Biology subjects

Grapputo, A.

Publications and source records attributed to Grapputo, A..

3 recordsLinked to original sources

bioRxiv2026

Drosophila melanogaster as a platform for the functional expression of engineered PET-degrading enzymes

Insects offer promising opportunities for organic waste bioconversion; however, they cannot efficiently degrade synthetic polymers such as polyethylene terephthalate (PET). Here, we generated transgenic Drosophila melanogaster lines to express in vitro-evolved variants of two PET-degrading enzymes with distinct biochemical properties: an engineered Ideonella sakaiensis PETase variant (TS-{Delta}IsPET) and a leaf-branch compost cutinase variant (TA-{Delta}LCC). Both enzymes, fused to a Drosophila gut-derived secretory signal, were produced and secreted by both Drosophila cultured S2R+ cells and transgenic larvae. Both enzymes were glycosylated upon secretion, a post-translational modification that did not abolish their catalytic activity. Notably, TA-{Delta}LCC displayed [~]6-fold higher esterase activity than TS-{Delta}IsPET in larval extracts and TA-{Delta}LCC-containing extracts depolymerised PET nanoparticles in vitro under enzyme-favourable conditions. Transgenic flies showed normal development, fertility and survival. Morphological and biochemical analysis confirmed that TA-{Delta}LCC expression did not alter midgut structure and function. Together, these results establish Drosophila melanogaster as a model for functional expression and comparative evaluation of engineered PET-degrading enzymes and identify TA-{Delta}LCC as a promising candidate for exploitation in insect species relevant to plastic contaminated waste bioconversion. HighlightsO_LITransgenic D. melanogaster enables in vivo study of engineered PET enzymes C_LIO_LIEngineered TS-{Delta}IsPET and TA-{Delta}LCC are functional in larval extracts C_LIO_LITA-{Delta}LCC was selected for PET nanoparticle assays due to higher pNPA activity C_LIO_LID. melanogaster model enables comparative evaluation of PET-degrading enzymes C_LI

biochemistry↗

bioRxiv2023

Sperm production is negatively associated with muscle and sperm telomere length in a highly polyandrous species

Life history theory suggests that aging is one of the costs of reproduction. Accordingly, a higher reproductive allocation is expected to increase the deterioration of both the somatic and the germinal lines through enhanced telomere attrition. In most species, males reproductive allocation mainly regards traits that increase mating and fertilization success, i.e. sexually selected traits. In the current study, we tested the hypothesis that a higher investment in sexually selected traits is associated with a reduced telomere length in the guppy (Poecilia reticulata), an ectotherm species characterized by strong pre- and postcopulatory sexual selection. We first measured telomere length in both the soma and the sperm over the course of guppys lifespan to see if there was any variation in telomere length associated with age. Secondly, we investigated whether a greater expression of pre- and postcopulatory sexually selected traits is linked to shorter telomere length in both the somatic and the sperm germinal lines, and in young and old males. We found that telomeres lengthened with age in the somatic tissue, but there was no age-dependent variation in telomere length in the sperm cells. Telomere length in guppies was significantly and negatively correlated with sperm production in both tissues and life stages considered in this study. Our findings indicate that telomere erosion in male guppies is more strongly associated with their reproductive investment (sperm production) rather than their age, suggesting a trade-off between reproduction and maintenance is occurring at each stage of males life in this species.

molecular biology↗

bioRxiv2017

A model species for agricultural pest genomics: the genome of the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

The Colorado potato beetle is one of the most challenging agricultural pests to manage. It has shown a spectacular ability to adapt to a variety of solanaceaeous plants and variable climates during its global invasion, and, notably, to rapidly evolve insecticide resistance. To examine evidence of rapid evolutionary change, and to understand the genetic basis of herbivory and insecticide resistance, we tested for structural and functional genomic changes relative to other arthropod species using genome sequencing, transcriptomics, and community annotation. Two factors that might facilitate rapid evolutionary change include transposable elements, which comprise at least 17% of the genome and are rapidly evolving compared to other Coleoptera, and high levels of nucleotide diversity in rapidly growing pest populations. Adaptations to plant feeding are evident in gene expansions and differential expression of digestive enzymes in gut tissues, as well as expansions of gustatory receptors for bitter tasting. Surprisingly, the suite of genes involved in insecticide resistance is similar to other beetles. Finally, duplications in the RNAi pathway might explain why Leptinotarsa decemlineata has high sensitivity to dsRNA. The L. decemlineata genome provides opportunities to investigate a broad range of phenotypes and to develop sustainable methods to control this widely successful pest.

genomics↗