Biology subjects

Lorang, C.

Publications and source records attributed to Lorang, C..

3 recordsLinked to original sources

bioRxiv2025

Lead exposure positively affects coccidia abundance in feral pigeons (Columba livia)

O_LIIn urban environments, organisms are exposed to high levels of pollutants, including trace metals, whose concentrations can be increased by anthropogenic activities. Numerous studies have shown the toxic effects of pollutants on exposed organisms. However, due to their life within the host, parasites can also be affected by exposure to these pollutants. Overall, previous correlative findings reveal that the effects of parasite exposure to pollutants through the host can vary, from positive to negative, highlighting the complexity of host-parasite-environment interactions in relation to pollution. C_LIO_LIIn this study, we experimentally tested whether lead exposure affects the abundance of ecto-, meso-, and endoparasites in wild pigeons (Columba livia), which host a wide variety of parasites and are naturally exposed to trace metals in urban environments. As we had previously reported the toxic effects of lead on the immune system of pigeons, we expected lead exposure to be indirectly beneficial for the parasites. C_LIO_LITo test this, we used a sample of wild pigeons captured in Paris, half of which were experimentally exposed to lead concentrations similar to those found in Paris. We then measured the abundance of several parasites: blood parasites (hemosporidian parasites), ectoparasites (Columbicola columbae and Campanulote compar), coccidia and helminths. Additionally, we measured the intensity of the pigeons antiparasitic behavioral response (grooming) through behavioral analyses. C_LIO_LIOur results did not reveal toxic effects of lead exposure on the parasites. On the contrary, we found positive effects of this exposure on coccidia abundance in male pigeons. This result could be explained by a toxic effect of lead on the hosts antiparasitic immune strategy, making the hosts less hostile to parasites. However, we found no effect of lead exposure on the abundance of lice, blood parasites and helminths. This could be explained by the lack of impact of lead exposure on grooming antiparasitic activity in our experiment, and by seasonal variations in the activity of blood parasite vectors, which may have masked potential effects of our treatment. C_LIO_LIIn conclusion, our study highlights the importance of considering the host environment, particularly pollutants, to understand parasite dynamics. C_LI

ecology↗

bioRxiv2025

Pectobacterium versatile beta-lactamase, a common good of the soft rot Pectobacteriaceae (SRP) species complex

Little is known about the role of antibiotics and associated resistance in microbial ecosystems in the absence of clinical antibiotic pressure. The Soft Rot Pectobacteriaceae (SRP) species complex, which comprises 37 bacterial species that are collectively responsible for the severe rotting of many crops, is an interesting model to analyse the role of {beta}-lactam and {beta}-lactamases in natural ecosystems. In particular, within this complex, most Pectobacterium versatile strains harbour a {beta}-lactamase called BlaPEC-1. The aim of our work was to analyse the role of BlaPEC-1 during infection. To this end, two blaPEC-1-deleted strains were constructed and compared with their wild-type counterparts in vitro and in potato tuber infections. In vitro, the BlaPEC-1 {beta}-lactamase enables P. versatile to resist ampicillin or carbapenem produced by Pectobacterium brasiliense. In mono-infections on potato tubers, blaPEC-1-deleted strains were unaffected in terms of virulence, fitness or association with commensal bacteria. In mixed infections, the BlaPEC-1 {beta}-lactamase proved necessary for the coexistence of P. versatile with the carbapenem-producing strain, and also for the protection of carbapenem-sensitive strains both in vitro and in planta. Interestingly, in planta protection was observed even if the blaPEC-1 gene was repressed and bacteria expressing BlaPEC-1 were in the minority within the symptom. These results indicate that BlaPEC-1 exerts a true {beta}-lactamase function during the infection process and acts as a public good of the SRP species complex. Finally, our results highlight the important role of {beta}-lactamase in maintaining of strains diversity in natural ecosystem. Statements relating to our ethics and integrity policiesThe data shown in this paper are available within the article and supplementary materials. The funding of the ANR, ANR-19-CE35-0016-03, is acknowledged. The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication. The authors declare that there are no conflicts of interest. All applicable local, national and international regulations and conventions, as well as normal scientific ethical practices, were followed in the preparation of this work. This manuscript has not been previously or simultaneously published or submitted elsewhere and was critically reviewed and approved by all co-authors before submission. The CRediT of all authors is provided.

microbiology↗

bioRxiv2021

Mouse Organ Specific Proteins and Functions

Organ specific proteins (OSPs) possess great medical potentials both in clinics and in biomedical research. Applications of them -- such as alanine transaminase, aspartate transaminase, and troponins -- in clinics have raised certain concerns of their organ specificity. The dynamics and diversity of protein expression in heterogeneous human population are well known, yet their effects on OSPs are less addressed. Here we use mouse as a model and implemented a scheme of breadth study to examine the pan-organ proteome for potential variations of organ specificity in different genetic backgrounds. Using reasonable resources, we generated pan-organ proteomes of four in-bred mouse strains. The results revealed a large diversity that is more profound among OSPs than the overall proteomes. We defined a robustness score to quantify such variation and derived three sets of OSPs with different stringencies. In the meantime, we found that the enriched biological functions of OSPs are also organ specific that are sensitive and useful to assess the quality of OSPs. We hope our breadth study can open doors to explore the molecular diversity and dynamics of organ specificity at the protein level.

genomics↗