Day 1 :
Keynote Forum
Joachim Wink
Helmholtz Centre for Infection Research,Germany
Keynote: The upcoming role of actinomycetes in the strain collection of the helmholtz centre for infection
Time : 10:00-10:45
Biography:
Joachim Wink has completed his PhD in 1985 from Frankfurt University, Germany. He has then joined Hoechst AG where he was responsible for the strain collection and specialized in the cultivation and taxonomic characterization of Actinobacteria and Myxobacteria. In 2012 he has joined the Helmholtz Centre for Infection Research in Braunschweig where he founded the working group of the strain collection with its focus on Myxobacteria. He has published more than 40 papers on secondary metabolites and the taxonomy of the producing microorganisms in reputed journals.
Abstract:
The focus of the HZI has traditionally been on myxobacteria for a long time but as actinomycetes are still today a very important and successful group for the detection and isolation of novel biological active compounds especially antibiotics,we started to incorporate a number of actinomycetes strains and projects the work of the microbial strain collection group MISG which was founded in 2013. The collection includes about 2000 reference strains of the class Actinobacteria and more than1000 new isolates of uncommon genera which have been isolated in-house or are part of external cooperation. To enhance the number of novel antibiotics we try to work with uncommon new isolates of Actinobacteria. Therefore we us neglected old isolation methods like the baiting with ceratin and also develop new methods. Besides the screening of novel actinomycetes,the potential of “old” strains is still not completely evaluated. We therefore try to induce “silent” biosynthetic gene clusters by use of different chemical and biological inducers and also look on old antibiotics which have not been developed during the “golden time” of antibiotic research. The compendium of Actinobacteria is also a taxonomic outcome of the activities of the strain collection of the HZI. The activities of the microbial strain collection of Actinobacteria within the HZI structure are shown and examples of the different aims will be given in the talk.
Keynote Forum
Patrick Fickers
University of Liege, Belgium
Keynote: Pichia process optimization by methanol/sorbitol co-feeding
Time : 10:45-11:30
Biography:
Patrick Fickers has obtained his PhD from University of Liege, Belgium in 2004. He has worked as Post-doctorate at Polytech Lille, France and as a FNRS Fellow at the Centre of Protein Engineering, Liege, Belgium. He was an Associated Professor at Unversité libre de Bruxelles and the Head of the Biotechnologyand Bioprocess Unit (2009-014). In January 2015, he has joined as a Professor the Microbial Processes and Interactions Research Unit (MiPI) at Gembloux AgroBiotech, Univerity of Liege. He has published 37 research papers in peer-reviewed journals and 6 book chapters. His researches focus on the development of yeast and bacterial strains by metabolic engineering and on process development in bioreactor for the production of valuable compounds
Abstract:
Recombinant protein production driven by AOX1 promoter is challenged by a high oxygen demand and heat production, especially in large-scale bioreactor. A promising solution relies on a methanol/sorbitol co-feeding strategy during the induction phase. In this work, transient continuous cultures were first performed to quantitatively assess the benefits of a methanol/sorbitol co-feeding process with a P. pastoris Mut+ strain bearing a pAOX1-lacZ construct served as a reporter gene. Our results demonstrated that cell-specific oxygen consumption (qO2) could be reduced by decreasing the methanol fractionin the feeding media. Optimal pAOX1 induction was achieved and maintained in the range of 0.45~0.75 C-mol/C-mol of methanol fraction. In addition, the qO2 was reduced by 30% at most in those conditions. Based on a simplified metabolic network, metabolic flux analysis (MFA) was performed to quantify intracellular metabolic flux distributions during the transient continuous cultures, which further shed light on the advantages of methanol/sorbitol co-feeding process. Secondly, chemostat cultures were performed to investigate the cell growth, metabolism and regulation of the AOX1 promoter (pAOX1) regarding co-feeding rate of optimized methanol/sorbitol mixture. Our results highlight that methanol/sorbitol co-feeding allowed cells
to adapt to oxygen transient limitation that often occur at industrial scale with reduced effect on pAOX1 induction and cell viability. The optimal feeding rate tested here was 6.6 mmolC.(DCW.h)-1 at an oxygen transfer rate (OTR) of 8.28 gO2 (l.h)-1 with over five-fold pAOX1 induction (probably directly associated with target protein productivity) compared with previous work.