Exception violated: the arbuscular mycorrhizal fungi Gigaspora rosea and G. margarita host culturable and functionally diverse endospore bacteria

DJOTAN, Akotchiffor Kevin Geoffroy

doi:10.51094/jxiv.3901

##article.authors##

DJOTAN, Akotchiffor Kevin Geoffroy The University of Tokyo

DOI:

https://doi.org/10.51094/jxiv.3901

キーワード:

Arbuscular Mycorrhizal Fungi、 Gigaspora Endospore Bacteria、 Morphology and Functions

抄録

While bacteria are commonly hosted in over 10 genera of arbuscular mycorrhizal fungi (AMF) including Gigaspora, studies have shown that all examined Gigaspora species host endospore bacteria, with the sole exception of G. rosea. Because of trait variability among conspecific AMF of different origins, we hypothesized that the non-investigated forest-derived G. rosea LFB-4 and G. margarita LFB-A1 could host endospore bacteria. We severely surface-decontaminated and crushed 10 - 20 spores to culture their potential endospore bacteria. The isolated bacteria were identified based on morphological, molecular, and phylogenetic analyses as well as enzymatic activities. Both AMF species hosted culturable and functionally diverse endospore bacteria belonging to five genera. Streptomyces was isolated from the two AMF, Paraburkholderia and Paenibacillus from G. rosea only, and the previously never isolated Chryseobacterium and Mycolicibacterium from G. margarita only. Glycosidases, peptide, ester, and phosphoric hydrolases activities in the isolated bacteria depended on the host AMF, highlighting their nutrient cycling potentials. Here, we updated endospore bacterial composition in G. rosea and G. margarita and cleared the exception that G. rosea lacks them. AMF may carry all the required functional groups of microbiomes inside their spores, into the roots of their host plants in various environments.

利益相反に関する開示

The authors declare no conflicts of interest. This work was completed while the first author was affiliated with Mie University but submitted while affiliated with Okinawa Institute of Science and Technology.

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