable of catalyzing the conversion of a substrate into a product. Accordingly, biocatalysts can be divided in cellular (whether growing, resting or non-living cells) and non-cellular (enzymes that have been removed from the cell system that produce them). Ribozymes, abzymes and peptide mimics can also be considered as biocatalysts. Enzymes act by reducing the energy barrier (activation energy) of chemical reactions, therefore producing a dramatic increase in reaction rates, ranging from 106 to 1024 fold. Different agents, like temperature and chemicals, promote enzyme inactivation. Inactivation by chemicals can often be avoided rather easily by keeping them out of the reaction medium. Temperature, however, produces opposed effects on enzyme activity and stability and is therefore a key variable in any biocatalytic process. In fact, enzymes some times active at low temperatures and stable at high temperatures are of great technological potential. Enzyme stability, i.e. the capacity to retain activity through time, is undoubtedly the limiting factor in most bioprocesses, enzyme stabilization being then a central issue of biotechnology. In fact, biocatalyst operational stability will determine to a large extent the viability of the process, be it new or faced to compete with an already existing technology. It is reasonable then, that a significant effort in R&D in the field of biocatalysis is devoted, from different perspectives, to enzyme stabilization. Authors: P.Rajasekaran,S.Shanmugam,T. Sathish Kumar. “The Evolution of Global Intelligence: When Things Start to Think” We now have new ways of connecting people with computers; the thinking, learning and analyzing machines. These Miracle Machines make use of Artificial Intelligence (AI) and neural networks leading to the evolution of Global Intelligence. They have been successfully applied to problems in fields of pattern recognition, image processing, data compression, forecasting, and optimization to quote a few. A Neural Network is a simplified model of a biological nervous system, which is a highly interconnected network of a large number of processing elements called neurons in an architecture inspired by brain, thus it is a massive parallel distributed processing unit which can be creatively shown in the figure. There are two types of learning 1. Supervised learning. 2. Unsupervised learning. 1. In Supervised learning: A 'Teacher' is present which aims to minimize the error in order to obtain the desired output from the computed output. 2. Contrastingly in Unsupervised learning: No 'Teacher' is present in this type of learning. It learns by itself. The only disadvantage is that since it does not have a predefined set of rules to abide by; innumerable errors have been seen in this type of learning. Neural Networks have been developed into various forms; therefore they can be classified into different architectures based on requirements. They are: 1. Classical Architectures: for example- Single layer feed forward, Multi-layer feed forward, Recurrent networks, etc. 2. Non-Classical architectures: for example-Back propagation, Perceptron, ADLINE (Adaptive linear Element), Boltzmann Machine, Support Vector Machines (SVMs), Hopfield Network, ART (Adaptive Resonance Theory), Self-organizing feature map and Bayesian Networks which is our current model of interest. Authors:Kuldeep Jariwala,Jwalin Pandya,Rini Pauly.