Lecture 21 Skin And Respiratory Microbiomes PDF

FQ2024 MIC111 L21: Skin and respiratory microbiomes  21 Learning Goals Understand diversity, drivers of diversity, and functions of the skin microbiome Understand how skin microbiome changes during development Describe some examples of how interactions of the skin microbiome commensals can...

FQ2024 MIC111 L21: Skin and respiratory microbiomes  21 Learning Goals Understand diversity, drivers of diversity, and functions of the skin microbiome Understand how skin microbiome changes during development Describe some examples of how interactions of the skin microbiome commensals can limit or sometimes promote growth of pathogens Define functions and impacts of skin microbiome fungi on health an disease Describe how skin, oral, gut, lung microbiomes can be linked Define roles of commensal microbes in lung health and disease  coating that lubricates and provides an antibacterial shield to hair and skin. Depending on the method used to sample the skin microbiota (swab, biopsy, surface Abiotic features and cellular structure of the skin scrape, cup scrub or tape strip), microorganisms residing at different depths or subcompartments of the skin are captured92,115–117. Although most major bacterial taxa are similarly identified regardless of sampling method92, some microorganisms are variably present at the surface compared with deeper skin layers118–120; this emphasizes the Two distinct layers - blood and nerve importance of maintaining consistent sampling techniques throughout a study. In general, the studies highlighted throughout this Review utilize methods that capture supply microorganisms on and within the stratum corneum; additional studies with more invasive sampling techniques are necessary to fully understand the spatial distribution epidermis - keratinocytes - linked of microorganisms in the skin. to form resistant keratin barrier Bacteria: Fungi: dermis - sebum - seal for hair Propionibacterium spp. Malassezia spp. Staphylococcus spp. folicles Corynebacterium spp. Virus high turnover microenvironments have variation in Epidermis oxygen, UV light, pH, temperature, moisture, sebum content moisture/oily variation sebaceous /oily = face, chest, back Dermis Sebaceous gland Hair follicle moist = bend of elbow, knee, groin Sweat gland dry = palm, forearm sweat glands = thermoregulation, but also acidifies the skin (anti- Nature Reviews | Microbiology 144 | MARCH 2018 | VOLUME 16 microbial) © 2018 Macmillan Publishers Limited, part of Springer Nat sweat also has free fatty acids and  coating that lubricates and provides an antibacterial shield to hair and skin. Depending on the method used to sample the skin microbiota (swab, biopsy, surface scrape, cup scrub or tape strip), microorganisms residing at different depths or General functions of the skin microbiome subcompartments of the skin are captured92,115–117. Although most major bacterial taxa are similarly identified regardless of sampling method92, some microorganisms are variably present at the surface compared with deeper skin layers118–120; this emphasizes the importance of maintaining consistent sampling techniques throughout a study. In general, the studies highlighted throughout this Review utilize methods that capture skin microbiome train immune microorganisms on and within the stratum corneum; additional studies with more invasive sampling techniques are necessary to fully understand the spatial distribution system of microorganisms in the skin. dysbioses associated with a Bacteria: Fungi: variety of skin disorders Propionibacterium spp. Staphylococcus spp. Malassezia spp. fermentative metabolism Corynebacterium spp. Virus produces SFCA - proprionate butyrate Epidermis end products important for keratinocyte barrier integrity also produce vitamins K and B12 UV exposure influences vitamin D Sebaceous production but Dermis gland Hair follicle diet can influence skin microbiome Sweat gland enhances wound healing through interaction with innate immune Nature Reviews | Microbiology system..but downside is biofilms 144 | MARCH 2018 | VOLUME 16 or MRSA associated with wounds © 2018 Macmillan Publishers Limited, part of Springer Nat Proprionibacterium acnes Staphlococcus epidermus Corynebacterium Malassezia (yeast - fungi)  ther promote colonization, various Staphylococcus spp. Initial colonization and population shifts. In newborn can also produce adherens that promote attachment to babies, initial colonization of the skin is dependent on the skin and proteases that liberate nutrients from the delivery mode; neonates born vaginally acquire bac- stratum corneum1. Overall, the skin harbours a hetero- teria that colonize the vagina, whereas neonates born geneous community of microorganisms that each have via Caesarian section acquire microorganisms that are Skin microbiome species variation by moisture/sebum distinct adaptations to survive on the skin. associated with the skin39,40. The long-term effects of Table 1 | Top ten abundant bacterial, eukaryotic and viral species that are present by physiological grouping of sites Dry* Moist‡ Sebaceous§ Foot|| Bacteria Propionibacterium acnes Corynebacterium tuberculostearicum Propionibacterium acnes Corynebacterium tuberculostearicum Corynebacterium tuberculostearicum Staphylococcus hominis Staphylococcus epidermidis Staphylococcus hominis Streptococcus mitis Propionibacterium acnes Corynebacterium tuberculostearicum Staphylococcus warneri Streptococcus oralis Staphylococcus epidermidis Staphylococcus capitis Staphylococcus epidermidis Streptococcus pseudopneumoniae Staphylococcus capitis Corynebacterium simulans Staphylococcus capitis Streptococcus sanguinis Corynebacterium fastidiosum Streptococcus mitis Staphylococcus haemolyticus Micrococcus luteus Corynebacterium afermentans Staphylococcus hominis Micrococcus luteus Staphylococcus epidermidis Micrococcus luteus Corynebacterium aurimucosum Corynebacterium afermentans Staphylococcus capitis Enhydrobacter aerosaccus Corynebacterium kroppenstedtii Corynebacterium simulans Veillonella parvula Corynebacterium simulans Corynebacterium amycolatum Corynebacterium resistens Eukarya Malassezia restricta Malassezia globosa Malassezia restricta Malassezia restricta Malassezia globosa Malassezia restricta Malassezia globosa Trichophyton rubrum Proprionibacterium Aspergillus tubingensis Tilletia walkeri Malassezia sympodialis Malassezia globosa Candida parapsilosis Zymoseptoria tritici Staphylococcus Malassezia sympodialis Pyramimonas parkeae Aureoumbra lagunensis Tilletia walkeri Pyramimonas parkeae Trichophyton mentagrophytes Malassezia sympodialisStreptococcus Parachlorella kessleri Pycnococcus provasolii Parachlorella kessleri Corynebacterium Epidermophyton floccosum Pyramimonas parkeae Aspergillus tubingensis Zymoseptoria tritici Gracilaria tenuistipitata Pyramimonas parkeae Aspergillus tubingensis Zymoseptoria tritici Nannizzia nana Nephroselmis olivacea Parachlorella kessleri Gracilaria tenuistipitata Other functions and variations in the skin microbiome Skin is front line barrier to outer environment - cuts or wounds disrupt balance Staphylococcus epidermidis – the “accidental” pathogen Staphylococcus epidermidis gram+ cocci bacteria that form clusters facultative anaerobe. In natural environments such as the human skin or mucosa, they are usually harmless. can invade wounds- common cause of hospital infections - like Staph aureus produce biofilms - as method to attach to surfaces. biofilms protect against host defenses, antibiotics, etc.  Host skin microbiome can limit pathogen S. aureus colonization MRSA - methicillin-resistant S. S. aureus = causes serious aureus - serious concern in skin infections, and can become hospitals systemic through wound Skin microbiome has both positive invasion and negative interactions that impact S. aureus colonization and biofilm formation. Propionibacterium acnes Small molecule: coproporphyrin III Antibiotic: S. lugunensis and S. hominus lugdunin Staphylococcus Staphylococcus produce lantibiotics agains S. aureus lugdunensis Bio lm aureus Lantibiotic Serine Staphylococcus S. epidermis secretes proteases protease: Esp hominis that inhibit S. aureus biofilms Antimicrobial Staphylococcus peptides In contrast, P. acnes produces epidermis copropophyrin that promotes Epidermis S.aureus aggregations S. epidermis colonization and genetic exchange with S. aureus Staphylococcus epidermidis = dominant colonizer of moist skin sites. also colonizes skin niches at different densities including: epidermis and interior of the hair follicle High strain-level variation skin-colonizing S. epidermidis including virulence factors and antibiotic resistance factors (ABRs), plasmids, phages a Can exchange antibiotic resistance genes or enterotoxins, and metal resistance genes between related S. aureus species. MRSA= methicillin-resistant S. aureus MRSE = methicillin-resistant S. epidermidis. C. acnes: microbial competition at the hair follicle cutimycin = AMP Cutibacterium acnes = dominant hair follicle colonizer Overgrowth of C. acnes is correlated with progression of the common skin disease “acne vulgaris”. C. acnes competes with follicle-resident S. epidermidis through production of the antimicrobial peptide (AMP) cutimycin. C. acnes inhibits S. epidermidis biofilm formation and sensitizes S. epidermidis to antibiotic killing through production of SCFAs S. epidermidis suppresses C. acne overgrowth by production of AMPs and fermentation of follicle-available glycerol to multiple short-chain fatty acids, including acetic acid, butyric acid, lactic acid and succinic acid Common fungi in the skin microbiome can be opportunistic pathogens Malassezia fungi found on the human and animal skin microbiomes Malassezia spp. are Basidiomycetous fungi (related to mushrooms) requires lipids to grow — common in areas with many sebaceous glands: on the scalp face, and upper part of the body. M. globosa uses different types of lipases and phospholipases to break down the oils on the scalp. When the fungus grows too rapidly, the natural renewal of cells is disturbed, causes dandruff, eczema, dermatitis In immunocompromised hosts, Malassezia can also cause systemic infections. Nasal and lung microbiome ARI = acute respiratory illness; LRI = lower repiratory illnes Drivers of lung microbiome dysbioses or disease relationship between oral/nasal cavity, and lung microbiomes -> dysbioses Drivers of lung microbiome dysbioses or disease Scales of microbe-host interactions