Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2020
Authors
Kaare Magne Nielsen Yngvild Wasteson Siamak Pour Yazdankhah Øivind Bergh Ole Martin Eklo Erik J. Joner Elisabeth Henie Madslien Pål Trosvik Bjørnar YtrehusAbstract
No abstract has been registered
Authors
Yngvild Wasteson Hege Salvesen Blix Erik J. Joner Elisabeth Henie Madslien Jakob Ottoson Henning Sørum Wolfgang Uhl Siamak Pour Yazdankhah Øivind Bergh Ole Martin Eklo Kaare Magne Nielsen Pål TrosvikAbstract
The request from NFSA and NEA: Antimicrobial agents and microorganisms are introduced to sewage systems by different human activities, from private homes, institutions such as schools and hospitals, office buildings, industrial and commercial activities, i.e., from everywhere where people work and live. The Norwegian Food Safety Authority (NFSA) and Norwegian Environment Agency (NEA) asked the Norwegian Scientific Committee for Food and Environment (Vitenskapskomiteen for mat og miljø, VKM) for an extension of the 2009 VKM report “Risk assessment of contaminants in sewage sludge applied on Norwegian soils” regarding the impact of wastewater (WW)- and sewage sludge treatment methods used in Norway, on the fate and survival of antimicrobial resistant bacteria, fate of antimicrobial resistance genes, and main drivers for resistance (e.g. antibiotics, antifungal agents, heavy metals, disinfectants). The request addressed by VKM: VKM appointed a working group, consisting of three members of the Panel on Microbial Ecology, four external members and VKM staff to prepare a draft Opinion document. The Panel on Microbial Ecology has reviewed and revised the draft prepared by the working group and approved the Opinion document “Assessment of the impact of wastewater and sewage sludge treatment methods on antimicrobial resistance”. The antimicrobial resistance cycle: Exposure to antimicrobial agents is regarded as the most important driver for development and dissemination of AMR in microorganisms. Consequently, an important location for the development of AMR is the gut of humans or animals receiving antimicrobial drug therapy. As ARB, ARG, resistance genes and antimicrobial agents will end up in the WW system, this system could be regarded as a potential hot spot for interactions between different microorganisms, between different antimicrobial agents, and between microorganisms and antimicrobial agents. Hospitals and pharmaceutical companies are regarded as being an important source for antimicrobial drug residues released in WW. At the wastewater treatment plant (WWTP), bacteria and genes end up either in the effluent wastewater fraction or in the sludge fraction. When ARB and ARG are distributed with the WW sludge, they may reach arable land when the sludge is used as soil improver and fertilising product, and thus be recycled into the food-production chain. When following the effluent WW fraction, ARB and ARB will be released into WW recipients, such as lakes, rivers or fjords, and may, from these environments, also be recycled into food production. In each step of these cycles, ARB and ARG will be introduced into new environmental compartments to which they must adapt, and to microbial communities with which they must compete for survival and growth. Depending on the bacterial species, these new environmental compartments will be more or less hostile, but they will also provide opportunities for microbial interactions, like dissemination of ARG due to horizontal gene transfer (HGT) within and between bacterial species. Findings: It is challenging to deliver a general assessment of the nature of as well as the probability for direct discharge of ARB and ARG into effluent WW and applied sludge. This is due to the combined complexity of resistance carriers, traits, various sources of variation, and the WW systems. Moreover, there is currently a lack of harmonized methods and protocols to compare studies from different systems. However, there are no strong indications that there is a significant enrichment of ARB in WWTP operated under European conditions, which, on a general level, also applies to the Norwegian situation. Although some studies indicate a slight increase in the fraction of ARB, the absolute reduction in bacterial load during WW treatment (WWT) is significant; removal of between 99 % to 99.9 % of faecal indicator bacteria is generally achieved by secondary .......
Abstract
No abstract has been registered
Authors
Juan Hu Yuanyuan Yao Yalin Yang Chenchen Gao Fengli Zhang Rui Xia Chao Ran Zhen Zhang Jihong Liu Clarke Zhigang ZhouAbstract
Probiotics confer a health benefit on the host and could be used as a good alternative to antibiotics. Probiotics are strain‐specific when exerting their function, so it is necessary to identify them to strain level. In recent years, intra‐species molecular typing and identification methods have developed rapidly, which commonly are used for typing the main pathogenic bacteria and rare for studies on probiotic typing, whilst it is imperative. This article describes molecular typing methods including AFLP, RAPD, PFGE, ribotyping, MLST, rep‐PCR and whole‐genome sequencing to identity some aquatic probiotics approved by the Ministry of Agriculture of China, which are Bifidobacterium, Enterococcus, Lactobacillus, Pediococcus, Aspergillus, Bacillus, Rhodopseudomonas palustris and Streptococcus thermophilus. In addition, the principles, applications, advantages and disadvantages of these typing methods are also discussed.
Abstract
Diseases caused by viruses threaten the production industry and food safety of aquaculture which is a great animal protein source. Grass carp reovirus (GCRV) has caused tremendous loss, and the molecular function of viral proteins during infection needs further research, as for most aquatic viruses. In this study, interaction between GCRV major outer capsid protein VP4 and RIG-I, a critical viral RNA sensor, was screened out by GST pull-down, endogenous immunoprecipitation and subsequent LC-MS/MS, and then verified by co-IP and an advanced farred fluorescence complementation system. VP4 was proved to bind to the CARD and RD domains of RIG-I and promoted K48-linked ubiquitination of RIG-I to degrade RIG-I. VP4 reduced mRNA and promoter activities of key genes of RLR pathway and sequential IFN production. As a consequence, antiviral effectors were suppressed and GCRV replication increased, resulting in intensified cytopathic effect. Furthermore, results of transcriptome sequencing of VP4 stably expressed CIK (C. idella kidney) cells indicated that VP4 activated the MyD88-dependent TLR pathway. Knockdown of VP4 obtained opposite effects. These results collectively revealed that VP4 interacts with RIG-I to restrain interferon response and assist GCRV invasion. This study lays the foundation for anti-dsRNA virus molecular function research in teleost and provides a novel insight into the strategy of immune evasion for aquatic virus.
Authors
Rui Xia Yalin Yang Xingliang Pan Chenchen Gao Yuanyuan Yao Xuewei Liu Tsegay Teame Fengli Zhang Juan Hu Chao Ran Zhen Zhang Jihong Liu Clarke Zhigang ZhouAbstract
Quorum quenching (QQ) blocks bacterial cell-to-cell communication (i.e., quorum sensing), and is a promising antipathogenic strategy to control bacterial infection via inhibition of virulence factor expression and biofilm formation. QQ enzyme AiiO-AIO6 from Ochrobactrum sp. M231 has several excellent properties and shows biotherapeutic potential against important bacterial pathogens of aquatic species. AiiO-AIO6 can be secretory expressed in Bacillus subtilis via a non-classical secretion pathway. To improve AiiO-AIO6 production, four intracellular protease-deletion mutants of B. subtilis 1A751 were constructed by individually knocking out the intracellular protease-encoding genes (tepA, ymfH, yrrN and ywpE). The AiiO-AIO6 expression plasmid pWB-AIO6BS was transformed into the B. subtilis 1A751 and its four intracellular protease-deletion derivatives. Results showed that all recombinant intracellular protease-deletion derivatives (BSΔtepA, BSΔymfH, BSΔyrrN and BSΔywpE) had a positive impact on AiiO-AIO6 production. The highest amount of AiiO-AIO6 extracellular production of BSΔywpE in shake flask reached 1416.47 U/mL/OD600, which was about 121% higher than that of the wild-type strain. Furthermore, LC–MS/MS analysis of the degrading products of 3-oxo-C8-HSL by purification of AiiO-AIO6 indicated that AiiO-AIO6 was an AHL-lactonase which hydrolyzes the lactone ring of AHLs. Phylogenetic analysis showed that AiiO-AIO6 was classified as a member of the α/β hydrolase family with a conserved “nucleophile-acid-histidine” catalytic triad. In summary, this study showed that intracellular proteases were responsible for the reduced yields of heterologous proteins and provided an efficient strategy to enhance the extracellular production of AHL lactonase AiiO-AIO6.
Authors
Yuan-Yuan Yao Ya-Lin Yang Chen-Chen Gao Feng-Li Zhang Rui Xia Dong Li Juan Hu Chao Ran Zhen Zhang Jihong Liu Clarke Zhi-Gang ZhouAbstract
Aquaculture is a fast‐growing and rapidly expanding industry in the world. Probiotics are widely used in aquaculture and have provided benefits to aquatic animal health, and it is also a promising alternative to antibiotics for control of fish diseases. With the development of biotechnology, new expression systems and novel techniques for the surface display of heterologous proteins in surface of probiotics cells have been developed. This review provides an overview of the systems and strategies for displaying functional proteins on the surface of probiotics commonly used in aquaculture, which are Bacillus subtilis, Bacillus thuringiensis, lactic acid bacteria represented by Lactococcus lactis and yeast. Their applications in aquaculture especially for oral vaccine development afforded by this technology and prospects and challenges associated with this technology are also highlighted.
Authors
D. Vanella D.S. Intrigliolo S. Consoli G. Longo-Minnolo G. Lizzio R.C. Dumitrache E. Mateescu Johannes Deelstra J.M. Ramírez-CuestaAbstract
The reliability of short-term weather forecast provided by COSMO model in simulating reference evapotranspiration (ET0) was evaluated in 7 study sites distributed in 4 countries (Italy, Norway, Romania and Spain). The main objective of the study was to assess the optimal scenario for calculating ET0, using the FAO-56 Penman-Monteith (PM) equation, by separately considering the accuracy in the use of “past” and “forecast” data input. Firstly, each forecasted variable (air temperature, Tair; relative humidity, RH; wind speed, u2; solar radiation, Rs) and ET0 were compared with in situ observations at hourly and daily scales. Moreover the seasonality effect in the forecast performance was evaluated. Secondly, simulated ET0 were computed every three days with: (i) a “past scenario” that used the observed data input measured in situ during the previous three days, (ii) a “forecast scenario” that used the forecasted input variables for the next three days; and compared with (iii) actual ET0 obtained from the in situ measured data. A general good agreement was found between observed and forecasted agro-meteorological parameters at the different explored time-scales. The best performance was obtained for Tair and Rs, followed by RH and u2. Globally, the comparison between ET0 from the measured and forecasted data input showed high performance, with R2 and RMSE of 0.90 and 0.68 mm d−1. ET0 simulations resulted more accurate using the “forecast scenario” (1.7% overestimation), rather than using the “past scenario” (2.6% underestimation). These results open promising perspectives in the use of forecast for ET0 assessment for different agriculture practices and particularly for irrigation scheduling under water scarcity conditions.
Abstract
Dollar spot was officially documented in Scandinavia in 2013 and the spread and damage from this disease has increased during last years. In summer 2017, on the golf greens with red fescue (Vallda GC, Sweden) and with the mixture of red fescue, colonial bentgrass and annual bluegrass (Roskilde GC, Denmark) rolling 2 times per week reduced dollar spot 61% and 37% and rolling 4 times per week reduced dollar spot 95% and 54%, respectively. Thus, rolling 3-4 times per week can be recommended on golf greens with dollar spot pressure. In the experiment 2018 dollar spot was reduced 24% with increase in nitrogen from 150 to 240 kg ha-1 yr-1 on creeping bentgrass/annual bluegrass golf green (Kävlinge GK, Sweden). However, the increased N-rate lead to a higher degree Microdochium patch from 14% to 30%.
Abstract
No abstract has been registered