This project aims to undertake global surveys of microbial diversity in a range of free-living and host-associated communities. The importance of the project is that it will provide a comparison of microbial diversity in a range of habitats and provide a platform to underpin many studies of community assembly, diversity, etc.
Bacteria thrive on and within the human body. One of the largest
human-associated microbial habitats is the skin surface, which
harbors large numbers of bacteria that can have important effects
on health. We examined the palmar surfaces of the dominant and
nondominant hands of 51 healthy young adult volunteers to
characterize bacterial diversity on hands and to assess its variability
within and between individuals. We used a novel pyrosequencing-
based method that allowed us to survey hand surface bacterial
communities at an unprecedented level of detail. The diversity of
skin-associated bacterial communities was surprisingly high; a
typical hand surface harbored >150 unique species-level bacterial
phylotypes, and we identified a total of 4,742 unique phylotypes
across all of the hands examined. Although there was a core set of
bacterial taxa commonly found on the palm surface, we observed
pronounced intra- and interpersonal variation in bacterial community
composition: hands from the same individual shared only 17%
of their phylotypes, with different individuals sharing only 13%.
Women had significantly higher diversity than men, and community
composition was significantly affected by handedness, time
since last hand washing, and an individual's sex. The variation
within and between individuals in microbial ecology illustrated by
this study emphasizes the challenges inherent in defining what
constitutes a "healthy" bacterial community; addressing these
challenges will be critical for the International Human Microbiome
Project.
Bacterial 16S ribosomal RNA sequences have been deposited in the Short Read Archive. Less...