Evolutionary Genomics of Bacterial Endosymbionts: From Mutualism to Parasitism

Dear Colleagues,

Bacterial endosymbionts are ubiquitous across the tree of life, forming intimate associations with a wide range of hosts, including insects, marine invertebrates, and even vertebrates. These relationships span a dynamic spectrum—from mutualism to parasitism—and play pivotal roles in shaping host biology, ecology, and evolution.

Despite their significance, the study of endosymbionts presents unique challenges. Many are obligate intracellular organisms, often unculturable outside their hosts. However, advances in genomic technologies—such as whole-genome sequencing, comparative and population genomics, phylogenomics, and co-phylogenetic analyses—have opened new avenues for exploring the complexity of these associations.

This Special Issue invites original research articles and comprehensive reviews that delve into the evolutionary genomics of bacterial endosymbionts, with a focus on understanding the molecular and evolutionary mechanisms underlying transitions along the mutualism–parasitism continuum. We are particularly interested in studies that

• Explore genome reduction, functional specialization, and metabolic interdependence;
• Investigate host–symbiont co-evolution and co-phylogeny;
• Examine the evolutionary origins and transitions between mutualism, commensalism, amensalism, and parasitism;
• Utilize experimental evolution or synthetic biology to model symbiotic interactions;
• Highlight the ecological and evolutionary consequences of symbiosis for both partners;
• Explore other topics aligned with the theme of this Special Issue.

Dr. Amit Sinha
Guest Editor

Manuscript Submission Information

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