Day 2 :
Keynote Forum
Patrick Fickers
University of Liège, Belgium
Keynote: LIP2 promoter as a tool for high yield recombinants protein production in the yeast Yarrowia lipolytica
Time : 09:20-10:00
Biography:
Patrick Fickers has completed a PhD in Biochemistry from University of Liège (Belgium). After a Post-doc at Polytech’Lille (France), he joined in 2005, the Centre of Protein Engineering (Liège, Belgium) as an FNRS Fellow. From 2009 until 2014, he was an Associated Professor at Université libre de Bruxelles and the Head of the Biotechnology and Bioprocess Unit. Since 2015, he is a Professor at Gembloux Agro BioTech, University of Liege, in the Microbial Processes. He has published more than 49 research papers in peer-reviewed journals, six book chapters and three patents. His researches focus on the development of yeast strains by metabolic engineering and on process development in bioreactor for the production of compounds of biotechnological interest.
Abstract:
Non-conventional yeasts such as Y. lipolytica are considered as new cell factories for the production of recombinant proteins either at lab or industrial scale. Despite dozens of recombinant proteins have been successfully produced in this yeast, only a few expression vectors based on regulated promoters have been developed so far. Among them, promoters of key genes, namely LIP2 and POX2, of Yarrowia’s unique hydrophobic substrates metabolism have been particularly considered. Despite they are even used at industrial scale, their fine regulation is not fully understood yet. Therefore, the characterization of their regulation in regards to cell physiology, and more interestingly in function of carbon metabolism, has been the focus of this work. Our methodology was based on gene expression profiling by mean of a DsRED-reporter system or by qPCR in regard to the carbon source of the culture medium (i.e. glucose, glycerol, oleic acid, alone or in combination). For co-substrate cultures, population heterogeneity was also investigated by flow cytometry at the level carbon source uptake and intracellular lipid accumulation. Our observations have highlighted that Y. lipolytica is able to consume simultaneously glucose and oleic acid and that cell population heterogeneity is more related to a continuum of different phenotypes of cells co-consuming both carbon sources rather than having two separate sub-populations leading to producing and non-producing phenotypes. Moreover, expression of pLIP2 driven genes were more than ten-fold increase in medium containing glucose and oleic acid compared to pure hydrophobic substrate based medium.
Keynote Forum
Shin-ichi Kayano
Kio University, Japan
Keynote: Antioxidant potential in non-extractable fractions of dried persimmon (Diospyros kaki Thunb.)
Time : 10:00-10:40
Biography:
Shin-ichi Kayano graduated from the Department of Food Science and Nutrition, Faculty of Human Life Science, Osaka City University, Japan, in 1985. He worked as a Senior Researcher of research institute, Miki Corporation, Japan, from 1985 through 2004. His job in Miki Corporation was the development of new products of functional foods, and study on functional components in fruits and vegetables. He was awarded a PhD in Science in 2004, from Osaka City University, Japan, under the supervision of Professor Nobuji Nakatani. He joined the Kio University as a Professor in 2009. His current study is on the antioxidative, antimutagenic, and estrogenic ingredients in various fruits and vegetables, and the elucidation of chemical structures and action mechanism of these compounds.
Abstract:
Dried fruits of persimmon (Diospyros kaki Thunb.) are a traditional food in Japan and contain large quantities of tannins. In this study, we investigated the in vitro and in vivo antioxidant potentials of non-extractable fractions from dried persimmons. Hydrolysed non-extractable fractions showed the highest antioxidant activities in vitro. In subsequent experiments, the plasma oxygen radical absorbance capacity (ORAC) values in rats supplemented with 5% non-extractable fraction were approximately 1.5 times higher than those in control rats after 1 week in vivo. Furthermore, using an in vitro model of the gastrointestinal tract, the ORAC values of the non-extractable fraction were significantly increased with colonic fermentation in the large bowel stage. These data indicate that non-extractable fractions may possess significant antioxidant potential in vitro and in vivo.
- Microbial Ecology | Bacterial Physiology | Industrial Microbiology
Location: Consulate
Chair
Patrick Fickers
University of Liège, Belgium
Co-Chair
Shin-ichi Kayano
Kio University, Japan
Session Introduction
Adriana Giongo
Institute of Petroleum and Natural Resources, Brazil
Title: Archaeal communities from deep-sea sediment in a chemosynthetic biotic community in the south western Atlantic Ocean
Biography:
Adriana Giongo coordinates the Geobiology Lab at the Institute of Petroleum and Natural Resources in Brazil. During her MSc and PhD, she has worked with Soil Nitrogen Fixation. For the past 10 years, she has focused in Microbial Ecology from deep-sea samples, using high throughput sequencing to describe microbial communities and the role of microorganism in the carbon and nitrogen cycles.
Abstract:
Cold seep areas are widespread around the world’s oceans, occurring at different latitudes and depths. Chemosynthesis often occurs in these areas, supporting biotic communities sustained by gases such as methane, generally at temperatures of ~2º - 4ºC. Such environments have been studied in the Northern Atlantic and Pacific Oceans; equivalent systems in the Southern Hemisphere have received little attention. We have previously documented a chemosynthetic benthic community in a cold seep pockmark site in the southwestern Atlantic Ocean using clone-based phylogenetic approaches. Here we assessed the archaeal communities from samples inside a pockmark, at the seafloor level and 1 m below the seafloor using high throughput DNA sequencing. After trimming off 16S rRNA sequences shorter than 100 bp and with low quality scores, a total of 510,321 sequences were used in the downstream analysis. The most abundant archaeal phylum was Euryarchaeota representing more than 31% and 34% of the total prokaryotic sequences at the seafloor and 1 m below the seafloor, respectively. From this phylum, OTUs from ANME-1, ANME-2c and ANME-2a-2b groups were the most abundant in these samples. The Marine Benthic Group B (MBGB) belonging to the phylum Crenarchaeota was also observed in abundance in samples, representing an average of 1.65% of the total sequences at the seafloor and 0.26% at 1 m below the seafloor. Our data brings the first report based on metabarcoding analyses on the archaeal diversity of southwestern Atlantic chemosynthetic zone. In some aspects they presented interesting similarities in relation to previous microbiodiversity reports from other oceanic regions, but also it brings new venues for the in-depth
comparative analysis of these communities, from ecological and evolutionary standpoints.
Ruud A Weusthuis
Wageningen University & Research, The Netherlands
Title: Monascus ruber as cell factory for lactic acid production at low pH
Biography:
Ruud A Weusthuis obtained his PhD in Microbial Biotechnology at the Delft University of Technology (1989-1994) after studying Biology in Groningen (1984-1989). Then he joined the WUR and headed the Bioconversion Group (2004-2008). In 2007, he started working at the Wageningen University, and is active as Associate Professor of Microbial Biotechnology. He focuses on the efficient production of chemicals by microorganisms.
Abstract:
A Monascus ruber strain was isolated that was able to grow on mineral medium at high sugar concentrations and 175 g/l lactic acid at pH 2.8. Its genome and transcriptomes were sequenced and annotated. Genes encoding lactate dehydrogenase (LDH) were introduced to accomplish lactic acid production and two genes encoding pyruvate decarboxylase (PDC) were knocked out to subdue ethanol formation. The strain preferred lactic acid to glucose as carbon source, which hampered glucose consumption and therefore also lactic acid production. Lactic acid consumption was stopped by knocking out 4 cytochrome-dependent LDH (CLDH) genes, and evolutionary engineering was used to increase the glucose consumption rate (figure 1). Application of this strain in a fed-batch fermentation resulted in a maximum lactic acid titer of 190 g/l at pH 3.8 and 129 g/l at pH 2.8, respectively 1.7 and 2.2 times higher than reported in literature before. Yield and productivity were on par with the best strains described in literature so far.
Aleksander J Kruisa
Wageningen University & Research, Netherlands
Title: Ethyl acetate production by the elusive alcohol acetyl transferase from yeast
Biography:
Aleksander J Kruisa is associated with Wageningen University, The Netherlands. He started working at the Wageningen University, and is an active Professor of Microbial Biotechnology. He focuses on the efficient production of chemicals by microorganisms.
Abstract:
Ethyl acetate is an industrially relevant ester that is currently produced exclusively through unsustainable processes. Many yeasts are able to produce ethyl acetate, but the main responsible enzyme has remained elusive, hampering the engineering of novel production strains. Here we describe the discovery of a new enzyme (Eat1) from the yeast Wickerhamomyces anomalus that resulted in high ethyl acetate production when expressed in Saccharomyces cerevisiae and Escherichia coli. Purified Eat1 showed alcohol acetyltransferase activity with ethanol and acetyl-CoA. Homologs of Eat1 are responsible for most ethyl acetate synthesis in known ethyl acetate-producing yeasts, including S. cerevisiae, and are only distantly related to known alcohol acetyltransferases. Eat1 is therefore proposed to compose a novel alcohol acetyltransferase family within the α/β hydrolase superfamily. The discovery of this novel enzyme family is a crucial step towards the development of biobased ethyl acetate production and will also help in selecting improved S. cerevisiae brewing strains.
Hajar Pasha
Babol University of Medical Sciences, Iran
Title: Antifungal effect of lavender essential oil (Lavandula angustifolia) and clotrimazole on Candida albicans: an in vitro study
Biography:
Hajar Pasha is associated with Babol University of Medical Sciences, Iran . Hajar Pasha has published several papers in reputed journals. Hajar Pasha is committed to highest standards of excellence and it proves through the authorship of many books. Hajar Pasha research interests include Microbiology.
Abstract:
Introduction: The treatment of candidiasis infections is an important problem in the health care system. This study aimed to investigate the in vitro effect of lavender essential oil and clotrimazole on isolated C. albicans from vaginal candidiasis.
Materials and Methods: In this clinical trial, C. albicans isolated from the vaginal discharge samples was obtained.
Results: The pairwise comparison showed that lavender and clotrimazole had a significant difference; this difference in the lavender group was lower than clotrimazole. But, after 48 hours, there was no difference seen between groups. There was a significant difference between clotrimazole and DMSO groups. Comparing the changes between groups based on the same dilution, at 24 h and 48 h in clotrimazole group, showed a significant difference two times in the fungal cell count that its average during 48 h was less than 24 h. A significant difference was observed between the two periods in lavender group, only at the dilutions of 1/20 and 1/80. The average fungal cell count after 48 h was also lower in lavender group.
Conclusions: Given that the lavender has antifungal activity, this can be used as an antifungal agent. However, more clinical studies are necessary to validate its use in candida infection.
Keyword: candidia albicans, antifungal agent, Lavandula angustifolia
Elgabry
National Research Center, Egypt
Title: Evaluation of cellular immune response of four vaccine against caseous lymphadenitis (CLA) by lymphocyte proliferation assay (LPA):
Biography:
Dr Gabery has his expertise in Advanced Detection of Staphylococcus aureus, Enterotoxins in Milk and Staphylococcal Isolates Obtained From Retail Pork Byproducts .detection of of zoonotic Campylobacter jejuni in fast meal meat, grill chickens also he has expertise in evaluation and Preparation of Recombinant Vaccines especially against oedematous skin disease in buffalo and Caseous Lymphadenitis (CLA) in sheep ,for the first time at Egypt I can overcome oedematous skin disease in buffalo with recombinant vaccine that give protection for buffalo y about 90% protection that help improving the health of buffalo in Egypt . he also have great experience in detection the virulence gene of Campylobacter Species , S. aureus and Corynebacterium pseudotuberculosis
Abstract:
All strains of Corynebacterium pseudotuberculosis have two virulence factors ,the first is an exotoxin virulence factor called phospholipase D that increasing vascular permeability and enhances dissemination of the bacteria by damaging endothelial cells .The second virulence factor is an external lipid coat that protect the bacteria from hydrolytic enzymes in host phagocytes where the bacteria replicate and release when rupture . The ongoing process of bacterial replication, followed by attraction and inducing an inflammatory response , increasing the vascular permeability and lymph flow ,forms the characteristic abscesses associated with CL .The objective of the present study was directed to perform a comparative study for the protective efficacy of cell mediated immune response by lymphocyte proliferation assay (LPA) for different vaccine formulation to evoke protection against caseous lymphadenitis in sheep . The protective efficacy of four formulated vaccines against Corynebacterium pseudotuberculosis biotype 1 was tested on 15 male local sheep bread (Balady) from a herd free from caseous lymphadenitis Disease. Using a virulent strain of C. pseudotuberculosis biotype 1 (nitrate negative), locally isolated from severely infected sheep with caseous lymphadenitis. The animals were divided into 5 groups each of 3 animals. each one group was immunized with combined vaccine , the first vaccine composed of Toxoid PLD vaccine ,second vaccine composed of with Toxoid PLD with Bacterine (formaline killed bacteria) vaccine ,third vaccine composed of toxoid PLD plus Covaccine 8 ,fourth vaccine composed of toxoid PLD plus polyvalent clostridial vaccine locally produced and control groups of unvaccinated animals. All groups were challenged by 4 ×106 CFU forming unit per ml of live virulent strain of Corynebacterium pseudotuberculosis isolated from local sheep infected with caseous lymphadenitis. Unvaccinated animals showed manifestations of caseous lymphadenitis (CLA) that Cleary observed in naturally diseased animals. The proliferation response of lymphocytes to PLD antigen were measured at 4 weeks after challenge by lymphocyte proliferation assay (LPA)using ELISA Brdu (colorimetric) kit. The results of this work revealed that PLD toxoid could evoke cell mediated immunity measured by lymphocyte proliferation assay showing the highest stimulation index (9.12%).On the other hand combined PLD toxoid and clostridial toxoid vaccine either locally prepared clostridial vaccine (polyvalent clostridial vaccine ) or imported one (Covaccine 8)could provide protection against C. pseudotuberculosis challenge but less than that provided by vaccination with PLD alone as lymphocyte proliferation activity decreased from SI 9.12 in vaccinated sheep with single PLD toxoid vaccine to SI 5.73 in case of combined vaccine. The present study indicated that the toxoid PLD alone vaccine is most efficient vaccine was provided in animals against CLA.
Solomon Taye
University of Gondar, Ethiopia
Title: The Role of Adenylate Cyclase Toxin during Bordetella Infection
Biography:
Solomon Taye has an expertise in the field of Medical Microbiology, Immunology and parasitology. He is a lecturer at Wachemo University which is found in South Ethiopia. Besides academic activities he is conducting researches which benefit the surrounding community in Ethiopia and the global scientific community in general. His research scope is wide ranging from host-pathogen interaction to microbial cell signaling. He has an enormous interest to understand immune evasion mechanisms of pathogenic microbes which in turn boosts our knowledge to formulate the best drug and laboratory diagnostic approach. Currently, he is working on the Burden of pertussis in Ethiopia.
Abstract:
Pertussis or whooping cough is an acute respiratory disease resulting from mainly Bordetella pertussis infection. Pertussis is characterized by a ‘whooping’ sound when the person breathes in. It remains a significant cause of morbidity and mortality worldwide. Despite the availability of effective vaccines in preventing infection by B. pertussis, an estimated 50 million cases occur each year, resulting in 295,000 deaths. The majority of these cases occur in developing countries, where malnutrition and limited supportive care contribute to the case fatality rate in infants. B. pertussis possesses type I and type III secretory system to translocate its effector proteins, where they act on diverse host cell pathways and outer membrane proteins. These effector factors of B. pertussis are; filamentous hemagglutinin, fimbriae, pertussis toxin, adenylate cyclase toxin, pertactin, dermonecrotic toxin, tracheal cytotoxin and endotoxin. Adenylate cyclase is an important invasive toxin secreted by B. pertussis by a type I secretion ‘channel-tunnel’ mechanism formed by the CyaBDE proteins. Adenylate cyclase is a member of the repeat in toxin family of bacterial pore-forming toxins. Adenylate Cyclase binds host myeloid phagocytic cells expressing alpha-M2 integrin receptor (CD11b/CD18, CR3 or Mac-1), such as macrophages, neutrophils and dendritic cells. Adenylate cyclase inhibits phagocytosis, inactivates GTPase RhoA, hemolyze erythrocytes, regulates electrolyte-binding proteins, used as delivery vectors for internalization of immunogenic epitopes and possible vaccine.