Bioactive molecules produced by Heterorhabditis bacteriophora after in vitro stimulation by insect tissue

ELIÁŠ, Sara, Jana ILGOVÁ, Jana HURYCHOVÁ, Paola ALBERT POYÁN, Pavel DOBEŠ, Martin KAŠNÝ and Pavel HYRŠL. Bioactive molecules produced by Heterorhabditis bacteriophora after in vitro stimulation by insect tissue. In 18th meeting IOBC/WPRS Working Group Microbial and Nematode Control of Invertebrate Pests. 2022.

Basic information

• Original name: Bioactive molecules produced by Heterorhabditis bacteriophora after in vitro stimulation by insect tissue
• Name in Czech: Bioactive molecules produced by Heterorhabditis bacteriophora after in vitro stimulation by insect tissue
• Authors: ELIÁŠ, Sara (276 Germany, belonging to the institution), Jana ILGOVÁ (703 Slovakia, belonging to the institution), Jana HURYCHOVÁ (203 Czech Republic, belonging to the institution), Paola ALBERT POYÁN (724 Spain, belonging to the institution), Pavel DOBEŠ (203 Czech Republic, belonging to the institution), Martin KAŠNÝ (203 Czech Republic) and Pavel HYRŠL (203 Czech Republic, guarantor, belonging to the institution).
• Edition: 18th meeting IOBC/WPRS Working Group Microbial and Nematode Control of Invertebrate Pests, 2022.

Other information

• Original language: English
• Type of outcome: Conference abstract
• Field of Study: 10616 Entomology
• Country of publisher: Czech Republic
• Confidentiality degree: is not subject to a state or trade secret
• WWW: URL
• RIV identification code: RIV/00216224:14310/22:00129440
• Organization unit: Faculty of Science
• Keywords (in Czech): Heterorhabditis bacteriophora; secreted/excreted products; entomopathogenic nematodes
• Keywords in English: Heterorhabditis bacteriophora; secreted/excreted products; entomopathogenic nematodes
• Tags: International impact

Abstract

Entomopathogenic nematodes produce bioactive molecules referred to as excreted/secreted products (ESPs). The ESPs comprise a mixture of proteins, lipids, glycans, and nucleic acids that can interfere with the host immune system in order to increase the chance of entomopathogenic nematodes to reproduce. Infective juveniles (IJs), the only free-living stage of nematodes, release ESPs typically in the early phase of infection when contacted with host tissues. The spectrum of ESPs has not yet been fully described, however, its quantitative and qualitative changes during the process of nematode infection were observed. Of particular importance are the immune-modulating proteins, such as proteolytic enzymes and their inhibitors, which have not yet been largely investigated. There are several approaches how to in vitro stimulate IJs to produce ESPs. We investigated the possible effect of various induction materials and time-related parameters on the yield of ESPs. We induced IJs of Heterorhabditis bacteriophora using four differently prepared Galleria mellonella homogenates and tested two time points of IJs induction and subsequent ESPs production. Based on our findings, the time of the IJs induction does not significantly affect the protein concentration of collected ESPs. However, we observed that the induction material affects the ESPs protein quantity. The collected ESPs were further characterised by mass spectrometry to identify proteins present in ESPs and suggest their function. According to GO annotation of mass spectrometric data, lipid-binding proteins, peptidase inhibitors, peptidases, and proteins with chitinase activity are among the most abundant groups of ESP components. As one of the major fractions determined by mass spectrometry were peptidases, we further focussed on their proteolytic activity and observed the presence of serine proteases. Our preliminary mass spectrometry data allow us to continue with identification and functional characterization of candidate bioactive molecules.

Abstract (in Czech)

Entomopathogenic nematodes produce bioactive molecules referred to as excreted/secreted products (ESPs). The ESPs comprise a mixture of proteins, lipids, glycans, and nucleic acids that can interfere with the host immune system in order to increase the chance of entomopathogenic nematodes to reproduce. Infective juveniles (IJs), the only free-living stage of nematodes, release ESPs typically in the early phase of infection when contacted with host tissues. The spectrum of ESPs has not yet been fully described, however, its quantitative and qualitative changes during the process of nematode infection were observed. Of particular importance are the immune-modulating proteins, such as proteolytic enzymes and their inhibitors, which have not yet been largely investigated. There are several approaches how to in vitro stimulate IJs to produce ESPs. We investigated the possible effect of various induction materials and time-related parameters on the yield of ESPs. We induced IJs of Heterorhabditis bacteriophora using four differently prepared Galleria mellonella homogenates and tested two time points of IJs induction and subsequent ESPs production. Based on our findings, the time of the IJs induction does not significantly affect the protein concentration of collected ESPs. However, we observed that the induction material affects the ESPs protein quantity. The collected ESPs were further characterised by mass spectrometry to identify proteins present in ESPs and suggest their function. According to GO annotation of mass spectrometric data, lipid-binding proteins, peptidase inhibitors, peptidases, and proteins with chitinase activity are among the most abundant groups of ESP components. As one of the major fractions determined by mass spectrometry were peptidases, we further focussed on their proteolytic activity and observed the presence of serine proteases. Our preliminary mass spectrometry data allow us to continue with identification and functional characterization of candidate bioactive molecules.

Links

• QK1910286, research and development project: Name: Efektivní postupy a strategie pro zvládání včelích chorob a udržitelný chov včelstev

Investor: Ministry of Agriculture of the CR