TY  - JOUR
A1  - Costea, Paul I.
A1  - Coelho, Louis Pedro
A1  - Sunagawa, Shinichi
A1  - Munch, Robin
A1  - Huerta-Cepas, Jaime
A1  - Forslund, Kristoffer
A1  - Hildebrand, Falk
A1  - Kushugulova, Almagul
A1  - Zeller, Georg
A1  - Bork, Peer
T1  - Subspecies in the global human gut microbiome
JF  - Molecular Systems Biology
N2  - Population genomics of prokaryotes has been studied in depth in only a small number of primarily pathogenic bacteria, as genome sequences of isolates of diverse origin are lacking for most species. Here, we conducted a large‐scale survey of population structure in prevalent human gut microbial species, sampled from their natural environment, with a culture‐independent metagenomic approach. We examined the variation landscape of 71 species in 2,144 human fecal metagenomes and found that in 44 of these, accounting for 72% of the total assigned microbial abundance, single‐nucleotide variation clearly indicates the existence of sub‐populations (here termed subspecies). A single subspecies (per species) usually dominates within each host, as expected from ecological theory. At the global scale, geographic distributions of subspecies differ between phyla, with Firmicutes subspecies being significantly more geographically restricted. To investigate the functional significance of the delineated subspecies, we identified genes that consistently distinguish them in a manner that is independent of reference genomes. We further associated these subspecies‐specific genes with properties of the microbial community and the host. For example, two of the three Eubacterium rectale subspecies consistently harbor an accessory pro‐inflammatory flagellum operon that is associated with lower gut community diversity, higher host BMI, and higher blood fasting insulin levels. Using an additional 676 human oral samples, we further demonstrate the existence of niche specialized subspecies in the different parts of the oral cavity. Taken together, we provide evidence for subspecies in the majority of abundant gut prokaryotes, leading to a better functional and ecological understanding of the human gut microbiome in conjunction with its host.
KW  - biology
KW  - genetic variation
KW  - metagenomics
KW  - microbiome
KW  - population structure
KW  - prokaryotic subspecies
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172674
VL  - 13
IS  - 12
ER  - 
TY  - JOUR
A1  - Hartke, Juliane
A1  - Sprenger, Philipp P.
A1  - Sahm, Jacqueline
A1  - Winterberg, Helena
A1  - Orivel, Jérôme
A1  - Baur, Hannes
A1  - Beuerle, Till
A1  - Schmitt, Thomas
A1  - Feldmeyer, Barbara
A1  - Menzel, Florian
T1  - Cuticular hydrocarbons as potential mediators of cryptic species divergence in a mutualistic ant association
JF  - Ecology and Evolution
N2  - Upon advances in sequencing techniques, more and more morphologically identical organisms are identified as cryptic species. Often, mutualistic interactions are proposed as drivers of diversification. Species of the neotropical parabiotic ant association between Crematogaster levior and Camponotus femoratus are known for highly diverse cuticular hydrocarbon (CHC) profiles, which in insects serve as desiccation barrier but also as communication cues. In the present study, we investigated the association of the ants’ CHC profiles with genotypes and morphological traits, and discovered cryptic species pairs in both genera. To assess putative niche differentiation between the cryptic species, we conducted an environmental association study that included various climate variables, canopy cover, and mutualistic plant species. Although mostly sympatric, the two Camponotus species seem to prefer different climate niches. However in the two Crematogaster species, we could not detect any differences in niche preference. The strong differentiation in the CHC profiles may thus suggest a possible role during speciation itself either by inducing assortative mating or by reinforcing sexual selection after the speciation event. We did not detect any further niche differences in the environmental parameters tested. Thus, it remains open how the cryptic species avoid competitive exclusion, with scope for further investigations.
KW  - environmental association
KW  - integrative taxonomy
KW  - niche differentiation
KW  - population structure
KW  - sexual selection
KW  - speciation
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227857
VL  - 9
ER  -