This project will investigate the role of the N-end rule pathway of targeted proteolysis in the plant response against pathogens. Through advanced proteomics and transcriptomics approaches we aim to identify protein substrates regulated by a specific branch of the N-end rule pathway and investigate their role in the defense response. We will analyse new N-end rule associated genetic resources in barley that should increase resistance to pathogens. This work will provide evidence for a novel post-translational mechanism within the plant immune response, and resources to develop crops with increased resistance to pathogens.

Beer is a poor and rather hostile environment for most microorganisms comprising poor nutritional availability, ethanol concentration ranging from 4-5%, pH's ranging from pH 3.8 to 4.7, high carbon dioxide concentration (approximately 0.5% w/w) and extremely low oxygen content (<0.1 ppm). These conditions are ideal for strict anaerobes such as Pectinatus spp. And Megasphaera spp. Pectinatus spp play a major role in 20/30% of bacterial incidents, mainly in nonpasteurized beer rather than in pasteurized beer. The most characteristic feature of spoilage caused by Pectinatus spp. is extensive turbidity and an offensive 'rotten egg' smell brought by the combination of various fatty acids, hydrogen sulphide and methyl mercaptan. This spoilage activity can cause serious damages for breweries. Megasphaera has emerged in breweries along with Pectinatus and is responsible for 3-7% of bacterial beer incidents. Beer spoilage caused by this organism results in a similar extreme turbidity as Pectinatus and the production of considerable quantities of butyric acid together with smaller amounts of acetic, isovaleric, valeric and caproic acids as well as acetoin. Like Pectinatus, the production of hydrogen sulphide causes a fecal odor in beer. Titanium dioxide (TiO2) is receiving considerable research interest as a photocatalyst and consequently an antimicrobial coating. Titanium dioxide thin films have been formed on glass, steel and other surfaces by a wide range of techniques, especially by sol/gel and chemical vapour deposition. Commercial products making use of TiO2 photocatalyst include self cleaning glasses such as Pilkington Activ and Saint Gobain Bioclean, self cleaning tiles (TOTO Inc.) and in air purifiers. The ability of silver/titania thin films to act as antimicrobial coatings has received scant attention, although one report on preliminary antimicrobial tests showed that the coating halts E. coli colony formation. The use of silver as a microbicide is well known and a host of commercial products exist for use in wound dressings, ear-pieces, face masks, catheters, plasters and even for deodorisation of socks. A number of commercial antimicrobial surface treatments also exist which rely on the microbicidal activity of the Ag+ ion/these include AgION (AgION Technologies Inc.) and SilvaGard (AcryMed Inc.). In all of these instances the silver is impregnated in the products in its nanoparticulate form or as a silver salt such as silver nitrate. Recent presentations (European Brewing Convention, 2007 and American Society of Brewing Chemists, 2007, unpublished data) from Erna Storngaards (VTT, Finland) suggest that Silver may represent an effective antimicrobial agent against key brewery spoilage bacteria. It is suggested that silver and silver/TiO2 composite coatings may (1) prevent biofilm formation in brewery vessels and pipes, (2) limit microbial loading during final pack filling and (3) increase microbial stability in final pack. Specific Objectives of the Proposed Study 1) Materials scientists will develop nanoparticles or thin surface technologies to produce surfaces for assessment of antimicrobial activity (Prof Steve Howdle). 2) The surfaces will be assessed for durability, tolerance to brewery based cleaning agents and surface coverage using nanotechnology approaches (Prof Clive Roberts). 3) The susceptibility of production and wild yeast, lactic acid bacteria and anaerobic final pack spoilage microorganisms to the surfaces will be assessed (Prof Katherine Smart). 4) Action of the active surface components on cellular function on Pectinatus and Megasphaera spp will be established to identify mode of kill and potential for resistance acquisition to be established (Prof Katherine Smart).

In order to maintain food security for a growing population under climate change, there is a pressing need to develop crops that use less water and that are more tolerant to environmental stresses, particularly drought. Our recent research at the Universities of Nottingham and Sheffield using the laboratory model Arabidopsis thaliana (the plant equivalent of a lab-rat) has identified plants that are extremely tolerant to drought stress. The drought tolerant plants lack the ability to recognise particular proteins inside their cells and send them for destruction by a biochemical process called the N-end rule pathway. From our analysis so far, we already have an important clue as to the identity of the 'drought tolerance protein' that is not destroyed and is therefore stabilised in our drought-tolerant plants. We know that this protein has the amino acid residues methionine and cysteine at one end. In this project we shall identify which specific protein(s) are stabilised in our plants providing us with important information on how we could, in the future, make plants more drought-tolerant. We will also find out if the same N-end rule drought tolerance system works in an important UK crop, barley. Many parts of the UK have experienced unusual and extended periods of drought over the past year which has included the driest 12 months since records began in 1910. This has led to a high level of crop failure with 2011 grain yields being particularly affected. Farmers have reported failure of 10% to 50% of their barley crop, and the surviving barley grain has often been of poor quality, only suitable for low value animal feed rather than for beer-making. As this is a problem for both farmers and brewers, SABMiller a major UK brewing company have agreed to fund part of our research project. SABMiller are committed to reducing the amount of water that they use, and believe that a better understanding of how barley responds to drought may help them to achieve this aim. Our research falls directly within the remit of Global Food Security and Living with Environment Change cross-council priorities identified by the UK Research Councils. The project will help to address the BBSRC strategic research priority Food Security (Crop Science) and our collaboration with SABMiller addresses the Building Partnerships (Collaborative Research with Users) agenda.

Selection for improved characteristics of crops and animals over the millennia of modern human history has benefited from the ability to breed. Artificial selection for such improvement through selective breeding feeds the world as well as gives us the wide variety of dog breeds, faster race horses, etc. Without the ability to breed there is limited variation on which to base improvements. Many plants, including various crops of great importance such as wheat, originated from the hybridization of two or more closely related species. These initially were sterile and dead ends in terms of evolution but overcame their sterility by duplicating their genomes. Variation could still be limited in these as the fertile derivatives may have occurred only once in history resulting in variation being fixed at that point and accumulated over time via mutations. A lot of effort goes into crop improvement by introgressing chromosomes from parental species of the hybrids to bring in new variation. In animals it is more difficult to overcome sterility and so working animals such as mules can only really be improved by breeding in the horse and donkey parents and hoping for improved characteristics in each new mules created by mating the two parents. This is a hit or miss approach and not very efficient. In fermentation uses with yeast there are hybrids that are used, the most famous being the lager yeast Saccharomyces carlsbergensis. There are also some used in the wine industry and others are found in nature. These are sterile hybrids which preclude improvement by breeding. In this project we overcome the sterility barrier by duplicating the genomes of several new and existing hybrids, first to determine the genetics of particular characteristics, like why does lager yeast ferment better at cold temperatures, and then to create new diverse hybrids with improved or even new characteristics. We will generate a large number of new hybrids and explore their characteristics, isolating useful strains for use in brewing and wine making as well as industrial production strains. We will also learn about the biology of hybrids and how their two genomes interact. Finally we will answer the question 'Can mules evolve?'

This project will define the function of key candidate genes in barley germination and malting quality by transferring information from genetic studies in Arabidopsis. Using the multidisciplinary team assembled here, for the first time we will be able to answer specific questions about the comparative biology of germination, the function of key regulatory pathways, and the influence of these components on malting characteristics and brewing functionality. The project will provide new genetic resources for germination studies and present a framework for the successful transfer of information from Arabidopsis to cereals.