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Abstract. Decaying vegetation was determined to be a potentially important source ofatmospheric ice nucleation particles (INPs) in the early 1970s. The bacteriumPseudomonas syringae was the first microorganism with ice nucleationactivity (INA) isolated from decaying leaf litter in 1974. However, the icenucleation characteristics of P. syringae are not compatible withthe characteristics of leaf litter-derived INPs since the latter were foundto be sub-micron in size, while INA of P. syringae depends on muchlarger intact bacterial cells. Here we determined the cumulative icenucleation spectrum and microbial community composition of the historic leaflitter sample 70-S-14 collected in 1970 that conserved INA for 48 years. Themajority of the leaf litter-derived INPs were confirmed to be sub-micron insize and to be sensitive to boiling. Culture-independent microbial communityanalysis only identified Pseudomonas as potential INA.Culture-dependent analysis identified one P. syringae isolate, twoisolates of the bacterial species Pantoea ananatis, and one fungalisolate of Mortierella alpina as having INA among 1170 bacterialcolonies and 277 fungal isolates, respectively. Both Pa. ananatisand M. alpina are organisms that produce heat-sensitive sub-micronINPs. They are thus both likely sources of the INPs present in sample 70-S-14and may represent important terrestrial sources of atmospheric INPs, aconclusion that is in line with other recent results obtained in regard toINPs from soil, precipitation, and the atmosphere.
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Draft Genome Sequence of Mortierella alpina Strain LL118, Isolated from an Aspen (Populus tremuloides) Leaf Litter Sample
ABSTRACT Mortierella alpina is a filamentous fungus commonly associated with soil and is one of very few fungal species known to include strains with ice nucleation activity. Here, we report the draft genome sequence of the ice nucleation-active M. alpina strain LL118, isolated from aspen leaf litter collected in Alberta, Canada.
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- Award ID(s):
- 1754721
- PAR ID:
- 10321221
- Editor(s):
- Bruno, Vincent
- Date Published:
- Journal Name:
- Microbiology Resource Announcements
- Volume:
- 10
- Issue:
- 47
- ISSN:
- 2576-098X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1128/MRA.00864-21
