Comprehensive skin microbiome analysis reveals the uniqueness of human skin and evidence for phylosymbiosis within the class Mammalia

Abstract

SignificanceSkin forms a critical protective barrier between a mammal and its external environment. Baseline data on the mammalian skin microbiome elucidates which microorganisms are found on healthy skin and provides insight into mammalian evolutionary history. To our knowledge, this study represents the largest existing mammalian skin microbiome survey. Our findings demonstrate that human skin is distinct, not only from other Primates, but from all 10 mammalian orders sampled. Identifying significant similarities between branching of mammalian phylogenetic trees and relatedness trees for their corresponding microbial communities raises the possibility that mammals have experienced coevolution between skin microbiota and their corresponding host species.

An introduction to phylosymbiosis

“…Microbiome distinguishability, or the characteristic of being able to significantly differentiate microbial communities of host lineages under evaluation, is a prerequisite for phylosymbiosis and should be tested before evaluating the phylosymbiosis prediction that more similar host species harbour more similar microbiomes [20,23,[51][52][53]. Microbiome distinguishability can be visualized from beta diversity data and categorical sample grouping data using ordination plots, such as principal coordinate analysis (PCoA) and non-metric multidimensional scaling (NMDS) plots [56].…”

“…The determination of phylosymbiosis relies on evaluating a significant association between host phylogenetic relationships and host-associated microbial community distances. To this end, topological congruency tests directly compare topologies of a host phylogenetic tree and a microbiome dendrogram [23,42,[51][52][53]59]. To generate a hierarchical dendrogram, several agglomerative hierarchical clustering methods (reviewed in [56]) can cluster microbial beta diversity distances.…”

Exogenous hydrogen sulphide supplement accelerates skin wound healing via oxidative stress inhibition and vascular endothelial growth factor enhancement

“…Skin is a soft tissue accounting for about 8% of the total body mass, which covers the entire surface with self‐repair and self‐renewal ability to form an important barrier from the external environment to the internal environment . The skin acts as a barrier to prevent water loss and resist external insults . Skin trauma will destroy the barrier function of the skin, weaken normal functions and even induce skin tumors .…”

White-nose syndrome restructures bat skin microbiomes

“…Microbiomes are increasingly being recognized as critical components of host health, directly influencing a range of biochemical and physiological processes (Cho & Blaser, 2012). For mammalian skin microbiomes in particular, specific taxa are recognized as common inhabitants although these communities are just beginning to be characterized (Ross, Müller, Weese, & Neufeld, 2018). Researchers have identified several bacterial species that are associated with skin disease in humans (Findley & Grice, 2014;Zeeuwen, Kleerebezem, Timmerman, & Schalkwijk, 2013), including Staphylococcus aureus, which is linked to atopic dermatitis in children (Kong, 2011), Corynebacterium minutissimum, the agent of erythrasma, a chronic, superficial infection that causes lesions, and Streptococcus pyogenes, the most common agent of cellulitis, a diffuse inflammation of loose connective tissue (Aly, 1996).…”