Abraham Brouwer

Nonribosomal peptide synthetases (NRPSs) are a class of cytosolic enzymes that synthesize a range of bio-active secondary metabolites including antibiotics and siderophores. They are widespread among both prokaryotes and eukaryotes but are considered rare among animals. Recently, several novel NRPS genes have been described in nematodes, schistosomes, and arthropods, which led us to investigate how prevalent NRPS genes are in the animal kingdom. We screened 1059 sequenced animal genomes and showed that NRPSs were present in 7 out of the 19 phyla analyzed. A phylogenetic analysis showed that the identified NRPSs form clades distinct from other adenylate-forming enzymes that contain similar domains such as fatty acid synthases. NRPSs show a remarkably scattered distribution over the animal kingdom. They are especially abundant in rotifers and nematodes. In rotifers, we found a large variety of domain architectures and predicted substrates. In the nematode Plectus sambesii, we identified the beta-lactam biosynthesis genes L-δ-(α-aminoadipoyl)-L-cysteinyl-D-valine synthetase, isopenicillin N synthase, and deacetoxycephalosporin C synthase that catalyze the formation of beta-lactam antibiotics in fungi and bacteria. These genes are also present in several species of Collembola, but not in other hexapods analyzed so far. In conclusion, our survey showed that NRPS genes are more abundant and widespread in animals than previously known.

Horizontal gene transfer (HGT) is defined as the acquisition by an organism of hereditary material from a phylogenetically unrelated organism. This process is mostly observed among bacteria and archaea, and considered less likely between microbes and multicellular eukaryotes. However, recent studies provide compelling evidence of the evolutionary importance of HGT in eukaryotes, driving functional innovation. Here, we study an HGT event in Folsomia candida (Collembola, Hexapoda) of a carbohydrate-active enzyme homologous to glycosyl hydrase group 43 (GH43). The gene encodes an N-terminal signal peptide, targeting the product for excretion, which suggests that it contributes to the diversity of digestive capacities of the detritivore host. The predicted α-L-arabinofuranosidase shows high similarity to genes in two other Collembola, an insect and a tardigrade. The gene was cloned and expressed in Escherichia coli using a cell-free protein expression system. The expressed protein showed activity against p-nitrophenyl-α-L-arabinofuranoside. Our work provides evidence for functional activity of an HGT gene in a soil-living detritivore, most likely from a bacterial donor, with genuine eukaryotic properties, such as a signal peptide. Co-evolution of metazoan GH43 genes with the Panarthropoda phylogeny suggests the HGT event took place early in the evolution of this ecdysozoan lineage.

The anabolic androgenic steroids (AAS) are the most frequently consumed performance enhancing drugs (PED) in sports. In the anti-doping field, the detection of AAS is carried out by the analysis of the athlete’s urine using methodologies based on liquid/gas chromatography-mass spectrometry. Unfortunately, the detection of unknown compounds is not possible. BDS’s AR CALUX^® bio detection technology was studied as an indirect method to detect the administration of a single dose of testosterone (T). Twelve T and placebo single dose administered men volunteers underwent a triple-blind crossover clinical trial. The UGT2B17 deletion was present among the volunteers and evenly distributed in heterozygous (ins/del), wild-type homozygous (ins/ins), and mutated homozygous (del/del) groups. A significant statistical difference in terms of bioluminescence was observed after the testosterone (T) administration for the three types of polymorphic groups. The ratio of means between the pre- and post-T administration periods, depending on the type of polymorphism, was in group ins/ins 3.31 (CI. 95%: 2.07–5.29), group ins/del 4.15 (CI 95%: 3.05–5.67), and group del/del 2.89 (CI 95%: 2.42–3.46). The results of the study are very promising, as they may offer us the possibility of designing a detection approach that, based on intra-individual monitoring of androgenic values, in the UGT2B17 deletion type.