International Journal on Recent and Innovation Trends in Computing and Communication ISSN: 2321-8169 Volume: 5 Issue: 5 981 – 987 _______________________________________________________________________________________________ 981 IJRITCC | May 2017, Available @ http://www.ijritcc.org _______________________________________________________________________________________ In Silico Structural, Functional and Phylogenetic Analyses of Corynebacterium Aspartokinase: An Enzyme of Aspartate Family of Amino Acids Krishnendu Pramanik, Pooja Rajbhar, Tithi Soren, Tushar Kanti Maiti* Microbiology Laboratory, Department of Botany, The University of Burdwan Burdwan, PIN-713104, West Bengal, India *Corresponding author: tkmbu@yahoo.co.in Abstract—Aspartokinase is the enzyme of the aspartate family of amino acid biosynthesis that catalyzes first reaction in biosynthesis of Aspartate family. This enzyme has an important role for hyper production of the Lysine or methionine or threonine by microbial fermentation. The present study was undertaken to determine the in silico analysis of the aspartokinase of Corynebacteriumglutamicum. In silicoanalysis ofAspartokinase protein of Corynebacteriumglutamicumrevealed that it is a thermostable, acidic protein having molecular weight of about 45kDa. The 3D structure and protein model with functional characters of this protein has predicted. This computational analysis might assist with useful information required during wet lab experiments. Keywords-Aspartokinase; Corynebacterium; in silico analysis; microbial fermentation __________________________________________________*****_________________________________________________ I. INTRODUCTION Aspartokinase (EC 2.7.2.4) is the first enzyme of the aspartate family of amino acids biosynthesis that catalyzes the phosphorylation of the beta carboxyl group of aspartic acid with ATP to yield 4-phospho-L-aspartate, which is involved in the branched biosynthetic pathway leading to the biosynthesis of amino acids viz. lysine, threonine, isoleucine and methionine. Lysine is one of the earliest amino acids to be produced by large scale by microbial fermentation. Interestingly this enzyme has an important role for hyper production of the Lysine or methionine or threonine as it has been regulated and represses by end products. Amino acids are main components of protein which is one of the three essential nutritional components. All amino acids occurring in proteins are in L-form and only amino acids of this form are utilized in the living body. Thus L-amino acids of usually required for human and animal consumption [1]. L- amino acids have wide spectrum of commercial use as food additives , food supplements, infusion compounds therapeutic agents and precursors for the synthesis of peptides or agrochemicals [2]. The taste of the food is an important factor as their nutritional value, considering that amino acid provides one of the contributions to food taste. L-glutamic acid which is ubiquitous in animal and vegetables can enhance or improve the taste and flavor of the natural food stuffs [1]. It is also used in various industries for the manufacture of various chemicals. Some amino acids playing specific physiological role and which are used for therapeutic purposes. Amino acids are also utilized as raw materials for the synthesis of peptides used as medicine and diagnostics such as glutathione, thyrotropin releasing hormone (TRH),pentagastrin peptide, luteinizing hormone releasing hormone (LHRH), and so on [1]. As technology advances and the understanding of the functions and propertiesof amino acids increases, the commercial applications of amino acids are also increasing. New production technology and large scale production of amino acids are making it more economical and thereby increasing its user base and usage rate. Some of the companies in this industry are Ajinomoto, RSP amino acids, Biaffin, AnaSpec, ChemPepInc, IRIS Biotech, PepTech Corporation and Synthetech.. Ajinomoto is one of the leading manufacturers of amino acids. Corynebacteriumis an aerobic gram positive rod shaped bacterium which is used for the industrial production of amino acids e.g. L-lysine and L-glutamate. C.glutamicum is widely used for the biotechnological production of > 1,500,000 tons of L-glutamate per year and > 750,000 tons of L-lysine per year and several other amino acids [3]. Moreover, aspartokinase is the only enzyme involved in the lysine biosynthesis in C.glutamicum which is known to be controlled in its activity. Analysis of lysine formation revealed that overexpression of the gene for the feedback resistant aspartokinase alone suffices to achieve lysine secretion in the wild type [2]. Considering the importance of this enzyme in Aspartate family of amino acids and lysine overproduction the present study was undertaken to determine the in silico analysis of the Aspartokinase of Corynebacterium. The present investigation envisaged the computational prediction of secondary, tertiary structure of Aspartokinase protein of C.glutamicum and their functional characterization including protein-protein interaction. Attempts were also made to predict the phylogenetic relation of the protein among the different spp. and strains of Corynebacterium. II. MATERIALS AND METHODS A. Sequence retrieval and cDNA acquisition The National Center for Biotechnology Information (NCBI) (http://www.ncbi.nml.nih.gov/ ) houses a series of databases relevant to biotechnology and biomedicine and is an important resource for the bioinformaticsstudies, was used for the sequence retrieval of the different species of Corynebacteriumhaving aspartokinase activity. Twenty