Epidermidibacterium keratini gen. nov., sp. nov., a member of the family Sporichthyaceae, isolated from keratin epidermis

Abstract

A novel actinobacterial strain, designated EPI-7, was isolated on R2A agar from human skin (keratinocytes) and subjected to a taxonomic study using a polyphasic approach. Strain EPI-7 showed a Gram-positive reaction, was non-motile, non-spore-forming, and cells had a rod-shape. Colonies were round, convex and pale yellow. Phylogenetic analysis based on 16S rRNA gene sequences showed that the novel isolate formed a cluster with several uncultured bacterial clones and with cultured members of the genera Modestobacter and Sporichthya. The 16S rRNA gene sequence similarities with respect to the type strains of recognized species from the above genera and other phylogenetic neighbours ranged from 92.6 to 93.4 %. The G+C content of the genomic DNA was 68.9 mol%. The only isoprenoid quinone was MK-9(H4), and the major fatty acids detected were C17 : 1ω8c, C16 : 0, iso-C15 : 0 and summed feature 3. The major polar lipids were found to be phosphatidylethanolamine, phosphatidylinositol, three unidentified phospholipids, phosphatidylglycerol, phosphatidylcholine, two unidentified amino lipids and three unidentified lipids. The cell-wall peptidoglycan contained meso-diaminopimelic acid, glutamic acid and alanine. Whole-cell sugars present included rhamnose, glucose and galactose. The combination of the genotypic and phenotypic data allowed differentiation of strain EPI-7 from its closest phylogenetic neighbours and provided evidence that strain EPI-7 represents a novel genus and species in the family Sporichthyaceae. The name Epidermidibacterium keratini gen. nov., sp. nov. is proposed with the type strain being EPI-7 (=KCCM 90264=JCM 31644).

Efficacy and Safety of Epidermidibacterium Keratini EPI-7 Derived Postbiotics in Skin Aging: A Prospective Clinical Study

“…Epidermidibacterium Keratini (EPI-7) is a novel actinobacteria isolated from the skin microbiomes of two different age groups of females, which was found to be more prevalent in the 20s age group [22,23]. EPI-7 ferment filtrate has previously shown its anti-aging property by modulating activities of matrix metalloproteinases (MMPs) in UV-induced photo-aging in human dermal fibroblasts [23].…”

Genome-Wide Pathway Exploration of the Epidermidibacterium keratini EPI-7T

“…The Epidermidibacterium keratini EPI-7 T was first introduced by Lee DG et al in 2018. In a previous study, a novel bacterial strain, EPI-7 T , was isolated from skin samples (human epidermal keratinocytes) and characterized by taxonomic identification [1]. In addition, it has been proven that E. keratini EPI-7 T culture solutions have a positive effect on the improvement of anti-aging-related gene expression in Hs68 cells to UV-irradiated fibroblast cells [2].…”

A 1,1′-biuracil from Epidermidibacterium keratini EPI-7 shows anti-aging effects on human dermal fibroblasts

“…One group was in their 20 s, and the other was in their 40 s. Analysis of 16S rRNA gene sequences showed a newly found bacterium that shares 93.4% homology with the genus Sporichthya, indicating the discovery of a novel genus. We isolated a novel bacterial stain, Epidermidibacterium keratini, called EPI-7 T [2], from skin samples. Additionally, the younger skin appeared to have high proportion of EPI-7 T , while the older skin had no EPI-7 T but rather other types of bacteria.…”