International Conference on Protein Engineering October 26-28, 2015 Chicago, USA

Mozhdeh Haddadi is currently pursuing MSc in Biochemistry at Tarbiat Modares University.

Bacillus amyloliquefaciens amylase (BAA) is a mesophilic and Bacillus licheniformis amylase (BLA) is a thermophilic enzyme\r\nthat both are used in industrial microbial production of enzymes as well as fine biochemical. Deep eutectic solvents (DES) are\r\nrecognized as green solvents for carbohydrates dissolution. DESs are a mixture of two or more compounds with a melting point lower\r\nthan any of its individual components. In the present study the effect of various deep eutectic solvents on the activity, stability and\r\nstructure of two related alpha amylases from Bacillus amyloliquefaciens and Bacillus licheniformis was investigated. Results showed that\r\nBLA was more active and stable in deep eutectic solvents containing 1:1 ratio of 6 M glycerol and choline chloride. Thermal stability of\r\nboth enzymes was studied by incubating each enzyme for 2 hours at different temperatures (70, 80 and 90o C) in Tris buffer (pH 7.5).\r\nThe BLA enzyme exhibited remarkable stability up to 70o C with tendency to aggregate at higher temperature. Secondary and tertiary\r\nstructural changes were analyzed using circular dichroism and fluorescence spectroscopy. Due to the hydrophobic environment of\r\nthese solvents, tertiary structural changes indicated a compact structure for both BLA and BAA. Circular dichroism analysis showed\r\n53.68% α-helix and 18.46% β-strand for BAA and 69.63% α-helix and 6.64% β-strand for BLA in DESs.

Grzegorz Lesnierowski has completed his PhD in 1998 from Agriculture University of Poznan and Postdoctoral studies in 2008 from Poznan University of Life Sciences. He\r\nhas published more than 100 papers. His principal research topics include: The technology, chemistry, hygiene and microbiology of manufacturing processes and product\r\nderived from eggs, poultry meat and other poultry raw materials; derivation of components of high utility value from egg white and yolk for food preservation, pharmacy\r\nand veterinary purposes; lysozyme modifications for widening the spectrum of its antibacterial activity and application of lysozyme antibacterial activity to food industry.

Lysozyme (E.C.3.2.17) is an enzyme widespread in nature, it is found in many biological fluids and tissues of a large number\r\nof living organisms but hen egg white is its one of the richest sources. It is a relatively small secretory protein and is known as\r\nhydrolase cutting the β-1-4 glycosidic bond in the cell walls mainly of gram-positive bacteria. Studies indicate that the range of\r\nlysozyme activity may be extended due to the chemical or physical modifications leading to changes in the conformation of enzyme\r\nmolecules and as a consequence; the production of its dimer or higher oligomeric forms. In our laboratory, we have developed\r\nseveral methods for the modification of lysozyme such as thermal, thermochemical, chemical and membrane method. The enzyme\r\nobtained using such processes as heating, oxidation or high-pressure exhibits different and quite new valuable properties. Beside\r\naction against gram-positive bacteria, it demonstrates bacteriostatic activity against Gram-negative bacteria, among them a number\r\nof food pathogens. Additionally, lysozyme modified to oligomeric forms shows many other useful properties i.e., it can modulate\r\nthe synthesis of tumor necrosis factor (TNFα) and stimulate the production and release of interferon alpha and gamma (INFα,\r\nINFγ) as well as interleukin-2 (Il-2) and interleukin-6 (Il-6) by human lymphocytes. Thanks to such valuable properties of modified\r\nlysozyme which has already found practical applications in veterinary medicine. Now, it is particularly useful in treatment of some\r\nanimal diseases as the only drug and as an agent which significantly increases efficacy of antibiotics. It is likely that soon the modified\r\nlysozyme may also turn out to be an invaluable drug in human medicine.

Madyarov Shukhrat Raimjanovich has completed his PhD from Tashkent State University and Institute of Plant Chemistry and Postdoctoral studies from Institute of\r\nBiochemistry, Institute of Physiology and Biophysics, Zoology Institute of Uzbek Academy of Sciences and Uzbek Research Institute of Sericulture of Agricultural Academy\r\nof Sciences. He has defended DSc (Biotechnology) dissertation in 2010. He has published more than 40 papers in reputed journals, 10 patents and served as an Editorial\r\nBoard Member (2000-2006) of International Journal of Industrial Entomology.

Lipolytic enzymes usually work on the surface of their insoluble substrates, self assembled in supramolecular structures. By the\r\nexample of phospholipase D (PLD) it was shown that negatively charged products PA or LPA produced during hydrolysis of initial\r\nsubstrates-bilayer РС or micellar LPС formed in the presence of Ca2+ clusters, rafts or micro domains. Consequently the induced\r\nby Ca2+ chelation an anisotropic cluster with interfacial boundary PC/Ca2+ PA or LPC/Ca2+ LPA is the reason of intra-molecular\r\nreconstruction of PLD resulted in its activation and activity regulation in the process of substrate exhaustive hydrolysis. Moreover it is\r\npossible to suppose that forming of growing out cluster with its specific physicochemical properties can induce similar reconstruction\r\nof other adjacent functional proteins. This enzymatic process obtains planar directivity to the side of cluster forming and thus PLD\r\nand perhaps other lipolytic enzymes which produce anisotropic clusters may be relevant to lateral vector enzymes as opposed to\r\ntransmembrane enzymes-vectors. On the other hand the newly formed clusters, rafts, domains are the mobile stocks mobilizing the\r\nimportant biologically active compounds as for example PA or LPA and Ca2+ which are the secondary messengers in case of PLD.\r\nMoreover it is possible suppose that the important constructional function (chaperoning, refolding and tuning) of lipolytic enzymes\r\nwhich appears on interface of different artificial multi-component membrane like systems will be inherent to biological membranes\r\ntoo. Bio-membranes which contain specific sets of natural lipids distributed by numerous micro domains and representing lipid\r\nmosaic structure contain a huge net of inter-domain boundaries which can be the places of reconstruction of functional proteins and\r\nperhaps other biopolymers too. The lipid-membrane protein interface may be effective in this role too.