Digging Deeper Into the Pyriproxyfen-Response of the Amphipod Gammarus fossarum With a Next-Generation Ultra-High-Field Orbitrap Analyser: New Perspectives for Environmental Toxicoproteomics

Abstract

Taxon-specific proteins from sentinel species have been shown to be among the most relevant proteins to monitor the biological effects of anthropogenic contaminations. Shotgun proteomics allows high-throughput analysis of animal proteomes, but comprehensive coverage remains difficult to achieve due to the wide dynamic range. Here, the advantages of a new generation of mass analyser for environmental toxicoproteomics are documented through the identification of candidate biomarkers in a sentinel animal species for which the genome is as yet unsequenced. A label-free comparative proteomic study was performed on testis from the freshwater amphipod Gammarus fossarum challenged with 0.5 µg or 50 µg/L pyriproxyfen, a juvenile hormone analog used as an insecticide. A total of 4,031 proteins could be monitored with a Q Exactive HF mass spectrometer incorporating an ultra-high-field Orbitrap analyser. Five times more MS/MS spectra and 4-fold more peptides and proteins were identified with this instrument compared to a LTQ Orbitrap XL spectrometer. Comparison of protein abundance between control and organisms exposed to 0.5 µg or 50 µg/L pyriproxyfen indicated that 32 and 21 proteins, respectively, were significantly modulated between test and control conditions. Functional annotation of these novel candidate biomarkers and their specificities are discussed in light of their potential applications in freshwater quality monitoring. The potential contribution of next-generation mass spectrometers to environmental toxicoproteomics is also touched on.

Evaluation of DNA Damage, Biomarkers of Oxidative Stress, and Status of Antioxidant Enzymes in Freshwater Fish (Labeo rohita) Exposed to Pyriproxyfen

“…Moreover, it can be speculated that DNA damage in different tissues of Labeo rohita might also be related to genetic abnormalities induced by PPF leading to the activation of abnormal and physiologically nonfunctional proteins responsible for mitochondrion dysfunctioning and breakage of nuclear proteins [80,81]. Furthermore, DNA damage in multiple organs of the Labeo rohita might be linked to genetic abnormalities generated by PPF, which could lead to the activation of aberrant and physiologically nonfunctional proteins that cause mitochondrion dysfunction and nuclear protein breakdown [1,82,83].…”

Subcellular Distribution of Dietary Methyl-Mercury in Gammarus fossarum and Its Impact on the Amphipod Proteome

“…51 The NCBInr database was used to find the most probable protein homologue of the closest species to Gammarus fossarum for each protein with an e-value below 10 −10 . The Swissprot database was used to find the top 5 closest proteins in terms of sequence identity to define for each identified protein their biological processes and molecular functions as previously described, 52 selecting a bit score alignment above 20 and an e-value below 10 −4 . Differential Proteomics.…”

Possible teratogenic and adults abnormalities induced by insecticide pyriproxyfen on non-target organisms

“…Conversely, during the egg-hatching stages impairments revealed a significant death rate with M. viridis was seen with the same dose of PPF. Moreover, the exposure of the amphipod Gammarus fossarum to PPF through two consequent spermatogenesis cycles over a period of 2 weeks resulted in a noteworthy dose-dependent that influenced on spermatozoa's production and an inhibition of spermiogenesis during spermatid metamorphosis (Trapp et al, 2018). Tatarazako et al, (2003) stated that PPF treatment at 10-30 ng/L for Daphnia magna standard culture medium significantly induced reproduction toxicity with reduced number of offspring and changes in the sex ratio, and increased concentration at 1 μg/L induced male neonates (Ginjupalli and Baldwin, 2013) with altered lipid metabolism (Fuertes et al, 2019;Jordão et al, 2016).…”

“…During embryogenesis of zebrafish (Danio rerio), embryos were exposed once to a very high concentration of PPF (1670 µg PPF/L) and exhibited facial deformities among larvae, a high mortality rate, craniofacial defects, adverse behavioral effects, thinning of heart muscles, pericardial edema, hyperemia, and morphological defects with mandibular and eye deformities (Truong et al, 2016).…”