PMC

Representation of human skin. The topographical surface of human skin is irregular and consists of multiple skin appendageal structures including hair follicles, sebaceous (oil) glands, and sweat glands and ducts. Each of the skin appendages provides a potential niche for skin bacteria. The external communication of the skin with the terrestrial environment and the heterogeneity of the appendageal invaginations contribute to the diversity of the skin microbiome.

Schematic view of 16S ribosomal RNA gene-based bacterial sequencing workflow. The 16S ribosomal RNA gene is universal among prokaryotes and can be used for phylotyping bacterial sequences. This diagram shows the process from collecting a skin sample to DNA sequencing and analysis used in many skin microbiome studies.

Heterogeneity and pattern of distribution of the skin microbiome for over 20 skin sites. Each pie chart represents the relative abundance of different bacterial phyla at the indicated sites. Bacterial diversity varies among the many skin sites. Sites sharing physiologic features such as oily skin have greater similarities in the bacterial composition. Data derived primarily from []** with additional data from []*.