2017-18 Manna Food Security Fellows
The Manna Center Program for Food Safety & Security is pleased to announce its 2017-18 Food Security Fellows for research related to issues of Food Safety and Security. We wish you the best of luck with producing important new knowledge in the field!
The Humanitarian Pickup and Distribution Problem
In recent years, food rescue has become increasingly prevalent in many countries as a means of battling food insecurity. In the course of this operation, perishable products are collected from suppliers in the food industry who are willing to donate it, and then distributed to welfare agencies which serve individuals in need. Notable reasons for the pervasiveness of this phenomenon are the sharp rise in demand for nutritional aid; the growing awareness of suppliers to the benefits they may receive from donating these products; and the growing governmental efforts to encourage such endeavors.
The problem we study focuses on the daily logistic challenges of a food bank, and is inspired by the real-life activity of the Israeli aid organization Latet. The food bank needs to simultaneously determine vehicle routes of limited duration, and allocations of food for each agency that is visited.
Our initial study has focused on a basic variant of the problem, where supply sizes are known in advance, and assuming a single product is distributed using a single vehicle for a single period. For this setting, we have designed an objective function which balances the effectiveness, defined as distributing as much food as possible; with the equity in the allocation of this food among the different agencies. We have shown that this innovative objective function satisfies desired properties of the allocation, while overcoming some of the deficiencies of other measures previously suggested in the literature. We have also developed efficient solution methods for this problem.
Developments of novel acellular Brucella species conjugate vaccine
Vaccination has proven to be an effective measure against infectious diseases, to combat with zoonotic disease live attenuated vaccines had been deployed with risk of zoonosis. Brucellosis is a zoonotic disease caused by Brucella species. These Bacteria infect land and marine mammals, establishing zoonosis in humans. Brucella species causes abortion storms which establish a key mechanism by which Brucella spread in nature with aborted placenta and fetus membranes. Transmission to humans occurs via contact with infected animal and the consumption of unpasteurized milk and milk products, aerosol transmission has been found as a contagious route of transmission in nature and makes category B Bioweapon. Brucellosis causes sterility, malaise, hepatosplenomegaly, lymphadenopathy, osteoarticular problem, epididymoorchitis, neurobrucellosis, spondlyitis, liver abscesses and endocartis. Virulence factors associated with infection are BvrR/BvrS system which controls polycation resistance, outer membrane proteins, cell invasion and intracellular replication. Vir B cascade is an additional virulence factor that assists in intracellular survival following trafficking to the site of replication. The lipopolysaccharide molecule is a surface antigen in Gram negative bacteria that includes an O-chain polymer at the hydrophilic part of the cell membrane. Several functions have been attributed to this molecule, including cell protection against extracellular penetrating molecules and involvement with host innate immune response. Passive transfer experiments suggest that antibody to Brucella O-polysaccharide possibly contribute to protection via development of B cell and Th1 driven immune response. Here we explored the O –Ps from the LPS with aim to characterize the O – Ps and develop O – Ps conjugate with Chicken Serum albumin and use conjugate as vaccine.
Unravelling Important Domestication-Related Traits in Tetraploid Wheat
One of the most useful genomic tools for plant breeding and improvement is genome sequencing. We have recently accomplished the full genome sequence of both wild emmer and durum wheat, the parents of a mapping population of 137F9 RILs. My work focus on two majorly important domestication-related traits:
1. Seed dormancy: In wild emmer wheat, only one of the two grains in a spikelet germinates during the first rainy season following maturation. This within-plant variation in seed dormancy is associated with both grain dimension differences and position within the spikelet. I found a major locus on chromosome arm 4BL that explains >40% of the observed variation between wild and domesticated wheat in terms of differential grain dimensions and seed dormancy within spikelets. The domesticated variant of this novel locus on chromosome 4B favors spikelets with equal grain size and uniform germination.
2. Wild wheat possess a natural dispersal mechanisms of brittle rachis, enables the disarticulation and scattering of spikelets upon maturity. A primary component of the domestication syndrome was the acquisition of a non-brittle rachis (Br) trait. I have developed genetic markers for the genes responsible for rachis brittleness in wheat using the recently-published sequences of the two barley orthologous genes. After genotyping a large panel of domesticated and wild wheat I suspect that in wheat the Br story is more complex and there are additional effects on this trait (data is in preparation for publication).
In the coming year(s) I intend to focus on these two traits and with the new genomic tools we now have I believe I can get deeper resolution of the related genes and their function. This knowledge is of major importance in breeding programs aiming to utilize wild relatives to improve modern cultivars.
Using scarce water efficiently on large scales: Can Centralized Irrigation Projects Make a Comeback?
Rothler's academic work evaluates an ambitious, potentially groundbreaking irrigation project in the state of Karnataka, India, called the Ramthal project. The project has recently started to provide a reliable supply of irrigation water through fully modernized drip irrigation infrastructure to 12,000 rain-fed cereal-growing farmers spread over 25,000 hectares of land. The Ramthal project also provides local smallholders with trainings by expert agronomists; and organizes farmers into water-user-associations that will be in charge of water pricing and maintenance once the implementers of the project (Jain Irrigation and Netafim) step down.
The Ramthal project has the potential of transforming agricultural development policy in India while shifting thousands of smallholder farmers from seasonal, rain-fed cereal cultivation, mostly for subsistence, to year-long, diversified market oriented cultivation. However, the project will also introduce new types of economic challenges. One challenge is the high costs involved. To justify the investment, farmers will need to realize very large gains in income and productivity; and learn to use the technology effectively. They will also have to work together in groups in order to repair the system when needed, and pay their water bills. These are difficult challenges, but if the project is successful, it will have strong implications on similar investments being considered by other Indian state government and international donors. For this reason, Rothler's evaluation of the project is important from both a research and policy perspectives.
The role of marine protected networks in fisheries sustainability faced with climate change and invasive species
Marine ecosystems are experiencing accelerating fish population declines caused by unsustainable fishing, with negative consequences to food security worldwide. In the Mediterranean Sea, in addition to overfishing, marine communities are heavily affected by the invasion of non-indigenous species, which alter the catch of commercial fish. An additional stressor to fish populations is climate-change related increases in sea temperatures, already causing distribution shifts and population declines. Facing these multiple stressors, there is an urgent need to establish measures that will guarantee sustainable fisheries catch needed for a growing human population.
Marine protected areas (MPA) have been shown to significantly increase fish population density and biomass. As protected stocks build up, reserves are predicted to supply local fisheries through density-dependent spillover of juveniles and adults into fishing grounds. But though MPA’s are well known for tempering threats of overfishing, today managers must also address climate-change and invasion impacts that can adversely affect marine environments.
My research goals are to investigate the role of MPA’s on increasing sustainable fishing across the Mediterranean Sea. Specifically, I will examine whether MPA’s provide a buffer to the spread of invasive species and modify climate related shifts in species distribution. The results will be used to understand future consequences of climate-change and invasive on fish biomass and diversity and hence future fisheries production. This study will thus provide new information about the role of MPA’s in rebuilding fish stocks and will help managers protect marine biodiversity and associated ecosystem services to ensure long-term human food security.
Soil organic matter (SOM) plays a key role in the soil quality and fertility. Remote sensing is one of the tools that shade light on the spatial dynamic distribution of the SOM under global domain. Currently, there is a growing demand for higher resolution, and more accurate spatial information of SOM in agricultural and environmental management. Nonetheless, SOM content often varies according to cropping systems and climatic conditions. Sustainable soil utilization, management and protection of the environment require a more precise understanding of the SOM stage and its spatial variability. The hypothesis of this research postulates that in order to estimate SOM, it is necessary to investigate SOM of different sources as they should not behave the same in the soil medium. The different sources of organic matter are chemically diverse, and the chemical composition of organic matter is varied from one source to another based on the origin of the SOM and on its aging cycle. Accordingly, this research will provide precise spectral analyses of different SOM and study the prediction power of spectral measurement to discriminate between the diverse SOM. To that end we assume that not only organic carbon is important but also nitrogen and particularly the C:N ratio, is the most important factor to assess SOM content and ageing stage. In this study we thus will measure the reflectance response of several SOM in a selected soil medium and track after both the quantity and quality of the SOM in the soil. The idea is to derive a spectral model to each of the system and to examine if a robust model where all SOMs involved is reliable. The spectral measurements will be carried out in simulated environment under optimal conditions, by using an ASD FieldSpec® (model FSP 350-2500P) spectrometer connected to SoilPRO (Ben-Dor et al., 2017). This work indent to provide a new insight to the remote sensing capability to assess SOM and perhaps guide users to better account for SOM in a global view once the hyperspectral sensor will be active from orbit. It will also help farmers in a local (field) scale to assess remotely the fertility of their field in order to improve crop production and quality.
A small, phage-encoded ncRNA maintains lysogeny and blocks virion production in L. monocytogenes 10403S.
L. monocytogenes is a Gram-positive, facultative intracellular pathogen which has been implicated as the causative organism in several outbreaks of foodborne disease. The disease Listeriosis, with a mortality rate of about 24%, is found mainly among pregnant women, their fetuses, and immunocompromised persons, with symptoms of abortion, neonatal death, septicemia, and meningitis. As an intracellular pathogen, L. monocytogenes invades a wide array of mammalian cells. Upon invasion, L. monocytogenes initially resides in a membrane-bound compartment (vacuole or a phagosome) from which it escapes into the host cell cytosol where it replicates efficiently. L. monocytogenes harbors an A118-like prophage within its genome, which is known to reproduce by both lytic and lysogenic cycles. We showed that this prophage (named ϕ10403S) adopted an unusual behavior when L. monocytogenes infects mammalian cells. During macrophage cells infection the prophage, which is inserted within the comK gene, excises its genome leaving an intact comK gene that is necessary to facilitate efficient bacterial phagosomal escape. Prophage excision occurs preferentially within phagosomes, yet, unlike classic prophage induction, progeny virions are not produced and bacterial lysis do not occur. These phenotypes allow the prophage to serve as a molecular switch that controls comK expression and thus promote L. monocytogenes virulence. We named this unique phage behavior “Active lysogeny”. To better understand active lysogeny, we aimed to explore the mechanisms that control or maintain this phage behavior during L. monocytogenes intracellular growth.
Initially, we focused our studies on genes that are located in the lysogenic-lytic switch module. We noticed a predicted ncRNA that is highly transcribed upon lysogenic growth and has no function in the lytic pathway upon lytic inducing conditions. Interestingly, we found that over expression of this transcript has the capacity to inhibit infective virion production by interfering capsid assembly and DNA packaging of the phage. Remarkably, during intracellular growth, a mutated strain of this transcript produces more infective virions than the WT strain in a 4-fold factor. During active lysogeny we do see a block of virion production and expression of critical lytic genes and this ncRNA seems to have an important role in that blockade. However, the specific targets and mechanism of this interference still needs to be revealed.
Population aging in Israel is a process requiring appropriate adaptation of the health care system in order to serve the special needs of the elderly. An important element of health in the older population is food insecurity; its assessment is vital, as it is associated with poor nutritional status and adverse health consequences. Indeed, various studies demonstrate low food intake, functional limitations and increased prevalence of various chronic conditions among food insecure older adults . However, current information regarding food insecurity among the elderly in Israel is scarce, particularly data derived from cohort studies with repeated exposure assessment.
Aims and methods: In this study, we propose to conduct an extensive follow-up interview among ~500 survivors aged ≥75 years of the "MABAT ZAHAV" (Israeli National Health and Nutrition Survey of the Elderly) survey, 11-13 years after their first interview, which included 1800 participants. Information will be obtained at participants' homes in a face-to-face interview. Food security status will be assessed using the USDA short-form questionnaire, similar to the original interview. Information regarding health and nutritional status, socio-demographic and psychosocial status will also be collected, using validated questionnaires. Additionally, follow-up data on time to death was obtained through the Israeli Population Registry.
Data from the interviews will allow us to (1) evaluate whether food insecurity is an independent predictor of mortality during follow-up, and (2) examine what are the factors (socio-demographic, psychosocial and clinical) that have a potential role in the development of food insecurity.
Contribution: Food insecurity is a worldwide public health challenge with devastating consequences among older people. Better understanding of its epidemiology is crucial in order to improve quality of life in the rapidly expanding elderly population. Obtaining data at two points in time, more than a decade apart, in a representative Israeli sample of elderly people, will allow us to assess food security trajectories over the years, their specific risk factors and associated mortality. Understanding the course and etiology of food insecurity in the older population may facilitate preventive interventions.
The first line of plant defense occurs when a plant pattern recognition receptor (PRR) recognizes molecular associated microbial patterns (MAMPs) and as a result, MAMP-triggered immunity (MTI) is triggered, i.e. the activation of various plant defense responses.
One such PRR, is the LRR-RLP (leucine rich repeat-receptor like-protein) LeEix2, which acts as a receptor for the fungal MAMP EIX. EIX was shown to specifically bind to the plasma membrane of both tomato and tobacco responding cultivars and activate defense responses. One such mechanism is the hypersensitivity response (HR) in which planned cell death occurs where EIX was perceived.
In order to identify and isolate genes required for LeEix2 signaling, we will use the CRISPR/Cas9 system for genome editing. The CRISPR/Cas9 system has been successfully applied in several model plants, including tomato. Cas9 is an RNA-guided DNA endonuclease that can use a single-guide RNA (sgRNA) for target recognition and cleavage by a mechanism involving two nuclease active sites that together generate double stranded DNA breaks.
The induction of DSB at target loci can drive site-specific DNA sequence modifications. The modifications include sequence insertion and deletion and other mutations in the host genomes via the error-prone non-homologous end joining (NHEJ) pathway or sequence correction or replacement through the error-free homologous recombination (HR) pathway.
We propose to utilize the CRISPR/Cas9 system as a screening platform in plants. A sgRNA library targeting all tomato genes was designed and will be transformed into an EIX responding tomato cell culture in order to identify genes in the LeEix2-EIX signaling pathway.
My research is focused on understanding the neural correlates of (impaired) decision-making. I aim to disentangle the effects of reward, punishment and non-external reinforced interventions on preference change. My research is aimed to characterize the critical demands for long lasting behavioral change. My research employs behavior, fMRI alongside additional tools such eye tracking and physiological data.
The purpose of the proposed project is to increase the income of Indian farmers that suffer from low productivity, malnutrition and food insecurity by finding innovative solutions for integrating and adapting Israeli technologies to the Indian rural reality.
Israel’s experience and expertise in agriculture holds tremendous potential for Indian agriculture. While some Israeli technologies – such as micro irrigation - are gradually spreading in India, the diffusion of many other technologies with potential to enhance Indian productivity and resource use efficiency remains very slow. Barriers to technology transfer are not only technical/agronomical, but economic. Even though the physical environments in India and Israel are often similar, the economic and social environments are drastically different. Indian farmers operate under very different constraints than those faced by farmers in Israel where Israeli technologies have been proven to work (in terms of finance, scale of operation, institutional setting, knowledge, risk, access to market, etc...).
This project is the first step in a groundbreaking collaboration model between the two countries, meant to fulfill the potential of Israeli technologies in India. Teams of Israeli and Indian students will be embedded in Indo-Israeli Innovation Villages (IIVs) for prolonged periods where they will develop a deep, data based understanding of the needs of local farmers, and then identify, adapt and pilot solutions based on Israeli technologies with appropriate business models.
In addition to the practical value of the program, the data collected in the process - both economic and biophysical - will be used to gain new academic insights into smallholder economics and barriers to technology adoption.
Various species of microalgae have recently emerged as promising host-organisms for biotechnology industries due to their unique properties. These include efficient sunlight conversion into organic compounds, the ability to grow in extreme conditions, and the occurrence of numerous post-translational modification pathways. However, the inability to obtain high levels of nuclear heterologous gene expression in microalgae hinders the development of the entire field.
By combining computational methods and empirical results we showed the importance of proper synthetic gene design. For example, we showed the deleterious effect of unintended splice-sites within the coding sequence and the importance of creating a proper mRNA folding energy profile around the START site. Based upon these initial conclusions, we are currently in the process of expressing human serum albumin, an important pharmaceutical protein, in the C. reinhardtii nucleus.
Simultaneously, we have been studying the chloroplast organelle from a systems biology point of view. Using motif detection and evolutionary deduction we were able to formulate a model for the prediction of chloroplast gene expression based on sequence features of the translation initiation area alone. We are currently in the process of creating a library of C. reinhardtii transformants to validate and improve our model.
Additionally, we are editing the C. reinhardtii chloroplast genome. One of our main goals is to express a functional Fe-Fe-hydrogenase in the chloroplast. Since a major limitation on H2 production in C. reinhardtii is the low enzyme abundance, we plan to use the chloroplast’s natural inclination towards high expression to overcome this barrier.