The transcriptome response has been analyzed in yogurt fermentation (Sieuwerts et al

The transcriptome response has been analyzed in yogurt fermentation (Sieuwerts et al., 2010) and in milk (Goh et al., 2011). Amidopyrine The first genome-scale model forL. design of novel strains. Therefore , a systems-based approach constitutes an important step toward understanding the interplay between metabolism and EPS biosynthesis and further enhances its metabolic performance intended for industrial application. In this review, primarily the microbial EPSs, their biosynthesis mechanism, and important factors for their production will be discussed. After this brief intro, recent literature on the application of omics technologies and systems biology tools for the improvement of production yields will be critically evaluated. Special focus will be given to EPSs with high market value such as xanthan, levan, pullulan, and dextran. Keywords: EPS, microbial production, exopolysaccharides, systems biology, xanthan, levan, pullulan, dextran == Introduction == Biopolymer (also called renewable polymers) is used as a term to describe polymers produced by biological systems and polymers that are not synthesized chemically but are derived from biological starting materials such as amino acids, sugars, and natural fats (Tang et al., 2012). Consequently, biopolymers can be classified because synthetic or natural polymers (Vroman and Tighzert, 2009). The biopolymers are superior to petrochemical-derived polymers in several aspects that include biocompatibility, biodegradability, and both environmental and human being compatibility. Although petroleum-based polymers have negative effects to environment and humanity such as toxicity, defiance to biodegradation, and waste build up, they have been utilized in a variety of industrial applications. Therefore , in response to these problems, biopolymers are a suitable alternative that the researchers were looking (Keshavarz and Roy, 2010). Today, several microorganisms are identified as microbial biopolymer producers and these polymers can be found because attached to the cell surface or extracted from the fermentation medium. Bacteria use these microbial biopolymers as storage materials in response to particular environmental stresses (Sanchez-Garcia et al., 2010). Due to their biological functions microbial polysaccharides can be generally classified as intracellular storage polysaccharides (glycogen), capsular polysaccharides (e. g., K30 O-Antigen), Amidopyrine and extracellular bacterial polysaccharides (for example, levan, xanthan, sphingan, Amidopyrine alginate, pullulan, cellulose, etc . ), which are important for biofilm formation and pathogenicity (Schmid and Sieber, 2015). Microbial polysaccharides that are produced by microorganisms and secreted out of the cell Rabbit polyclonal to CREB.This gene encodes a transcription factor that is a member of the leucine zipper family of DNA binding proteins.This protein binds as a homodimer to the cAMP-responsive are defined as exopolysaccharides (EPSs). In nature, they have a significant role intended for protection from the cell, adhesion of bacteria tosolid surfaces, and participating in cell-to-cell interactions (Nicolaus et al., 2010). In recent years, there is a significant interest on microbial EPSs since they have different structural and functional properties (Morris and Harding, 2009). EPSs are important resources for hydrocolloids utilized in food, pharmaceutical, chemical, and many other industries (Ahmad et al., 2015). Due to their many interesting physicochemical and rheological properties with novel functionality, the microbial EPSs act as new biomaterials and find a wide range of applications in many industrial sectors such as textiles, detergents, adhesives, microbial enhanced essential oil recovery (MEOR), wastewater treatment, dredging, brewing, downstream digesting, cosmetology, pharmacology, and food additives (Rhmann et al., 2015). Xanthan, dextran, and pullulan are examples of microbial polysaccharides with a considerable market due to their outstanding properties. However , plant and algal polysaccharides such as starch, galactomannans, pectin, carrageenan, and alginate still include a major part of the hydrocolloid market, which has a market value of 4 million US dollars in 2008, 3. 9 billion US dollars in 2012, and this value is expected to reach 7 billion US dollars by 2019 (Williams et al., 2007; Patel and Prajapati, 2013). Since microbial EPSs enable fast and large yielding production processes under controlled conditions, they are economically competitive to the plant and algal origin polysaccharides, which are affected by climatological and geological environmental conditions (Kaur et al., 2014). Although there is an increased attraction intended for microbial EPSs in industrial and medical applications and they are related with high-value applications, only a few bacterial EPSs have achieved to be used commercially such as xanthan, gellan, and dextran due to large production costs (Freitas et al., 2011; Llamas et al., 2012). Due to the exceptionally high production costs, microbial EPSs could never find their proper place in the polymer market and therefore, high-level EPSs generating microbial systems gain escalating industrial importance. Increasing significance of EPSs in industrial and medical biotechnology calls for the elucidation of the interrelations between metabolic pathways and biosynthesis mechanism in order to control and hence improve microbial productivity. Therefore , extensive interest offers.