Protein Breakdown Products Research Articles

ВЕТЕРИНАРНО-САНИТАРНОЕ ОПРЕДЕЛЕНИЕ СТЕПЕНИ СВЕЖЕСТИ МЯСА

The purpose of the study is to conduct a veterinary and sanitary assessment of the freshness of pork and beef and to give a comparative assessment of the change in the degree of freshness of pork and beef depending on the shelf life. The study was conducted in the laboratory of veterinary and sanitary examination of the KSKU “Yenisei Department of Veterinary Medicine” in Lesosibirsk. The research material was chilled meat on the bones of pork and beef. The studies were carried out over 16 days. An organoleptic examination of the meat showed that the pork lost its freshness on the 8th day and became of poor quality on the 12th day. The freshness of the beef went away on the 11–12th day, closer to the 15–16th day it became stale. The results of physical and chemical studies of pork and beef to determine the reaction of the environment (pH) showed that the pork retained its freshness for 6 days (pH 5.6–6.0, corresponds to GOST 51478-99). On days 7–11, the reaction of the medium showed a pH of 6.2–6.5, which indicates questionable freshness. On the 12th day, the pH is 6.5, which indicates that the meat is stale. The beef was fresh for 8 days (pH 6.2), questionable freshness remained for 14 days (pH 6.4), on the 15th day it became stale (pH 6.5.) According to the results of a study of the reaction to primary protein breakdown products with copper sulfate in the broth, pork was fresh for 3 days, beef for 5 days, a negative reaction indicates the appearance of questionable freshness of the meat, this corresponds to GOST 23392-2016. Pork went from a state of questionable freshness to stale on the 8th day, and beef on the 11th day. Based on the results of microscopy of fingerprint smears, questionable freshness appeared in pork on the 4th–5th day, in beef on the 10th day, as evidenced by an increase in the number of microbes on the surface of the meat to 20–30 in the field of view, appearance in the microscope decomposed meat tissues. Pork became stale on the 11th–12th day, beef on the 12th day, while in the field of view of the microscope more than 30 microbes were found on the surface of the meat, intense staining of fingerprint smears and a lot of decomposed tissues. Compared to pork, beef can be stored longer by 2–3 days and retain its freshness. Since pork meat is fatty, it spoils faster and is more favorable for the development of various defects.

Toxic Substances and Their Sources in Feed for Fur-Bearing Animals

The use of a wide variety of animal and plant feeds in fur farming, a significant number of suppliers, as well as the complexity of transportation and storage of feed raw materials increase the risks of feed toxicoinfections and toxicoses. The proposed review article describes in detail the main toxic substances and their sources in fur-bearing animal feed, including biological and chemical toxins, namely bacterial and fungal metabolites, protein breakdown products and fat oxidation, fish biotoxins, heavy metals, persistent organochlorine compounds, pestcides, etc.

Porphyrin-based sensor films for monitoring food spoilage

To increase food safety and to minimize food waste, it is interesting for the food industry and consumers to be able to determine food spoilage continuously and non-destructively. When food of animal origin is degraded, amines are released as protein breakdown products, which could be used to monitor the freshness of meat and fish. In this work, we introduce a porphyrin-based sensor foil aimed at the detection of biogenic amines. The sensor-porphyrin is formulated on mesoporous silica. Reactivity towards moderate humidity was eliminated by dispersion of the functionalized silica in polyethylene (PE), followed by thermal extrusion resulting in PE foils. After exposure to amines, the sensor foil changes its color irreversibly from green to red. The color change is accompanied by a pronounced shift of the fluorescence spectrum, which was used as a sensitive method to detect the degradation of fish products in model experiments. Titanium dioxide particles in the foil increased the detected fluorescence emission. Experiments with fish filets showed the applicability of the sensor foils in a real-life application by indicating the degree of spoilage after several days, while the microbial growth was depicted by total viable count. We anticipate that our sensor can be an integral part of smart food packages, helping to track the freshness of food during transport or storage.

Wild soybean salt tolerance metabolic model: Assessment of storage protein mobilization in cotyledons and C/N balance in the hypocotyl/root axis.

Salt stress has become one of the main factors limiting crop yield in recent years. The post-germinative growth is most sensitive to salt stress in soybean. In this study, cultivated and wild soybeans were used for an integrated metabonomics and transcriptomics analysis to determine whether wild soybean can resist salt stress by maintaining the mobilization of stored substances in cotyledons and the balance of carbon and nitrogen in the hypocotyl/root axis (HRA). Compared with wild soybean, the growth of cultivated soybean was significantly inhibited during the post-germinative growth period under salt stress. Integrating analysis found that the breakdown products of proteins, such as glutamate, glutamic acid, aspartic acid, and asparagine, increased significantly in wild soybean cotyledons. Asparagine synthase and fumarate hydratase genes and genes encoding HSP20 family proteins were specifically upregulated. In wild soybean HRA, levels of glutamic acid, aspartic acid, asparagine, citric acid, and succinic acid increased significantly, and the glutamate decarboxylase gene and the gene encoding carbonic anhydrase in nitrogen metabolism were significantly upregulated. The metabolic model indicated that wild soybean enhanced the decomposition of stored proteins and the transport of amino acids to the HRA in cotyledons and the GABA shunt to maintain carbon and nitrogen balance in the HRA to resist salt stress. This study provided a theoretical basis for cultivating salt-tolerant soybean varieties and opened opportunities for the development of sustainable agricultural practices.

Ендотоксикоз і запалення як предиктори поглиблення функціональної недостатності підшлункової залози при хронічному панкреатиті у поєднанні із цукровим діабетом 2 типу

According to scientists, a significant role in the progression of chronic pancreatitis (CP) and diabetes mellitus (DM), as well as in the occurrence of complications of these diseases, is played by inflammation and endogenous intoxication by the products of protein breakdown as a result of the inflammatory process, fibrosis, and degradation of connective tissue in the patient’s body, in particular, and in the pancreas. The aim is to analyze the state of parameters of inflammation, endotoxicosis, and their influence on the functional capacity of the pancreas in the comorbid course of chronic pancreatitis and type 2 diabetes mellitus (DM2). Materials and methods. 112 patients with CP in the phase of mild therapeutic exacerbation in combination with DM2 in the stage of subcompensation were examined. The results. Moderate and moderate inverse correlations were established between CRP and fecal α-elastase in patients with CP and comorbidity of CP and DM2 (respectively r=-0.423 and r=-0.565, p<0,05). An increase in the strength of reliable direct moderate correlations between the levels of HbA1c and CRP in patients with CP in combination with DM2 compared to those with isolated CP (respectively r=0.313 and r=0.410, p<0,05) was proved. Conclusions: We proved a reliable influence of the index of endogenous intoxication on the level of pancreatic functional insufficiency according to the content of fecal α-elastase, which was more significant in the combined course of CP and DM2 compared to that in isolated CP. An increase in the strength of reliable direct, moderate, and moderate correlations between HbA1c levels and the index of endogenous intoxication in patients with isolated CP and CP in combination with DM2 has been proven.

Calpain-mediated proteolysis as driver and modulator of polyglutamine toxicity.

Among posttranslational modifications, directed proteolytic processes have the strongest impact on protein integrity. They are executed by a variety of cellular machineries and lead to a wide range of molecular consequences. Compared to other forms of proteolytic enzymes, the class of calcium-activated calpains is considered as modulator proteases due to their limited proteolytic activity, which changes the structure and function of their target substrates. In the context of neurodegeneration and - in particular - polyglutamine disorders, proteolytic events have been linked to modulatory effects on the molecular pathogenesis by generating harmful breakdown products of disease proteins. These findings led to the formulation of the toxic fragment hypothesis, and calpains appeared to be one of the key players and auspicious therapeutic targets in Huntington disease and Machado Joseph disease. This review provides a current survey of the role of calpains in proteolytic processes found in polyglutamine disorders. Together with insights into general concepts behind toxic fragments and findings in polyglutamine disorders, this work aims to inspire researchers to broaden and deepen the knowledge in this field, which will help to evaluate calpain-mediated proteolysis as a unifying and therapeutically targetable posttranslational mechanism in neurodegeneration.

Regulation of Nir gene in Lactobacillus plantarum WU14 mediated by GlnR.

Nitrogen (N) is an essential element in the biosynthesis of key cellular components, such as proteins and nucleic acids, in all living organisms. Nitrite, as a form of nitrogen utilization, is the main nutrient for microbial growth. However, nitrite is a potential carcinogen that combines with secondary amines, which are breakdown products of proteins, to produce N-nitroso compounds that are strongly carcinogenic. Nitrite reductase (Nir) produced by microorganisms can reduce nitrite. Binding of GlnR to the promoter of nitrogen metabolism gene can regulate the expression of Nir operon. In this study, nitrite-resistant Lactobacillus plantarum WU14 was isolated from Pickles and its protease Nir was analyzed. GlnR-mediated regulation of L. plantarum WU14 Nir gene was investigated in this study. New GlnR and Nir genes were obtained from L. plantarum WU14. The regulation effect of GlnR on Nir gene was examined by gel block test, yeast two-hybrid system, bacterial single hybrid system and qRT-RCR. Detailed analysis showed that GlnR ound to the Nir promoter region and interacted with Nir at low nitrite concentrations, positively regulating the expression of NIR. However, the transcription levels of GlnR and Nir decreased gradually with increasing nitrite concentration. The results of this study improve our understanding of the function of the Nir operon regulatory system and serve as the ground for further study of the signal transduction pathway in lactic acid bacteria.

Characterization of Calpain and Caspase-6-Generated Glial Fibrillary Acidic Protein Breakdown Products Following Traumatic Brain Injury and Astroglial Cell Injury.

Glial fibrillary acidic protein (GFAP) is the major intermediate filament III protein of astroglia cells which is upregulated in traumatic brain injury (TBI). Here we reported that GFAP is truncated at both the C- and N-terminals by cytosolic protease calpain to GFAP breakdown products (GBDP) of 46-40K then 38K following pro-necrotic (A23187) and pro-apoptotic (staurosporine) challenges to primary cultured astroglia or neuron-glia mixed cells. In addition, with another pro-apoptotic challenge (EDTA) where caspases are activated but not calpain, GFAP was fragmented internally, generating a C-terminal GBDP of 20 kDa. Following controlled cortical impact in mice, GBDP of 46-40K and 38K were formed from day 3 to 28 post-injury. Purified GFAP protein treated with calpain-1 and -2 generates (i) major N-terminal cleavage sites at A-56*A-61 and (ii) major C-terminal cleavage sites at T-383*Q-388, producing a limit fragment of 38K. Caspase-6 treated GFAP was cleaved at D-78/R-79 and D-225/A-226, where GFAP was relatively resistant to caspase-3. We also derived a GBDP-38K N-terminal-specific antibody which only labels injured astroglia cell body in both cultured astroglia and mouse cortex and hippocampus after TBI. As a clinical translation, we observed that CSF samples collected from severe human TBI have elevated levels of GBDP-38K as well as two C-terminally released GFAP peptides (DGEVIKES and DGEVIKE). Thus, in addition to intact GFAP, both the GBDP-38K as well as unique GFAP released C-terminal proteolytic peptides species might have the potential in tracking brain injury progression.

Generation and Release of Neurogranin, Vimentin, and MBP Proteolytic Peptides, Following Traumatic Brain Injury.

Traumatic brain injury (TBI) is a major neurological disorder without FDA-approved therapies. In this study, we have examined the concept that TBI might trigger global brain proteolysis in the acute post-injury phase. Thus, we conducted a systemic proteolytic peptidomics analysis using acute cerebrospinal fluid (CSF) samples from TBI patients and normal control samples. We employed ultrafiltration-based low molecular weight (LMW; < 10kDa) peptide enrichment, coupled with nano-reversed-phase liquid chromatography/tandem mass spectrometry analysis, followed with orthogonal quantitative immunoblotting-based protein degradation analysis. We indeed identified novel patterns of injury-dependent proteolytic peptides derived from neuronal components (pre- and post-synaptic terminal, dendrites, axons), extracellular matrix, oligodendrocytes, microglial cells, and astrocytes. Among these, post-synaptic protein neurogranin was identified for the first time converted to neurogranin peptides including neurogranin peptide (aa 16-64) that is phosphorylated at Ser-36/48 (P-NG-fragment) in acute human TBI CSF samples vs. normal control with a receiver operating characteristic area under the curve of 0.957. We also identified detailed processing of astroglia protein (vimentin) and oligodendrocyte protein (MBP and Golli-MBP) to protein breakdown products (BDPs) and/or LMW proteolytic peptides after TBI. In addition, using MS/MS selected reaction monitoring method, two C-terminally released MBP peptides TQDENPVVHFF and TQDENPVVHF were found to be elevated in acute and subacute TBI CSF samples as compared to their normal control counterparts. These findings imply that future therapeutic strategies might be placed on the suppression of brain proteolysis as a target. The endogenous proteolytic peptides discovered in human TBI biofluid could represent useful diagnostic and monitoring tools for TBI.

Changes in Pork Freshness Indicators When Stored at Positive Temperatures

The article examines the processes occurring during the ripening of pork meat during storage at a temperature of 0–4 °C. Particular attention is paid to a group of chemical indicators of freshness of raw meat: acidity (pH), mass fraction of sodium chloride, and the presence of protein breakdown products. The author concludes that instrumental methods, along with methods of organoleptic control of raw meat, make it possible to assess the properties of meat more accurately. Based on the study of samples, it was established that measuring the pH (acidity) of meat 24 hours after slaughter and in the subsequent period allows characterizing in detail the autolysis process and detect signs of NOR, PSE or DED. Considering changes in pH values, it is possible to determine the direction of use of raw meat. It was revealed that the mass fraction of sodium chloride does not change during maturation and storage under the conditions under study. In all samples, the presence of protein degradation products was not detected.

Adsorption of protein breakdown products and toxins by erythrocytes

It has been established that amino acids enter the bloodstream through the intestinal walls in an unchanged form, and both these substances and parenterally administered protein breakdown products cannot be detected either in serum or in whole blood soon after their introduction. BI Zbarsky (Zhurn. Exp. Biol., 1925, No. 1) explains this fact by the adsorption of protein breakdown products by blood erythrocytes, from which these products can be easily separated by simple boiling, and which transfer these products to the cells of the body.

Explosive-driven double-blast exposure: molecular, histopathological, and behavioral consequences

Traumatic brain injury generated by blast may induce long-term neurological and psychiatric sequelae. We aimed to identify molecular, histopathological, and behavioral changes in rats 2 weeks after explosive-driven double-blast exposure. Rats received two 30-psi (~ 207-kPa) blasts 24 h apart or were handled identically without blast. All rats were behaviorally assessed over 2 weeks. At Day 15, rats were euthanized, and brains removed. Brains were dissected into frontal cortex, hippocampus, cerebellum, and brainstem. Western blotting was performed to measure levels of total-Tau, phosphorylated-Tau (pTau), amyloid precursor protein (APP), GFAP, Iba1, αII-spectrin, and spectrin breakdown products (SBDP). Kinases and phosphatases, correlated with tau phosphorylation were also measured. Immunohistochemistry for pTau, APP, GFAP, and Iba1 was performed. pTau protein level was greater in the hippocampus, cerebellum, and brainstem and APP protein level was greater in cerebellum of blast vs control rats (p < 0.05). GFAP, Iba1, αII-spectrin, and SBDP remained unchanged. No immunohistochemical or neurobehavioral changes were observed. The dissociation between increased pTau and APP in different regions in the absence of neurobehavioral changes 2 weeks after double blast exposure is a relevant finding, consistent with human data showing that battlefield blasts might be associated with molecular changes before signs of neurological and psychiatric disorders manifest.

Prospects for Salted Pacific Sardine (Ivasi) as a Raw Material for Emulsion Products

Expanding the range of functional food products is one of the important tasks of the Russian state policy to improve the population health. Water bioresources due to their high biological value consists of the potential for creating such products. The article presents the technological characteristics of the Pacific salted sardine (iwasi) as a promising highfat raw material rich in valuable natural lipids for multi-component emulsion products. The Pacific sardine (ivasi) extracted in the far East is a mass object of marine fishing. However, the food production from the sardines is currently limited by frozen and salted fish. In order to expand the food product range from the Pacific sardine (ivasi), the paper concerns the technological parameters of the salted fish production process and justification of its use as a basis for emulsion systems. The authors present technological scheme for obtaining salted Pacific sardine (iwashi) from frozen fish. The dynamic analysis of proteolysis indicators during the storage period of salted sardines indicates an active accumulation of protein breakdown products during the protein component destruction. Organoleptic assessment of salted fish performed in the third and fourth months of storage showed that, in the absence of discrediting organoleptic signs in the samples under study, a man recorded the destruction of the abdominal area in the fourth month of storage. The rheological studies results of finely ground muscle tissue of salted sardines, in comparison with frozen fish, demonstrate an increase in these indicators in the proteolysis process. Biochemical, rheological and organoleptic characteristics of salted Pacific sardine (iwasi) in the fourth month of storage indicate its high raw material potential for use in the technology of emulsion products.

Veterinary-sanitary inspection of cattle meat affected with benign tumor

The rate of benign tumor detection in slaughtered cattle was studied. Tumor pathology was detected on average in 0.04% of the studied livestock. Manifestations of various new growths in this animal species have specific features. Tumors are detected 2-3 times more often in cows and bulls than in young animals. The veterinary and sanitary characteristics of cattle meat affected with benign tumors were compared with those of animal meat without tumors. Affected meat had deviations in physical properties, chemical composition of meat affected with tumors, content of primary protein breakdown products, volatile fatty acids (+0.05 mg/KOH) and amino-ammonium nitrogen (+0.54 mg/%) compared with meat of healthy cattle. It was revealed that the samples of meat affected with tumors were highly contaminated with microorganisms (0.28…0.80×102), including coliforms and St. aureus . Pathogenic bacteria of the genera Salmonella , L. monocytogenes , Cl. perfringens etc. were not detected in the test samples. In meat affected with tumors, relative bioavailability decreased by 4.99…13.87% and safety - by 5.89…13.89% as compared to meat of healthy cattle. Based on the data obtained, proposals were developed on the most rational and safe use of meat from animals affected by benign tumors for food and feed.

Plant-microbe competition: does injection of isotopes of C and N into the rhizosphere effectively characterise plant use of soil N?

Despite considerable attention over the last 25yr, the importance of early protein breakdown products to plant nitrogen (N) nutrition remains uncertain. We used rhizosphere injection of 15 N-, 13 C- and 14 C-labelled inorganic N and amino acid (l-alanine), with chase periods from 1min to 24h, to investigate the duration of competition for amino acid between roots (Triticum aestivum) and soil microorganisms. We further investigated how microbial modification of l-alanine influenced plant carbon (C) and N recovery. From recovery of C isotopes, intact alanine uptake was 0.2-1.3% of added. Soil microbes appeared to remove alanine from soil solution within 1min and release enough NH4+ to account for all plant 15 N recovery (over 24h) within 5min. Microbially generated inorganic or keto acid C accounted for <25% of the lowest estimate of intact alanine uptake. Co-location of C and N labels appears a reasonable measure of intact uptake. Potential interference from microbially modified C is probably modest, but may increase with chase period. Similarly, competition for l-alanine is complete within a few minutes in soil, whereas NO3- added at the same rate is available for >24h, indicating that long chase periods bias outcomes and fail to accurately simulate soil processes.

Cerebrospinal Fluid Biomarkers Are Associated With Glial Fibrillary Acidic Protein and αII-spectrin Breakdown Products in Brain Tissues Following Penetrating Ballistic-Like Brain Injury in Rats.

Treatments to improve outcomes following severe traumatic brain injury (TBI) are limited but may benefit from understanding subacute-chronic brain protein profiles and identifying biomarkers suitable for use in this time. Acute alterations in the well-known TBI biomarkers glial fibrillary acidic protein (GFAP), αII-spectrin, and their breakdown products (BDPs) have been well established, but little is known about the subacute-chronic post-injury profiles of these biomarkers. Thus, the current study was designed to determine the extended profile of these TBI-specific biomarkers both in brain tissue and cerebral spinal fluid (CSF). Protein abundance was evaluated in brain tissue samples taken from regions of interest and in CSF at 24 h, 3 days, 7 days, 1 month, and 3 months following severe TBI in rats. Results showed increased full length GFAP (GFAP-FL) and GFAP-BDPs starting at 24 h that remained significantly elevated in most brain regions out to 3 months post-injury. However, in CSF, neither GFAP-FL nor GFAP-BDPs were elevated as a consequence of injury. Regional-specific reduction in αII-spectrin was evident in brain tissue samples from 24 h through 3 months. In contrast, SBDP-145/150 was robustly elevated in most brain regions and in CSF from 24 h through 7 days. Correlation analyses revealed numerous significant relationships between proteins in CSF and brain tissue or neurological deficits. This work indicates that TBI results in chronic changes in brain protein levels of well-known TBI biomarkers GFAP, αII-spectrin, and their BDPs and that SBDP-145/150 may have utility as an acute-chronic biomarker.

Endogenous protein and enzyme fragments induce immunoglobulin E‐independent activation of mast cells via a G protein‐coupled receptor,MRGPRX2

Mast cells play a central role in inflammatory and allergic reactions by releasing inflammatory mediators through 2 main pathways, immunoglobulin E-dependent and E-independent activation. In the latter pathway, mast cells are activated by a diverse range of basic molecules (collectively known as basic secretagogues) through Mas-related G protein-coupled receptors (MRGPRs). In addition to the known basic secretagogues, here, we discovered several endogenous protein and enzyme fragments (such as chaperonin-10 fragment) that act as bioactive peptides and induce immunoglobulin E-independent mast cell activation via MRGPRX2 (previously known as MrgX2), leading to the degranulation of mast cells. We discuss the possibility that MRGPRX2 responds various as-yet-unidentified endogenous ligands that have specific characteristics, and propose that MRGPRX2 plays an important role in regulating inflammatory responses to endogenous harmful stimuli, such as protein breakdown products released from damaged or dying cells.

Organoleptic Changes of the Fermented Autolysate of Fish

In Benin, fermented autolysates of fish are neglected. This neglect is largely due to their strong smell and lack of knowledge of their nutritional value. Knowledge of certain physicochemical parameters during the fermentation process may allow to know the chemical changes that occurred during the transformation of the fish autolysate. Thus, a kinetic fermentation study of three different autolysates based on electrical conductivity (EC), total dissolved solids (TDS) and pH is done to understand the origin of the consumption rejection of fermented autolysates in Benin. The obtained results show that the electrical conductivities vary between 3077μS and 3206μS for tuna, between 3049μS and 3216μS for the bass, between 2700μS and 2975μS for catfish. Tuna, bass and catfish have arerage TDS of 2040mg / L, 2029mg / L and 1847mg / L, respectively. As for pH, they vary from 7.70 to 8.71 for tuna, from 7.96 to 8.80 for the bass and from 7.92 to 8.29 for catfish. The analysis of the kinetics of electrical conductivities and of TDS reveals that the latter are identical and present three different phases, namely a regression which corresponds to a grouping of the particles in the medium, an increase which shows the fluctuation of the particles and a stabilization which indicates the end of the fermentation. Analysis of pH kinetics shows that the fermentation medium is basic. This proves that the particles in suspension of the fermentation medium are dimethylamine, trimethylamine, ammonia, etc. The fermented autolysates of fish are rich in amino acids and fatty acids (protein and lipid breakdown products), and their strong smell is due to volatile bases resulting from the reaction of amines.

Mechanosensitive ion channel Piezo1 is expressed in antral G cells of murine stomach

G cells in the antrum region of the murine stomach produce gastrin, the central hormone for controlling gastric activities. Secretion of gastrin is induced mainly by protein breakdown products but also by distensions of the stomach wall. Although G cells respond to protein fragments via distinct chemosensory receptor types, the mechanism underlying G cell activation upon distention is entirely ambiguous. Mechanosensitive ion channels are considered as potential candidates for such a task. Therefore, we explore the possibility of whether Piezo1, a polymodal sensor for diverse mechanical forces, is expressed in antral G cells. The experimental analyses revealed that the vast majority of G cells indeed expressed Piezo1. Within flask-like G cells at the base of the antral invaginations, the Piezo1 protein was primarily located at the basolateral portion, which is thought to be the release site for the exocytic secretion of gastrin. In the spindle-like G cells, which are oriented parallel to the invaginations, Piezo1 protein was restricted to the cell body where the hormone was also located, whereas the long processes appeared to be devoid of Piezo1 protein. Our results suggest that mechanosensitive channels such as Piezo1, located in close proximity to hormone-release sites, enable G cells to respond directly to antrum distensions with gastrin secretion.

Aerial Warfare: A Volatile Dialogue between the Plant Pathogen Verticillium longisporum and Its Antagonist Paenibacillus polymyxa.

Verticillium wilt caused by Verticillium spp. results in severe yield losses in a broad range of crops. Verticillium outbreaks are challenging to control, and exacerbated by increases in soil temperatures and drought associated with global warming. Employing natural antagonists as biocontrol agents offers a promising approach to addressing this challenge. Paenibacillus polymyxa Sb3-1 was proven to reduce the growth of Verticillium longisporum during in vitro experiments and was shown to promote the growth of oilseed rape seedlings infested with V. longisporum. Our novel approach combined in vitro and in planta methods with the study of the mode of interaction between Sb3-1 and V. longisporum EVL43 via their volatile organic compounds (VOCs). Volatile and soluble substances, produced by both microorganisms as a reaction to one another's VOCs, were detected by using both gas and liquid chromatography-mass spectrometry. P. polymyxa Sb3-1 continually produced antimicrobial and plant growth promoting VOCs, such as 2-nonanone and 3-hydroxy-2-butanone. Several other antimicrobial volatile substances, such as isoamyl acetate and durenol, were downregulated. The general metabolic activity of Sb3-1, including protein and DNA biotransformations, was upregulated upon contact with EVL43 VOCs. V. longisporum increased its production of antimicrobial substances, such as 1-butanol, and downregulated its metabolic activities upon exposure to Sb3-1 VOCs. Additionally, several stress response substances such as arabitol and protein breakdown products (e.g., L-Isoleucyl-L-glutamic acid), were increased in the co-incubated samples. The results obtained depict an ongoing dialog between these microorganisms resulting in growth inhibition, the slowing down of metabolism, and the cell death of V. longisporum due to contact with the P. polymyxa Sb3-1 VOCs. Moreover, the results indicate that VOCs make a substantial contribution to the interaction between pathogens and their natural antagonists and have the potential to control pathogens in a novel, environmentally friendly manner.