The evolution and changing ecology of the African hominid oral microbiome.

The oral microbiome plays key roles in human biology, health, and disease, but little is known about the global diversity, variation, or evolution of this microbial community. To better understand the evolution and changing ecology of the human oral microbiome, we analyzed 124 dental biofilm metagenomes from humans, including Neanderthals and Late Pleistocene to present-day modern humans, chimpanzees, and gorillas, as well as New World howler monkeys for comparison. We find that a core microbiome of primarily biofilm structural taxa has been maintained throughout African hominid evolution, and these microbial groups are also shared with howler monkeys, suggesting that they have been important oral members since before the catarrhine-platyrrhine split ca. 40 Mya. However, community structure and individual microbial phylogenies do not closely reflect host relationships, and the dental biofilms of Homo and chimpanzees are distinguished by major taxonomic and functional differences. Reconstructing oral metagenomes from up to 100 thousand years ago, we show that the microbial profiles of both Neanderthals and modern humans are highly similar, sharing functional adaptations in nutrient metabolism. These include an apparent Homo-specific acquisition of salivary amylase-binding capability by oral streptococci, suggesting microbial coadaptation with host diet. We additionally find evidence of shared genetic diversity in the oral bacteria of Neanderthal and Upper Paleolithic modern humans that is not observed in later modern human populations. Differences in the oral microbiomes of African hominids provide insights into human evolution, the ancestral state of the human microbiome, and a temporal framework for understanding microbial health and disease

2000-year-old pathogen genomes reconstructed from metagenomic analysis of Egyptian mummified individuals

BACKGROUND: Recent advances in sequencing have facilitated large-scale analyses of the metagenomic composition of different samples, including the environmental microbiome of air, water, and soil, as well as the microbiome of living humans and other animals. Analyses of the microbiome of ancient human samples may provide insights into human health and disease, as well as pathogen evolution, but the field is still in its very early stages and considered highly challenging. - RESULTS: The metagenomic and pathogen content of Egyptian mummified individuals from different time periods was investigated via genetic analysis of the microbial composition of various tissues. The analysis of the dental calculus’ microbiome identified Red Complex bacteria, which are correlated with periodontal diseases. From bone and soft tissue, genomes of two ancient pathogens, a 2200-year-old Mycobacterium leprae strain and a 2000-year-old human hepatitis B virus, were successfully reconstructed. - CONCLUSIONS: The results show the reliability of metagenomic studies on Egyptian mummified individuals and the potential to use them as a source for the extraction of ancient pathogen DNA.Background Results - Sample information and dating - General metagenomic assessment - Mycobacterium leprae (individual Abusir1630) - Hepatitis B virus (individual Abusir1543) - Oral microbiome assessment Discussion Conclusions Methods - Sample extraction and radiocarbon dating - Sample extraction and library preparation - Metagenomic screening - Authentication of ancient DNA - Content of endogenous DNA (SourceTracker2) - Data processing of sample Abusir1630b (M. leprae) -- Read processing, mapping, and variant calling -- SNP typing -- Anthropological analysis -- Phylogeny -- Beast analysis -- Temporal signal - Data processing individual Abusir1543 (hepatitis B virus) -- Read processing, mapping, and variant calling -- Phylogeny -- Recombination analysis -- Beast analysis -- Temporal signa

A low-voltage low-power 0.25 µm CMOS ADSL analog front-end IC

A 0.12 µm 2.5V CMOS analog front-end IC for an ADSL system is presented. The IC contains all analog functions including gain-controlled transmit and receive amplifiers, highly linear continuous-time low pass filtering including on-chip automatic tuning. 8.8Ms/s ADC and DAC as well as a crystal driver and a DAC-controlled VCO. The IC has been realized in a mixed-signal 0.25 µm triple-well CMOS technology, with a chip area of 25 mm², and a power consumption of only 300mW using 2.5V supply