Data from: Dietary specialization in mutualistic acacia-ants affects relative abundance but not identity of host-associated bacteria
Data files
Aug 13, 2018 version files 379.13 MB
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BER0517_assembly.fa.gz
5.16 MB
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BER0554_assembly.fa.gz
6.95 MB
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contaminant_free.fa.gz
345.40 MB
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FPNIG.tar.gz
2.28 MB
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nitrogen_isotopes.xlsx
28.65 KB
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OTU_table.tsv
17.37 MB
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TPNIG.tar.gz
1.54 MB
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zotu_rep_seqs.fa.gz
388.79 KB
Abstract
Acacia-ant mutualists in the genus Pseudomyrmex nest obligately in acacia plants and, as we show through stable isotope analysis, feed at a remarkably low trophic level. Insects with diets such as these sometimes depend on bacterial symbionts for nutritional enrichment. We, therefore, examine the bacterial communities associated with acacia-ants in order to determine whether they host bacterial partners likely to contribute to their nutrition. Despite large differences in trophic position, acacia-ants and related species with generalized diets do not host distinct bacterial taxa. However, we find that a small number of previously undescribed bacterial taxa do differ in relative abundance between acacia-ants and generalists, including several Acetobacteraceae and Nocardiaceae lineages related to common insect-associates. Comparisons with an herbivorous generalist, a parasite that feeds on acacias, and a mutualistic species with a generalized diet show that trophic level is likely responsible for these small differences in bacterial community structure. While we did not experimentally test for a nutritional benefit to hosts of these bacterial lineages, metagenomic analysis reveals a Bartonella relative with an intact nitrogen-recycling pathway widespread across Pseudomyrmex mutualists and generalists. This taxon may be contributing to nitrogen enrichment of its ant hosts through urease activity and, concordant with an obligately host-associated lifestyle, appears to be experiencing genome-wide relaxed selection. The lack of distinctiveness in bacterial communities across trophic level in this group of ants shows a remarkable ability to adjust to varied diets, possibly with assistance from these diverse ant-specific bacterial lineages.