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Title: Shotgun metagenomics and microscopy indicate diverse cyanophytes, other bacteria, and microeukaryotes in the epimicrobiota of a northern Chilean wetland Nostoc (Cyanobacteria)

ProkaryoticNostoc, one of the world's most conspicuous and widespread algal genera (similar to eukaryotic algae, plants, and animals) is known to support a microbiome that influences host ecological roles. Past taxonomic characterizations of surface microbiota (epimicrobiota) of free‐livingNostocsampled from freshwater systems employed 16S rRNA genes, typically amplicons. We compared taxa identified from 16S, 18S, 23S, and 28S rRNA gene sequences filtered from shotgun metagenomic sequence and used microscopy to illuminate epimicrobiota diversity forNostocsampled from a wetland in the northern Chilean Altiplano. Phylogenetic analysis and rRNA gene sequence abundance estimates indicated that the host was related toNostoc punctiformePCC 73102. Epimicrobiota were inferred to include 18 epicyanobacterial genera or uncultured taxa, six epieukaryotic algal genera, and 66 anoxygenic bacterial genera, all having average genomic coverage ≥90X. The epicyanobacteriaGeitlerinemia,Oscillatoria,Phormidium, and an uncultured taxon were detected only by 16S rRNA gene;GloeobacterandPseudanabaenawere detected using 16S and 23S; andPhormididesmis,Neosynechococcus,Symphothece,Aphanizomenon,Nodularia,Spirulina,Nodosilinea,Synechococcus,Cyanobium, andAnabaena(the latter corroborated by microscopy), plus two uncultured cyanobacterial taxa (JSC12, O77) were detected only by 23S rRNA gene sequences. Three chlamydomonad and two heterotrophic stramenopiles genera were inferred from 18S; the streptophyte green algaChaetosphaeridium globosumwas detected by microscopy and 28S rRNA genes, but not 18S rRNA genes. Overall, >60% of epimicrobial taxa were detected by markers other than 16S rRNA genes. Some algal taxa observed microscopically were not detected from sequence data. Results indicate that multiple taxonomic markers derived from metagenomic sequence data and microscopy increase epimicrobiota detection.

 
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NSF-PAR ID:
10453969
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Journal of Phycology
Volume:
57
Issue:
1
ISSN:
0022-3646
Page Range / eLocation ID:
p. 39-50
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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