Parasites and their (endo)symbiotic microbes

Abstract

Thanks to modern molecular biology methods, our understanding of the impact of (endo) symbiotic bacteria on parasitic protists and helminths is growing fast. In this issue, 9 papers have been brought together that describe various facets of the relationships between these microorganisms, reveal their range and high frequency, as well as their capacity to create novel biological complexity. Comparative analyses of these host-endosymbiont interactions indicate that there may be no discrete types of relationships but rather a continuum ranging from a dispensable endosymbiont minimally integrated within the host cell to organelles, such as mitochondria and plastids that evolved into an indispensable, deeply integrated components of the cell. We hope that this series of studies on parasites and (endo)symbiotic bacteria will increase awareness about these relationships and their representation in microbial ecology models.

Parasite microbiome project: Grand challenges

“…An improved understanding of underlying molecular mechanisms and evolutionary patterns that explain interindividual, temporal, and geographic variation in the outcomes of parasitic infections is much needed [6–9]. There is an increasing recognition of the potential for host- and parasite-associated microbiota―endo- and/or ectosymbiotic archaea, bacteria, viruses, and micro-eukaryotes―to influence and shape host–parasite interactions [10]. In the past few years, the concept of individuality has given way to that of “holobiont” with the recognition that each organism is a composite of organisms [11–14] (Fig 1, Box 1).…”

A New Model Trypanosomatid, Novymonas esmeraldas : Genomic Perception of Its “ Candidatus Pandoraea novymonadis” Endosymbiont

“…The more extensively studied endosymbiosis is the one in the subfamily Strigomonadinae that coevolved for a long time with “ Ca. Kinetoplastibacterium” This has significantly influenced several morphological features of their hosts, such as the packaging of kinetoplast DNA, the length of the paraflagellar rod, and the extent to which the mitochondrion penetrates the layer of subpellicular microtubules ( 8 , 18 , 69 ). These endosymbionts have a reduced peptidoglycan layer, coordinate their division with that of the host, and are transmitted vertically ( 70 ).…”

The immunology of parasite infections: Grand challenges

“…In addition to the host microbiota, parasite-associated microbiota also shapes the host immune response and the pathological outcome to disease (Ives et al, 2011;Yurchenko and Lukes, 2018). However, despite the identification of the Wolbachia endosymbiont of filarial nematodes more than 20 years ago (Williams et al, 2000), only a handful of parasite species have had their associated microbiome characterized (Dheilly et al, 2019).…”