Session: Foodomics

Session Chair: Prof. Dr. Paola Roncada

Proteomics in food authenticity and food safety

Prof. Dr. Jens Brockmeyer, Uni Stuttgart
The analytical confirmation of the integrity of authentic food is still a major challenge in food sciences. Increasingly complex authenticity claims (organic, regional, vegan) and the introduction of novel foods demand for constant improvement of analytical techniques. In this talk, novel proteomics approaches to ensure the identity and authenticity of complex foods are presented. In addition, the presence of detrimental proteinaceous contaminations such as food allergens or protein fractions able to elicit celiac disease (CD) remain important analytical targets to ensure food safety. Mass spectrometry-based proteomics together with relevant model systems allows insight into structural prerequisites that render allergenicity and the elicitation of CD and helps to develop analytical approaches for the specific and sensitive detection of allergens and gluten fractions.
22-Jun-2022 09:30 (30 Minutes) ICM/Hall 2

What new can we learn about peanut allergens by proteomics?

Prof. Dr. Tanja Cirkovic Velickovic, University of Belgrade

Resistance  to  digestion  by  digestive  proteases  represents  a  critical  property  of  many  food  allergens. However, peanuts, as a lipid-rich food, represent a challenge for downstream analyses of the digestome. This  is  particularly  reflected  in  the  methodological  difficulties  in  analyzing  proteins  and  peptides  in  the presence  of  lipids. Furthermore, different  thermal  treatments  of  peanuts  affect  protein  extraction  and digestion. Roasting of peanuts seems to enhance the extraction of proteins during intestinal digestion toa notable extent. Thermal processing of peanuts impaired the gastrointestinal digestion of the peanut proteins, especially  in  the  case  of  roasted  samples.Post-translational  modifications  (PTMs)  are  covalent  changes occurring on amino acid side chains of proteins, and yet neglected structural and functional aspect of protein architecture. Weconducted a comprehensive bottom-up proteomic study to investigate the impact of peanut roasting  on  readily  soluble  allergens  and  their  PTM  profiles.  Besides  inducing  protein  aggregation  and denaturation, roasting may facilitate change in their PTM pattern and relative profiling.We have shown that Ara h 1 is the most modified major allergen in both samples in terms of modification versatility and extent. The most frequent PTM was oxidation of methionine especially in roasted samples. PTMs uniquely found in roasted samples were, hydroxylation (Trp), formylation (Arg/Lys), and oxidation or hydroxylation (Asn).Proteomic  PTM  profiling  was  confirmed  by  immunoblotting  with  a  series  of  PTM-specific antibodies. Great  variety  of proteoforms of  peanut  allergens is readily  available  for  interaction  with  the immune system.

22-Jun-2022 10:00 (30 Minutes) ICM/Hall 2

Biofilm: From food microbiology to food industry

Prof. Dr. Pierluigi Aldo Di Ciccio, Università degli Studi di Torino
The management of microbial contamination in the food chain is the main goal of the modern food industry. Cross-contamination has been shown to be a risk that causes 25% of food poisoning outbreaks, many of which originate in contaminated surfaces. Microorganisms colonize by adhering surfaces, growing, and forming a self-produced matrix in which multiple microbial species may converge, known as biofilm. Despite the regular application of sanitization plans by food business operators, microbial biofilms are commonly found in food processing environments. Microorganisms organized in biofilm state are embedded in a complex organic matrix composed of polysaccharides, nucleic acids, and proteins. Microbial biofilms can be found wherever moisture and sufficient nutrients are available. In this regard, food processing plants are an ideal environment for biofilm formation by several microorganisms. Biofilms allow microorganisms to better resist harsh environmental conditions. Additionally, conventional cleaning and disinfection protocols normally are not effective in eradicating these biocontaminants. Biofilms are thus a continuous source of persistent spoilage and pathogenic microorganisms leading to repeated contamination of processed food with important economic and safety impact. In the last decades substantial research efforts have been devoted to unraveling mechanisms of biofilm formation, deciphering biofilm architecture, and understanding microbial interactions within those ecosystems. However, biofilms present a high level of complexity and many aspects remain yet to be fully understood. A lot of attention has been also paid to the development of novel strategies for preventing or controlling biofilm formation in industrial settings. This talk aims to provide an overview of the current state of knowledge on the microbial biofilms. Problems associated with mucrobial biofilms in the food industry and recent advances within the “biofilms” field will be presented.
22-Jun-2022 10:30 (30 Minutes) ICM/Hall 2

Proteomic Characterization of Antibiotic Resistance in Listeria and Production of Antimicrobial and Virulence Factors

Dr. Ana González Abril, Instituto de Investigacións Mariñas
Some Listeria species are important human and animal pathogens that can be found in contaminated food and produce a variety of virulence factors involved in their pathogenicity. Listeria strains exhibiting multidrug resistance are known to be progressively increasing and that is why continuous monitoring is needed. Effective therapy against pathogenic Listeria requires identification of the bacterial strain involved, as well as determining its virulence factors, such as antibiotic resistance and sensitivity. The present study describes the use of liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI–MS/MS) to do a global shotgun proteomics characterization for pathogenic Listeria species. This method allowed the identification of a total of 2990 non-redundant peptides, representing 2727 proteins. Furthermore, 395 of the peptides correspond to proteins that play a direct role in Listeria pathogenicity; they were identified as virulence factors, toxins and antitoxins, or associated with either antibiotics (involved in antibiotic-related compounds production or resistance) or resistance to toxic substances. The proteomic repository obtained here can be the base for further research into pathogenic Listeria species and facilitate the development of novel therapeutics for these pathogens [1].
22-Jun-2022 11:00 (30 Minutes) ICM/Hall 2