Symbiosis between microbes and insects has been raised as a promising area for understanding biological implications of microbe-host interactions. Among them, the association between fungi and bark beetles has been generally recognized as essential for the bark beetle ecology. However, many works investigating bark beetle bacterial communities and their functions usually meet in a common finding: Pseudomonas is a broadly represented genus within this holobiont and it may provide beneficial roles to its host. Thus, we aimed to review available research on this microbe-host interaction and point out the probable relevance of Pseudomonas strains for these insects, in order to guide future research toward a deeper analysis of the importance of these bacteria for the beetle's life cycle.

Associated Research Unit of Plant Microorganism Interaction USAL CSIC 37008 Salamanca Spain

Department of Botany Faculty of Science Charles University 128 01 Prague Czech Republic

Institute of Microbiology of the Czech Academy of Sciences Vídeňská 1083 142 20 Prague Czech Republic

Microbiology and Genetics Department University of Salamanca 37007 Salamanca Spain

Spanish Portuguese Institute for Agricultural Research Villamayor 37185 Salamanca Spain

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Comparative metagenomic study unveils new insights on bacterial communities in two pine-feeding Ips beetles (Coleoptera: Curculionidae: Scolytinae)

New insight into the bark beetle ips typographus bacteriome reveals unexplored diversity potentially beneficial to the host

Comparative Genomics of the Genus Pseudomonas Reveals Host- and Environment-Specific Evolution