Day 2 :
Keynote Forum
Sergey Suchkov
I M Sechenov First Moscow State Medical University, Russia
Keynote: Principles of profiling as applicable to the infrastructure of continuous education system to impact drug design to suit an innovative model of translational pipeline
Time : 10:00-10:40
Biography:
Sergey Suchkov graduated from Astrakhan State Medical University and awarded with MD, then in 1985 maintained his PhD at the I M Sechenov Moscow Medical Academy and in 2001, maintained his Doctorship Degree at the Nat Inst of Immunology, Russia. From 1987 through 1989, he was a senior Researcher, Koltzov Inst of Developmental Biology. From 1989 through 1995, he was a Head of the Lab of Clinical Immunology, Helmholtz Eye Research Institute in Moscow. From 1995 through 2004, he was a Chair of the Dept. for Clinical Immunology, Moscow Clinical Research Institute. He has been trained at: NIH; Wills Eye Hospital, PA, USA; Univ. of Florida in Gainesville; UCSF, S-F, CA, USA; Johns Hopkins University, Baltimore, MD, USA. He was an Exe Secretary-in-Chief of the Editorial Board, Biomedical Science, an international journal published jointly by the USSR Academy of Sciences and the Royal Society of Chemistry, UK. At present, he is a Chair, Dept. for Personalized and Translational Medicine, I M Sechenov First Moscow State Medical University. He is a member of the New York Academy of Sciences, USA; American Chemical Society (ACS), USA; American Heart Association (AHA), USA; EPMA (European Association for Predictive, Preventive and Personalized Medicine), Brussels, EU; ARVO (American Association for Research in Vision and Ophthalmology); ISER (International Society for Eye Research); PMC (Personalized Medicine Coalition), Washington, USA.
Abstract:
Personalized medicine (PM) as the healthcare of the future represents an innovative model for advanced healthcare and robust platform for relevant industrial branches for diagnostics and pharmaceutics. However, rapid market penetration of new technologies demands the implementation of reforms not only in biopharma, but also in education. Therefore, the problem of the updated education of specialists in bioengineering, drug design and affiliated fields is becoming particularly urgent, and it requires significant revision of newer programs and curricula to be updated. Modernization and integration of widely accepted standards require consolidation of both the natural and medical sciences that may become the conceptual basis for the biopharma education. The main goal of this training is to provide development of novel multifaceted approaches to build academic schools for future generations. So, a higher, secondary and primary education as a trio should be integrated into the circuit. Based on current trends and own experience, we have made the first steps towards reshuffling the canonical educational tandem “School-University” and restructuring of specialized groups (with targeted disciplines) to get the mentees to be involved into having the existing healthcare system advanced and stepped forward. Moreover, non-canonical approach has been used to create a team of young researchers and biopharma students which has been recognized as The International Research Team of Youngsters under the aegis of EPMA (Brussels, EU) and ISPM (Tokyo, Japan). The integration of the primary and secondary education provides: 1. development in the chosen direction; and 2. optimization of the jointly set activity of a student and the teacher within a pair or a tandem (mentor-mentee). The above-mentioned has pre-determining value, because under the disintegration of the world community expressed the competition in quality of the scientific intellect dramatically increases. The same occurs in the areas of quality of all of three segments of the educational process, i.e., pre-college (secondary school), university and graduate.
References:
1. М Studneva, M Mandrik, Sh Song, E Tretyak, I Krasnyuk, et al. (2015) Strategic aspects of higher education reform to cultivate specialists in diagnostic and biopharma industry as applicable to predictive, preventive and personalized medicine as the medicine of the future. EPMA Journal 6(18):2-14.
2. I A Sadkovsky, O Golubnitschaja, M A Mandrik, M A Studneva, H Abe, et al. (2014) PPPM (predictive, preventive and personalized medicine) as a new model of the national and international healthcare services and thus a promising strategy to prevent a disease: from basics to practice. International Journal of Clinical Medicine 5:855-870.
3. S Suchkov, C Reading, N Rose, A Notkins, M van Herrath, et al. (2013). Translational medicine: Myth or Reality? Remedium 6:8-15.
4. T A Bodrova, D S Kostyushev, E N Antonova, Sh Slavin, D A Gnatenko, et al. (2012) Introduction into PPPM as a new paradigm of public health service: an integrative view. EPMA Journal 3(16):3-16.
Keynote Forum
Ibrahim Abdulhalim
Ben-Gurion University of the Negev, Israel
Keynote: Plasmonic biosensors on demand: tunable penetration depth, compactness, ultrahigh sensitivity and enhanced spectroscopies
Time : 10:40-11:20
Biography:
Ibrahim Abdulhalim is a Professor at the Electro-optical Engineering Unit at Ben-Gurion University of the Negev. He worked in academic institutions and companies such as the OCSC in University of Colorado Boulder, the ORC at Southampton University, the Thin Films Center of the University of Western Scotland, in KLA-Tencor, Nova and GWS Photonics. He has published over 200 articles, two books, 10 chapters and has 20 patents. He is a fellow of IoP and SPIE and an Associate Editor for the Journal of NanoPhotonics and for the Journal of Imaging.
Abstract:
Evanescent wave optical biosensors allow specific sensing by using a surface binding layer which enhances the capture of specific bio-entities within the nanoscale neighborhood to the sensor surface. However, this evanescence region is sometimes too small at the scale of few tens of nanometers which prevents obtaining monotonic signal versus concentration when the bio-entities are larger than the optical penetration depth. The purpose of this study is to describe methods for sensing both small (molecules, viruses, etc.) and large bioentities (cells, large molecules) using plasmonic sensors with tunable penetration depth. During the last few years, we have been developing different structural and system configurations for improving the performance of plasmonic biosensors based on improving the reading method and enhancing the local electromagnetic (EM) field further for the purpose of improving the sensitivity and lowering the detection limit based on SPR, SERS and SEF. The structural improvements include: (i) planar thin metal films combined with dielectric films, (ii) periodic metallic structures on planar substrate, (iii) nanosculptured thin films prepared by the glancing angle deposition technique. (iv) long range self-referenced plasmonic configurations, and lately, (v) combination of nanostructures with thin metal films for coupling of extended surface plasmons (ESP) to localized surface plasmons (LSP). The system improvements include: (i) diverging beam approach in the angular mode, (ii) polarimetric spectral mode, (iii) image and signal processing. Particularly, we have shown recently that even much higher enhancement of the EM fields is obtained by exciting the LSPs through extended surface plasmons generated on a semi-infinite metallic film surface. Biotechnology applications will be presented for sensing biomolecules and cells in water and in blood. In spite of the technological advances in optics, the need for developing molecular binding layer to improve the specificity is still in demand from the biotechnology community.
Keynote Forum
Jennifer A Littlechild
University of Exeter, UK
Keynote: Thermophilic enzymes with applications for industrial biocatalysis
Time : 11:40-12:20
Biography:
Jennifer A Littlechild is an Emeritus Professor of Biological Chemistry and has established the Henry Wellcome Centre for Biocatalysis at Exeter University in 2003. Her research studies involve the structural and mechanistic characterisation of a range of enzymes from thermophilic bacteria and archaea that have industrial applications. She has published over 200 publications in refereed high impact journals and presented her research work internationally. She has coordinated EU related project THERMOGENE and was a partner in a consortium grant HOTZYME. In UK she is funded from BBSRC and Innovate UK. These grants involve both large industrial companies and SME enterprises. She has supervised over 40 PhD students and acts as External Examiner for other PhD and Masters Students. She is the UK representative and Vice Chair of the European Section of Applied Biocatalysis and a Member of EU advisory committees for Industrial Biotechnology.
Abstract:
There is an increasing demand for new enzymes with enhanced performance and/or novel functionalities that provide savings in time, money and energy for industrial processes in the areas of high value chemical production and other white biotechnology applications. Only a small proportion of nature’s catalysts have been utilised for industrial biotechnology. The number of enzymes explored to date remains within the range of 1-2% of known biodiversity. A problem with using enzymes for industrial biocatalysis reactions is often their stability under the harsh conditions employed. The use of naturally thermostable enzymes isolated from hot environments are more stable to high temperatures, extremes of pH and exposure to organic solvents. The projects HOTZYME and THERMOGENE have identified hydrolase and transferase enzymes of industrial interest isolated from high temperature environments around the world. These have been isolated from thermophilic bacterial and archaeal genomes and metagenomes. A selection of these novel thermostable enzymes including cellulases, carboxylesterases, lactonases, epoxide hydrolases, transketolases, hydroxymethyl transferases and transaminases have been characterized both biochemically and structurally. Transaminase enzymes have received special attention for the production of chiral amines which are important building blocks for the pharmaceutical industries. These enzymes catalyse the reversible transfer of an amino group from a donor substrate onto a ketone/aldehyde or sugar acceptor molecule. They can be subdivided into 6 classes. The less studied class 4 (branched chain) (R) selective, class 5 (S) selective and class 6 (sugar) enzymes have been identified. An example of the archaeal class 4 enzyme from Archaeoglobus fulgidus; a thermostable class 5 archaeal transaminase from Sulfolobus solfataricus and class 6 sugar transaminase from A. fulgidus. Two new enzymes with interesting substrate specificity and stereo-selectivity have been discovered which have already been demonstrated at industrial scale for the production of new chiral chemical building blocks.
References:
- Littlechild J A (2017) Improving the ‘tool box’ for robust industrial enzymes. J. Industrial Microbiology and Biotechnology, 44(4-5):711–720.
- William Finnigan, Adam Thomas, Holly Cromar, Ben Gough, Radka Snajdrova, Joe Adams, Jennifer A Littlechild and Nicholas J Harmer (2017) Characterization of carboxylic acid reductases as enzymes in the toolbox for synthetic chemistry. ChemCatChem, 9:1005-1017.
- Sayer C, Finnigan W, Isupov M, Levisson M, Kengen S, van der Oost J, Harmer N and Littlechild J A (2016) Structural and biochemical characterisation of Archaeoglobus fulgidus esterase reveals a bound CoA molecule in the vicinity of the active site. Scientific Reports, 6:25542.
- Zarafeta D, Kissas D, Sayer C, Gudbergsdottir S R, Ladoukakis E, Isupov M N, Chatziioannou A, Peng X, Littlechild J A, Skretas G and Kolisis F N (2016) Discovery and characterisation of a thermostable and highly halotolerant GH5 cellulose from an Icelandic hot spring isolate. PLoS ONE 11(1):07.
Keynote Forum
Kam Bo Wong
The Chinese University of Hong Kong, China
Keynote: How urease accessory proteins coupled GTP hydrolysis/binding to nickel delivery to urease?
Time : 12:20-13:00
Biography:
Kam Bo Wong obtained his BSc and MPhil from the Chinese University of Hong Kong. He then pursued his PhD degree in the laboratory of Prof. Alan Fersht at the University of Cambridge. After Postdoctoral training in the University of Washington and University of Cambridge, he joined the Chinese University of Hong Kong in 1999, where he is now a Professor at the School of Life Sciences. His research interests are on the structure-function studies of proteins. His research group uses multi-disciplinary techniques, including protein engineering, biophysical characterization, computational methodologies, and structure determination by NMR and X-ray crystallography, to study how proteins function on the atomic and molecular levels.
Abstract:
Urease is a nickel-containing metalloenzyme that catalyzes the hydrolysis of urea into ammonia and carbon dioxide. This enzymatic reaction, which produces the acid-neutralizing ammonia, is essential for the survival of Helicobacter pylori in human stomach. In Helicobacter pylori, nickel ions delivery for urease maturation is assisted by four urease accessory proteins, UreE, UreF, UreG and UreH. Specific protein-protein interactions among these urease accessory proteins are essential for the control of binding/release of nickel along the metal delivery pathway. We have previously determined the crystal structures of UreF/UreH and GDP-bound-UreG/UreF/UreH complexes. Upon binding of UreH, the C-terminal residues of UreF are induced to form an extra helix and a loop structure stabilized by Arg-250. These conformational changes facilitate the recruitment of UreG to the UreG/UreF/UreH complex, which is essential to urease maturation. Recently, we have determined the crystal structure of the nickel/GTP-bound UreG dimer, which reveals how GTP hydrolysis induces conformational changes that induce dissociation of UreG from the UreG/UreF/UreH complex and the release of nickel to the urease.
References:
1. Fong Y H, Wong H C, Chuck C P, Chen Y W, Sun H, Wong K B (2011) Assembly of preactivation complex for urease maturation in Helicobacter pylori: crystal structure of UreF-UreH protein complex. Journal of Biological Chemistry. 286(50):43241-43249.
2. Fong Y H, Wong H C, Yuen M H, Lau P H, Chen Y W, Wong K B (2013) Structure of UreG/UreF/UreH complex reveals how urease accessory proteins facilitate maturation of Helicobacter pylori urease. PLoS Biology. 11(10):e1001678.
3. Luo F, Fong Y H, Zeng Y, Shen J, Jiang L, Wong KB (2014) How vacuolar sorting proteins interact with their cargo proteins: crystal structures of apo and cargo-bound forms of the protease-associated domain from an Arabidopsis vacuolar sorting receptor. Plant Cell. 26(9):3693-3708.
4. Lee K M, Yu C W H, Chiu T Y H, Sze K H, Shaw P C, Wong K B (2012) Solution structure of the dimerization domain of the eukaryotic stalk P1/P2 complex reveals the structural organization of eukaryotic stalk complex. Nucleic Acids Research. 40(7):3172-3182.
- Molecular Enzymology | Enzyme Therapeutics |Enzymology in drug discovery | Industrial Biotechnology | Biotechnology Applications
Location: Armstrong
Session Introduction
Mamuka Kvaratskhelia
University of Colorado School of Medicine, USA
Title: The dual role of integrase in HIV-1 replication
Biography:
Mamuka Kvaratskhelia began his independent research career at the Ohio State University in 2003 and has focused on better understanding of the structure and function of HIV-1 integrase as a therapeutic target. He has recently (2017) moved to University of Colorado Denver as a Professor of Medicine (Infectious Diseases) to further extend his studies on HIV-1 integrase. By employing innovative biochemical, biophysical, structural biology, molecular biology and virology approaches, his research team has made many important contributions to the field, which include the discovery of second, non-catalytic role of integrase in HIV-1 biology and elucidating the mode of action of ALLINIs.
Abstract:
A key HIV-1 enzyme integrase catalyzes irreversible insertion of a viral DNA copy of its RNA genome into human chromosome, which is essential for viral replication. Therefore, integrase is an important therapeutic target. Productive integration into host chromatin results in the formation of the strand transfer complex (STC) containing catalytically joined viral and target DNAs. We have used cryo-EM coupled with biochemistry and virology experiments to obtain high-resolution structures for STCs and to characterize the integrase multi-subunit assemblies into large, nucleoprotein complexes. We are currently extending these studies to elucidate structural basis for the mode of action of clinically used integrase strand transfer inhibitors (INSTIs), which bind to the enzyme active site in the context of the integrase-viral DNA complex and block the strand transfer reaction. Our parallel efforts are focused on studying allosteric HIV-1 integrase inhibitors (ALLINIs), which are currently undergoing clinical trials (2-5). Unlike INSTIs, ALLINIs bind at the integrase dimer interface and induce aberrant protein multimerization. Unexpectedly, in infected cells ALLINIs were significantly more potent during virion maturation rather than during integration. ALLINIs markedly altered virus particle morphogenesis by misplacing the ribonucleoprotein complexes outside the protective viral capsid shell and yielded inactive virions. In turn, these findings have suggested that integrase has a second function in HIV-1 biology. Our follow up studies have revealed that integrase directly binds the viral RNA genome in virions. These interactions have specificity, as integrase exhibits distinct preference for select viral RNA structural elements. ALLINIs impair integrase binding to viral RNA in virions of wild-type, but not escape mutant, virus. These results reveal an unexpected biological role of integrase binding to the viral RNA genome during virion morphogenesis and elucidate the mode of action of ALLINIs. Collectively our findings indicate that viral integrase plays a dual role during HIV-1 replication.
References
- Passos D O, Li M, Yang R, Rebensburg S V, Ghirlando R (2017) Cryo-EM structures and atomic model of the HIV-1 strand transfer complex intasome. Science. 355(6320):89-92.
- Kessl J J, Kutluay S B, Townsend D, Rebensburg S, Slaughter A et al. (2016) HIV-1 integrase binds the viral RNA genome and is essential during virion morphogenesis. Cell. 166(5):1257-1268.
- Sharma A, Slaughter A, Jena N, Feng L, Kessl J J (2014) A new class of multimerization selective inhibitors of HIV-1 integrase. PLoS Pathog. 10(5):e1004171.
- Jurado K A, Wang H, Slaughter A, Feng L, Kessl J J et al. (2013) Allosteric integrase potency is determined through the inhibition of HIV-1 particle maturation. Proc. Natl. Acad. Sci. USA. 110(21):8690-8695.
Alessandra Astegno
University of Verona, Italy
Title: Characterization of cystathionine γ-lyase from T. gondii: a target for drug development?
Biography:
Alessandra Astegno is interested in different aspects of Protein Chemistry and Enzymology, including folding, evolution and structure-function relationship of proteins and macromolecular assemblies. She is currently an Assistant Professor in Biochemistry at the Department of Biotechnology of the University of Verona. She has a solid background in recombinant protein expression and purification, functional and structural characterization of pyridoxal phosphate-dependent enzymes as well as metallo-proteins.
Abstract:
Toxoplasma gondii is a protozoan parasite of medical and veterinary relevance responsible for toxoplasmosis in humans. As there is currently no vaccine available for human, the identification of good target candidates for future drug development is urgently required. A recent proteomic analysis of partially sporulated oocysts of T. gondii showed that oocyctes have a greater capability of de novo amino acid biosynthesis, shedding light on a stage-specific subset of proteins whose functional profile is consistent with the oocyst need to resist various environmental stresses. Among these putative oocyst/sporozoite-specific proteins, three enzymes involved in cysteine metabolism, i.e., cystathionine β-synthase, cystathionine γ-lyase (CGL) and cysteine synthase, were found. However, despite the central metabolic roles of these enzymes, the functionality of none of them has so far been investigated. Herein, CGL from T. gondii (TgCGL) has been cloned, expressed and physiochemically and enzymatically characterized. The purified TgCGL is a functional enzyme which splits L-cystathionine almost exclusively at the CγS bond to yield L-cysteine. This finding likely implies that the reverse transsulfuration pathway is operative in the parasite. The enzyme displays only marginal reactivity toward L-cysteine, which is also a mixed-type inhibitor of TgCGL activity, therefore indicating a tight regulation of cysteine intracellular levels in the parasite. Structure-guided homology modelling revealed two striking amino acid differences between human and parasite CGL active sites (Glu59 and Ser340 in human to Ser77 and Asn360 in toxoplasma). Mutation of these two residues to the corresponding residues in human revealed their importance in modulating both substrate and reaction specificity of the parasitic enzyme. Our findings might have far-reaching implications for the use of TgCGL as anti-toxoplasmosis drug target.
References:
- Astegno A, Maresi E, Bertoldi M, La Verde V, Paiardini A, et al. (2017) Unique substrate specificity of ornithine aminotransferase from Toxoplasma gondii. Biochem J. 474(6):939-955.
- Astegno A, Bonza M C, Vallone R, La Verde V, D'Onofrio M, et al. (2017) Arabidopsis calmodulin-like protein CML36 is a calcium Ca2+ sensor that interacts with the plasma membrane Ca2+-ATPase isoform ACA8 and stimulates its activity. J Biol Chem. 292(36):15049-15061.
- La Verde V, Trande M, D'Onofrio M, Dominici P and Astegno A (2018) Binding of calcium and target peptide to calmodulin-like protein CML19, the centrin 2 of Arabidopsis thaliana. Int J Biol Macromol. 108:1289-1299.
- Rossignoli G, Phillips R S, Astegno A, Menegazzi M, Voltattorni CB, et al. (2018) Phosphorylation of pyridoxal 5'-phosphate enzymes: an intriguing and neglected topic. Amino Acids. 50(2):205-215.
- Allegrini A, Astegno A, La Verde V and Dominici P (2017) Characterization of C-S lyase from Lactobacillus delbrueckii subsp. bulgaricus ATCC BAA-365 and its potential role in food flavour applications. J Biochem. 161(4):349-360.
Shree Kumar Apte
Bhabha Atomic Research Centre, India
Title: Engineering cyanobacterial nitrogen bio-fertilizer for rice cultivation in stressful environment
Biography:
Shree Kumar Apte obtained his Master’s in Botany from Jiwaji University, Gwalior, India with a Gold Medal in Science Faculty in 1972. He researched at the Bhabha Atomic Research Centre (BARC), Mumbai, India for 42 year, before retiring in 2014 as a distinguished Scientist and Director of the Bioscience Group, BARC. He is an elected Fellow of all three National Science Academies and the National Agriculture Science Academy in India. Currently he serves as Emeritus Professor, Homi Bhabha National Institute, J C Bose National Fellow (DST) and Raja Ramanna Fellow (DAE) at BARC, Mumbai.
Abstract:
As a naturally abundant, photosynthetic, nitrogen-fixing microbe, the cyanobacterium Anabaena contributes significantly to the nitrogen and carbon economy of tropical soils, especially in cultivation of rice paddy. However, its nitrogen bio-fertilizer potential is adversely affected by common abiotic stresses. Engineering enhanced nitrogen fixation and stress tolerance capabilities in this microbe through genetic manipulation is seriously limited due to the unavailability of appropriate tools and techniques and knowledge of suitable candidate genes. In recent years, our laboratory has devised an electroporation protocol for genetic transformation that achieves high frequency gene transfer and overcomes problems associated with the current practice of tri-parental conjugation between E. coli strains and Anabaena. We have also constructed (a) a suitable vector for new gene discoveries, and (b) a novel integrative expression vector pFPN, placing desired genes at a defined locus in Anabaena genome and facilitates their high level expression from an eco-friendly light-inducible promoter. Using these tools we have identified several genes responsible for enhanced heterocyst formation and nitrogen fixaton (hetR), chaperones (groESL, cpn60) for protein folding and homeostasis, and several oxidative stress tolerance genes (superoxide dismutases, catalases and peroxiredoxins) which confer superior stress tolerance to Anabaena. The approach has proved very useful for constructing recombinant Anabaena strains capable of nitrogen fixation in stressful environments.
Yungui Yang
Northwest A & F University, China
Title: Infulence of four kinds of additives and concentration on oats silage effect
Biography:
Yungui Yang graduated from China Agricultural University in 1987 with a Master's degree in Grassland Science. In August of the same year, he taught at the Northwest A&F University. In 2006, he received a Doctorate in Soil Resources and Information Technology direction. Now he is a member of Lawn Professional Committee of China Grass Society and Director of Grassland Resources and Management Committee. In October 2012, he went to the United States to attend the international annual conference jointly organized by the American Society of Agricultural Sciences, the Crop Science Society and the Soil Science Society. In October 2013, he went to Mongolia to attend the Eurasian Pacific Union Symposium. He is currently a Member of Comprehensive Utilization of Straw Resources of China Agronomy, a review expert of Life Science Division of NSFC, a fellow of American Society of Agricultural Sciences, Soil Society and Crop Society.
Abstract:
Statement of the Problem: The aim for this research was to study the effect of different additives and concentration on oat silage. Selected Dancer as material was used for silage in milk stage, and four kindsof additives respectively at different concentration were used. They were lactobacillus (0 mg/kg, 1 mg/kg, 5 mg/kg, 10 mg/kg), formic acid (0 ml/kg, 1 ml/kg, 5 ml/kg, 10 ml/kg), sucrose (0%, 1%, 2%, 4%) and cellulose (0 mg/kg, 50 mg/kg, 100 mg/kg, 150 mg/kg). The materials were ensiled at room temperature and opened 60 days later, and the fermentation quality and the chemical composition were analyzed. Results showed that it had a positive impact on Dancer silage with four kinds of additives. Considering nutritional value index(crude protein, ether extract and crude fiber) When cellulase were applied at 50 mg/kg, the oats silage were excellent. Considering silage quality indexes of pH value, AN/TN, soluble sugar content and lactic acid content, sucrose at 2% level was the best concentration. The best concentration of different additives were that: lactobacillus (5 mg/kg), formic acid (5ml/kg), sucrose (2%) and the influence on silage quality have no close connection with concentration when added cellulase.
References:
- Ni K, Wang F, Zhu B, et al. (2017) Effects of lactic acid bacteria and molasses additives on the microbial community and fermentation quality of soybean silage. Bioresource Technology. 238: 706-715.
- Carvalho V V, Paulino M F, Detmann E, et al. (2017) Effects of supplements containing different additives on nutritional and productive performance of beef cattle grazing tropical grass. Tropical Animal Health and Production. 49(5): 983-988.
- Hou M, Gentu G, Liu T, et al. (2017) Silage preparation and fermentation quality of natural grasses treated with lactic acid bacteria and cellulase in meadow steppe and typical steppe. Asian-Australasian Journal of Animal Sciences. 30(6): 788.
- Ning T, Wang H, Zheng M, et al. (2017) Effects of microbial enzymes on starch and hemicellulose degradation in total mixed ration silages. Asian-Australasian Journal of Animal Sciences. 30(2): 171.
Biography:
C Gopinathan is working as an Associate Professor in the Department of Biotechnology at the University of Calicut. He has finished his MSc, MTech in Biotechnology. His specialization is towards Bioprocess Technology/Fermentation Technology. He is the former member of Academic Council, University of Calicut, American Society for Microbiology and Association of Microbiologists of India.
Abstract:
Mosquito borne diseases not only cause loss of lives but also impose heavy health and economic burdens. Extensive use of chemical insecticides for the control of malaria and other mosquito borne diseases has led to the development of resistance in mosquitoes to these insecticides and are hazardous to the environment. Biolarvicides of the strain Bacillus thuringiensis israelensis (Bti), serotype H-14 is highly effective against mosquito larvae. Even though Bti products are efficient controls for mosquito and black fly larvae, their use in developing countries is limited by their cost. Thus, there is a need to reduce the overall production cost of Bti in order to make it competitive in the market. It depends on many factors; however, the raw material cost is one of the most important criteria which may comprise >70% of the overall production cost. Fruit wastes are available in plenty and contain mainly fructose as the carbon source, which is easily fermentable and can substitute costly substrates like glucose. Channelizing huge quantities of rotten/waste pineapples which otherwise are discarded can substantially reduce production cost of Bti. Similarly fish-amino acid produced by fermenting rotten fish and jaggery/molasess has proved to be excellent as a medium supplement; especially to overproduce the much wanted delta endotoxin produced by Bti. India is one of the countries leading in fruit and vegetable production. It is also blessed with one of the longest coastline in the world of approximately 7516.6 km. The total annual catch is around 4 million metric tons. In addition it is second after Brazil in sugarcane cultivation with an annual yield of 3412 million metric tons. The massive availability of fruit wastes (pineapples) and huge quantities of rotten /discarded fish , which are freely available, all can be channelized for cost effective production of this value added product, substantially lowering the media cost of Bti production when scale- up is attempted. Results show biomass increase of up to 27% compared to control when pineapple juice was used as the main carbon source. The toxicity improvements with fish-amino acid supplemented medium, shows considerable reduction in killing time of Aedes aegypti larvae.
K V Venkatachalam
Nova Southeastern University, USA
Title: Structure/function of 3’-phosphoadenosine 5’-phosphosulfate (PAPS) synthase (PAPSS)
Biography:
K V Venkatachalam serves as the Professor of Biochemistry at Nova Southeastern University (NSU). While he was at National Institutes of Health (NIH) he cloned, expressed and characterized human PAPSS. He was the pioneer in the field of human PAPSS1 and the isoform PAPSS2b. He has performed site directed mutagenesis studies on the key residues of PAPSS. In order to obtain in silico knowledge on thermodynamics of PAPSS, he collaborates with Dr. Rudiger Ettrich of Czech Academy of Sciences. In 2015, he was honored to be part of the College of Sciences of Florida Atlantic University (FAU), Boca Raton, FL, as an Affiliate Research Professor. He is training numerous PhD and Medical Students on research in the areas of Halitosis/Periodontitis, Cancer and Bone diseases. In 2017, he was awarded a joint appointment with the College of Allopathic Medicine, headed by the Founding Dean Johannes Vieweg, MD, at NSU.
Abstract:
3’-Phosphoadenosine 5’-phosphosulfate synthase (PAPSS) catalyzes the formation of PAPS from inorganic sulfate and ATP. In the first step inorganic sulfate combines with ATP to form adenosine 5’-phosphosulfate (APS) and pyrophosphate (PPi) catalyzed by the ATP sulfurylase domain. In the second step APS kinase catalyzes the phosphorylation of APS at the 3’ hydroxyl of APS to form PAPS and ADP. PAPSS utilizes 2 moles of ATP and cleaves it differently during PAPS formation, a feature that is unique only to PAPSS. ATP sulfurylase domain cleaves the ATP at the alpha-beta position whereas the APS kinase domain splits the ATP between beta-gamma position. The alpha-beta cleavage of ATP among all ATP sulfurylases share the common motif RNPxHxxH and henceforth it is called Venk-Ettrich motif. Site directed mutagenesis and computational modeling confirms the role of HNGH residues on alpha-beta splitting of ATP. The beta-gamma splitting of ATP contains a typical Walker A motif. Further studies are underway to look at the details of the reaction mechanism. Our overall aim is to look at 1. How 3D structure of PAPSS determines the enzyme function? 2. Studying the roles of specific amino acid residues and the dynamics of it in aqueous solution. 3. Making explicit structural and thermodynamic predictions of ligand binding. 4. Understanding the structural/functional consequences of the proteins due to DNA mutations among various human populations.
Methods: Homology modelling with YASARA, ligand docking with AUTODOCK, molecular dynamics simulations in GROMACS (for at least 100ns using the AMBER99SB force field) were used. MM-PBSA calculations were performed to calculate free energies.
Conclusion & Significance: Experimental site directed mutagenesis studies of key residues on function and molecular simulation results on structure correlates very well. The overall binding energies of the mutants that exhibited less activity/no enzyme activity required higher free energy of binding for substrates.