Within the framework of the ‘Comparative genomics of early
diverging terrestrial fungi and their bacterial
endosymbionts’ CSP project, we are exploring interactions and
evolutionary histories of early diverging lineages of terrestrial
fungi and their endobacteria (Desirò et al. 2018; Uehling et
al. 2017). Towards this goal, we are sequencing metagenomes and
metatranscriptomes of a diverse panel of fungi in Mucoromycota that
host endohyphal bacteria.
Mortierella is a large genus of fungi within
Mucoromycota, formally classified as zygomycetes. These fungi are
industrially important given their unique fatty acid and lipid
metabolism, which is of interest for biofuel production.
Mortierella species are distributed globally and are
frequently isolated and detected in soils and plant rhizospheres.
Many species grow rapidly, in part owing to their coenocytic
mycelium that has occasional septa and frequent anastomosis.
Mortierella are considered to be haploid and
heterothallic, although some isolates have been reported to be
homothallic (Gams et al. 1972). Of particular interest,
Mortierella species can harbor endobacteria within their
cells, which affect the fungal host's growth and physiology.
Mortierella minutissima AD051 was isolated from a spruce
rhizosphere soil sample collected in Laingsburg, Michigan, USA.
This species grows rapidly, producing a rosette colony morphology
characteristic of many Mortierella species (Figure 1). It
also produces abundant aerial hyphae and sporangiola that contain a
few spores. A
novel endobacterium closely related to Mycoavidus
cysteinexigens (Ohshima et al. 2016) was identified within the
mycelium of M. minutissima AD051.
References:
Desirò A, Hao Z, Liber JA, Benucci GM, Lowry D, Roberson R,
Bonito G. 2018. Mycoplasma-related endobacteria within
Mortierellomycotina fungi: diversity, distribution and functional
insights into their lifestyle. The ISME journal. DOI:
10.1038/s41396-018-0053-9
Gams, W., Chiu-Yuan Chien, and K. H. Domsch. 1972. Zygospore
formation by the heterothallic Mortierella elongata and a
related homothallic species, M. epigama sp.nov.. Transactions of
the British Mycological Society 58 (1): 5–IN2.
Ohshima S, Sato Y, Fujimura R, Takashima Y, Hamada M, Nishizawa
T, Narisawa K, Ohta H. 2016. Mycoavidus cysteinexigens
gen. nov., sp. nov., an endohyphal bacterium isolated from a soil
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Uehling J, Gryganskyi A, Hameed K, Tschaplinski T, Misztal PK, Wu
S, Desirò A, Vande Pol N, Du Z, Zienkiewicz A, Zienkiewicz
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