3^rd International Conference on Enzymology and Molecular Biology March 05-06, 2018 London, UK

Biography:

Peter J F Henderson is a Professor of Biochemistry and Molecular Biology in the University of Leeds. He obtained his BSc in 1965 and PhD in 1968, both in Biochemistry, at the University of Bristol. After Postdoctoral training at the Enzyme Institute, Madison, University of Wisconsin and in the Department of Biochemistry at Leicester, he became a University Lecturer in 1973. In 1975 he moved to the Department of Biochemistry at Cambridge, where he became Reader in Molecular Biology of Membranes in 1990. He has held Visiting Professorships in Japan, Canada and Australia. He was Scientific Director of the European Membrane Protein (EMeP) consortium 2003-2008, Coordinator of the European Drug Initiative for Channels and Transporters (EDICT) 2008-2012 and held Leverhulme Trust Emeritus Research Fellowships in 2001-2002 and 2014-2017. He has published over 200 scientific papers in the fields of Membrane Transport, Enzyme Kinetics and Structural Biology.

Abstract:

The Mhp1 Na⁺-hydantoin membrane symport protein from Microbacterium liquefaciens is a paradigm for the nucleobase-cation-symport, NCS-1, family of transport proteins found widely in archaebacteria, bacteria, yeasts and plants. Their metabolic roles include the capture by cells of nitrogen compounds and vitamins from the environment. Mhp1 is also a structural model for the huge range of ‘5-helix-inverted-repeat’ superfamily of proteins, because, unusually, crystal structures are available for its open-outwards, occluded, and open-inward conformations. Here we accomplish a detailed dynamic model of the partial reactions in an alternating access cycle of membrane transport derived from substrate binding studies to the purified Mhp1 protein by combining novel mass spectrometry, stopped-flow and steady state kinetic analyses and mutagenesis. The mechanism of coupling substrate transport to the Na⁺-gradient is revealed during a sequence of mostly reversible kinetic steps that explain how transfer of substrate across the membrane is affected by changes in conformational states. The AceI H⁺/substrate antiport protein from Acinetobacter baumannii is a paradigm for the proteobacterial antimicrobial compound efflux (PACE) family of drug efflux proteins found dispersed throughout the Proteobacteria. AceI contributes to the resistance of Acinetobacter baumannii towards the widely used antiseptic, chlorhexidine. Currently there is little structural information about the PACE family of transport proteins, but progress towards understanding the recognition of substrates and cations by AceI and its homologues will be discussed.

Biography:

Magali Remaud Simeon is Professor at the National Institute of Applied Sciences of Toulouse and is head of the Catalysis and Enzyme Molecular Engineering group of the “Laboratoire d’Ingénierie des Système Biologiques and Procédé (LISBP). She received her PhD in Biochemistry from the University of Toulouse and was Post-Doc at the University of Pennsylvania. She has co-authored more than 150 papers and is co-inventor of 22 patents.  Her research activities focus on Enzyme Engineering for white biotechnology, green chemistry, health, food/feed industries and synthetic biology. They cover enzyme structure/activity relationship studies, kinetic resolution, evolution combining both rational and combinatorial approaches, and applications to the synthesis of glycans, glycoconjugates and various synthons of interest. Her work is currently focused on the search and generation of enzymes displaying new specificities and improved catalytic properties. Her objective is to open new trajectories for biomass transformation. To this end, she specifically targets the integration of tailored enzymes in chemo-enzymatic cascades, new metabolic pathways or enzyme-based processes.

 

 

 

Abstract:

The exploration of the natural diversity, through data mining, functional genomics and/or metagenomics is an efficient mean to discover enzymes showing new functions or improved performances. These approaches can be further completed or run in parallel with semi-rational protein engineering based on structure/function studies or directed molecular evolution inspired from nature. Which of these alternatives are the best ones, in terms of effort, rapidity and efficiency? This is an open question to which a definite answer can be hardly formulated a priori. For illustration, we will take a few examples from our most recent work on glucansucrases from GH13 and GH70 families. These enzymes are naturally very efficient transglucosylases. They use sucrose as substrate and catalyze polymerization of its glucosyl units as a main reaction. Depending on their specificity, structures varying in size as well as in glycosidic linkage types can be obtained, thus giving access to an interesting panel of biopolymers. A campaign of genome sequencing and data mining allowed the isolation of atypical enzymes with new product specificities. In particular, a hyper efficient polymerase producing a gel-like polymer and, in contrast an enzyme synthesizing directly from sucrose a polymer of well-controlled low molar mass could be characterized. Structure-function studies combined with mutagenesis assays allowed us to decipher some of the molecular mechanisms behind the control of the polymer size and enzyme processivity. Another key property of these catalysts is coming from their ability to glucosylate a broad spectrum of hydroxylated molecules. Computational protein design, structurally-guided engineering and also random approaches such as neutral evolution was implemented for a fine tuning of their acceptor specificity toward non-natural acceptors such chemically protected disaccharides for vaccinal applications, polyol, flavonoids, or various chemicals. These various approaches will be described and discussed with regard to the engineering objectives.

Biography:

Catalytic Abs (catAbs) are multivalent immunoglobulins (Igs) with a capacity to hydrolyze the antigenic (Ag) substrate. In this sense, proteolytic Abs (Ab-proteases) represents Abs to provide proteolytic effects. Abs against myelin basic protein/MBP with proteolytic activity exhibiting sequence-specific cleavage of MBP is of great value to monitor demyelination whilst in multiple sclerosis. The activity of Ab-proteases was first registered at the subclinical stages, 1-2 years prior to the clinical illness and the activity of the Ab-proteases revealed significant correlation with scales of demyelination and the disability of the patients as well. So, the activity of Ab-proteases and its dynamics tested would confirm a high subclinical and predictive (translational) value of the tools as applicable for personalized monitoring protocols. Ab-proteases directly affecting remodeling of tissues with multilevel architectonics (for instance, myelin) are of tremendous value. By changing sequence specificity one may reach reduction of a density of the negative proteolytic effects within the myelin sheath and thus minimizing scales of demyelination. Ab-proteases can be programmed and re-programmed to suit the needs of the body metabolism or could be designed for the development of new catalysts with no natural counterparts. Further studies are needed to secure artificial or edited Ab-proteases as translational tools of the newest generation to diagnose, to monitor, to control and to treat and rehabilitate multiple sclerosis patients at clinical stages and to prevent the disorder at subclinical stages in persons at risks.

Abstract:

Catalytic Abs (catAbs) are multivalent immunoglobulins (Igs) with a capacity to hydrolyze the antigenic (Ag) substrate. In this sense, proteolytic Abs (Ab-proteases) represents Abs to provide proteolytic effects. Abs against myelin basic protein/MBP with proteolytic activity exhibiting sequence-specific cleavage of MBP is of great value to monitor demyelination whilst in multiple sclerosis. The activity of Ab-proteases was first registered at the subclinical stages, 1-2 years prior to the clinical illness and the activity of the Ab-proteases revealed significant correlation with scales of demyelination and the disability of the patients as well. So, the activity of Ab-proteases and its dynamics tested would confirm a high subclinical and predictive (translational) value of the tools as applicable for personalized monitoring protocols. Ab-proteases directly affecting remodeling of tissues with multilevel architectonics (for instance, myelin) are of tremendous value. By changing sequence specificity one may reach reduction of a density of the negative proteolytic effects within the myelin sheath and thus minimizing scales of demyelination. Ab-proteases can be programmed and re-programmed to suit the needs of the body metabolism or could be designed for the development of new catalysts with no natural counterparts. Further studies are needed to secure artificial or edited Ab-proteases as translational tools of the newest generation to diagnose, to monitor, to control and to treat and rehabilitate multiple sclerosis patients at clinical stages and to prevent the disorder at subclinical stages in persons at risks.

 

References:

 

1.     Gabibov A A, Paltsev M A and Suchkov S V (2011) Antibody-associated proteolysis in surveillance of autoimmune demyelination: clinical and preclinical issues. Future Neurology 6(3):303-305.

2.   D Kostyushev, I Tsarev, D Gnatenko, M Paltsev and S Suchkov (2011) Myelin-associated serological targets as applicable to diagnostic tools to be used at the preclinical and transient stages of multiple sclerosis progression. Open J Immunology 1(3):80-86.

3.     Gabibov A G, Ponomarenko N A, Tretyak E B, Paltsev M A and Suchkov S V (2006) Catalytic autoantibodies in clinical autoimmunity and modern medicine. Autoimmunity Reviews 2006(5):324-330.

4.    Ponomarenko N A, Durova O M, Vorobiev I I, Belogurov A A, Telegin G B, et al. (2005) Catalytic activity of autoantibodies toward myelin basic protein correlates with the scores on the multiple sclerosis expanded disability status scale. Immunol. Lett. 103(1):45-50.

5.     Ponomarenko N A, Durova O M, Vorobiev I I, Aleksandrova E S, Telegin G B, et al. (2002) Catalytic antibodies in clinical and experimental pathology: human and mouse models. Journal of Immunological Methods 2002(269):197-211.

Biography:

David Rabuka received a PhD in Chemistry at the University of California, Berkeley as a Chevron Fellow in the Lab of Carolyn Bertozzi. His research included developing and applying the SMARTag^TM platform technology to cell surface modification. Prior to joining Bertozzi’s lab, he worked at the Burnham Institute synthesizing complex glycans followed by Optimer Pharmaceuticals, where he focused on the development of glycan and macrolide based antibiotics. He was CSO, President and Co-founder of Redwood Bioscience, where he developed novel protein conjugation methods and biotherapeutic applications such as antibody-drug conjugates. Redwood Bioscience was acquired by Catalent Pharma Solutions in Oct 2014, where he has continued to apply the SMARTag^TM technology with various collaborators and partners as a Global Head of R&D. He graduated with a Double Honors BS in Chemistry and Biochemistry from the University of Saskatchewan, where he received the Dean’s Science Award, and holds an MS in Chemistry From the University of Alberta. He has authored over 45 major publications, as well as numerous book chapters and holds over 30 patents.

Abstract:

We have developed the SMARTag^TM technology platform, which enables precise, programmable, site-selective chemical protein modification. Leveraging the target sequence of formylglycine generating enzyme (FGE), we chemoenzymatically modify proteins to generate a precisely placed aldehyde functionality that can be chemically elaborated. Subsequently, novel ligation chemistry is employed that exploits this “aldehyde tag” site. We will present recent data on our novel protein modification platform and its application to generating novel bioconjugates, including ADCs, utilizing our new conjugation chemistries and linkers. The application of these chemistries to generate site-specifically modified bioconjugates with improved efficacy and safety profiles will be presented. Additionally, we will highlight the progress in developing conjugates with a focus on preclinical studies as well as highlight our progress in cell line development and manufacturing by using this chemoenzymatic approach.