E. are part of the normal flora of the skin, are responsible for body odor AND include P. acnes. Microorganisms associated with healthy tissue of host semi-permanently without causing disease are known as Normal flora or Microbial flora or Human microbiota. Most of the bacteria that reside on skin and hair are either commensalistic (beneficial to the bacteria but do not help or harm the host) or mutualistic (beneficial to both the bacteria and the host). The skin’s normal microbiota varies from one region of the body to another. It is part of the normal human flora, typically the skin flora, and less commonly the mucosal flora. The conjunctiva of the eye is a frequent site for microbial infection, but deeper eye infections are less common; multiple types of conjunctivitis exist. As the skin and outer tissues are in constant contact with the environment, microbes have easy access to colonize these areas of the body. The normal flora of humans consists of a few eucaryotic fungi and protists, but bacteria are the most numerous and obvious microbial components of the normal flora. Below the bladder, the normal microbiota of the male urogenital system is found primarily within the distal urethra and includes bacterial species that are commonly associated with the skin microbiota. All human tissue which are directly or indirectly exposed to external surrounding have normal flora. In 2007, the National Institutes of Health launched the Human Microbiome Project to survey microbial content across 242 healthy adults, develop a reference catalog of microbial genome sequences, and understand how specific habitats in the gut, genitourinary system, and skin contribute to health and disease states.14, 17, 18, 19 Recently, results … The normal microbiome on human skin. The skin’s relatively dry environment and normal microbiota discourage colonization by transient microbes. Human skin consists of two main layers, the epidermis and dermis, which are situated on top of the hypodermis, a layer of connective tissue. Our skin is populated by billions of diverse bacteria. Propionibacterium acnes is a Gram-positive bacterium that forms part of the normal flora of the skin, oral cavity, large intestine, the conjunctiva and the external ear canal. The skin is home to a wide variety of normal microbiota, consisting of commensal organisms that derive nutrition from skin cells and secretions such as sweat and sebum. The skin is home to a wide variety of normal microbiota, consisting of commensal organisms that derive nutrition from skin cells and secretions such as sweat and sebum. D. include Malassezia spp. The skin’s relatively dry environment and normal microbiota discourage colonization by transient microbes. Figure 1. Although primarily recognized for its role in acne, P. acnes is an opportunistic pathogen, causing a range of postoperative and device-related infections. The skin microbiota test uses in vitro and ex vivo models to assess the impact of compounds or formulations on the development of different bacteria on the skin. Staphylococcus epidermidis is a Gram-positive bacterium, and one of over 40 species belonging to the genus Staphylococcus. B. are responsible for body odor. In women, the normal microbiota is found within the distal one third of the urethra and the vagina. It is a facultative anaerobic bacteria. C. include P. acnes. Although S. epidermidis is not usually pathogenic, patients with compromised immune systems are at risk of developing infection. A. are part of the normal flora of the skin. The skin is an effective physical barrier against microbial invasion. Gram stain of a species of Micrococcus, commonly isolated from the skin and nasal membranes of humans. 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