Publikationen - Molekulare Signalverarbeitung

The increasing global population and climate change pose significant challenges to agriculture, particularly in managing plant diseases caused by phytopathogens. Traditional methods, including chemical pesticides and antibiotics, have become less effective due to pathogen resistance and environmental concerns. Phage therapy emerges as a promising alternative, offering a sustainable and precise approach to controlling plant bacterial diseases without harming beneficial soil microorganisms. This review explores the potential of bacteriophages as biocontrol agents, highlighting their specificity, rapid multiplication, and minimal environmental impact. We discuss the historical context, current applications, and prospects of phage therapy in agriculture, emphasizing its role in enhancing crop yield and quality. Additionally, the paper examines the integration of phage therapy with modern agricultural practices and the development phage cocktails and genetically engineered phages to combat resistant pathogens. The findings suggest that phage therapy could revolutionize phytopathological management, contributing to global food security and sustainable agricultural practices. One-Sentence Summary The burden of plant diseases and phage-based phytopathological treatment.Graphical abstract

Gas chromatography–tandem mass spectrometry with electron ionization (GC–EI–MS/MS) provides rich information on stable-isotope labeling for 13C-metabolic flux analysis (13C-MFA). To pave the way for the routine application of tandem MS data for metabolic flux quantification, we aimed to compile a comprehensive library of GC–EI–MS/MS fragments of tert-butyldimethylsilyl (TBDMS) derivatized proteinogenic amino acids. First, we established an analytical workflow that combines high-resolution gas chromatography-quadrupole time-of-flight mass spectrometry and fully 13C-labeled biomass to identify and structurally elucidate tandem MS amino acid fragments. Application of the high-mass accuracy MS procedure resulted into the identification of 129 validated precursor–product ion pairs of 13 amino acids with 30 fragments being accepted for 13C-MFA. The practical benefit of the novel tandem MS data was demonstrated by a proof–of–concept study, which confirmed the importance of the compiled library for high-resolution 13C-MFA.

Mutualistic symbioses between plant roots and microorganisms can reduce the demand for chemical fertilizers in agriculture. Most crops are able to establish arbuscular mycorrhiza (AM) symbiosis with fungi to take up phosphate more efficiently. A second symbiosis, nitrogen-fixing root nodule symbiosis, supersedes energy-intensive nitrogen fertilization: Legumes such as peas, clover and soybeans take up rhizobia – special bacteria that are capable of converting atmospheric nitrogen into ammonium – into their root cells. Plant root cells perceive rhizobia and AM fungi via very similar signaling molecules (N-acetylglucosamine tetra- or pentamers), even though the resultant developmental processes differ strongly. Interestingly, N-acetylglucosamine containing signals including fungal chitin- and bacterial peptidoglycan-fragments from their cell walls, also play a role in the recognition of pathogenic microorganisms.Despite the intrinsic sustainability potential of the nitrogen-fixing root nodule symbiosis, too much of a good thing, however, has led to global problems: The massive increase in global meat production is largely based on soybean. Large scale soybean monoculture destroyed ecosystems in South America. Large scale animal production results in excessive methane and nitrogen release into the environment, which causes climate change and death zones in marine ecosystems, respectively. This calls for a considerable reduction in meat consumption.

Plant secondary metabolites, also termed specialized plant metabolites, currently comprise more than 200 000 natural products that are all based on a few biosynthetic pathways and key primary metabolites. Some pathways like flavonoid and terpenoid biosynthesis are universally distributed in the plant kingdom, whereas others like alkaloid or cyanogenic glycoside biosynthesis are restricted to a limited set of taxa. Diversification is achieved by an array of mechanisms at the genetic and enzymatic level including gene duplications, substrate promiscuity of enzymes, cell‐specific regulatory systems, together with modularity and combinatorial aspects. Specialized metabolites reflect adaptations to a specific environment. The observed diversity illustrates the heterogeneity and multitude of ecological habitats and niches that plants have colonized so far and constitutes a reservoir of potential new metabolites that may provide adaptive advantage in the face of environmental changes. The code that connects the observed chemical diversity to this ecological diversity is largely unknown. One way to apprehend this diversity is to realize its tremendous plasticity and evolutionary potential. This chapter presents an overview of the most widespread and popular secondary metabolites, which provide a definite advantage to adapt to or to colonize a particular environment, making the boundary between the “primary” and the “secondary” old fashioned and blurry.