Zusammenfassung der Ressource
Medical Bacteriology L1
- the skin
- first line of defense
- mechanisms to minimise microbial growth
- secretes lysozymes
- attacks and
weakens
bacterial cell
walls
- produces sebum
(fatty acid)
- Propionibacteria
metabolizes to produce
fatty acids (antimicrobial)ff
- lower pH than most
microbes can survive
- resident microbiota
- head, armpits,
groin, hands and
feet are most
heavily colonized
- microbes + skin secretions = BO
- antimicrobial deoderant
- selective against gram positive bacteria
- reduces volatile aromatic products
- can promote the colonization by gram negatve bact
- commensal microbiota
- coagulase‐negative
staphylococci
- Staphylococcus aureus
- 40% of healthy adults
- 90% of hospital staff
- surgical wound infection
- micrococci
- Micrococcus sedentarius
- pitting of toughened foot skin
- produces methanethiol
- corynebacteria
- propionibacteria
- lactobacilli
- yeasts
- genus candida
- candida albicans, though,
does not normally
colonize the skin
- also host fungi and mites
- fungi
- Malassezia furfur
- mites
- Demodex folliculorum and Demodex brevis
- eat dead epithelium supplemented by sebum
- brevibacteria
- cheesy feet; degree doesn't correlate though
- eyes have specialized skin
- bathed in tears
- resident microbiota
- Corynebacterium xerosis
- the alimentary tract
- oral cavity
- saliva
- washing
- swallow 30x/hour
- digestive enzymes & antimicrobials
- immunoglobin A (IgA)
- lysozyme
- lactoferrin
- α‐haemolytic streptococci
- Streptococcus salivarius
- eprithelial surfaces
- Streptococcus salivarius
- teeth
- Streptococcus mutans
- Streptococcus sanguis
- gingival crevices
- Bacteroides, Fusobacterium
species and spirochaetes,
forming intricate parasitic
interactions
- stomach
- low, acidic pH
- a few acid‐tolerant lactobacilli
- Helicobacter pylori
- ulcers
- highly active urease
- mycobacteria
- waxy cell wall
- small intestine
- upper:
duodenum,
jejunum, upper
ileum
- NO resident microbiota
- digestive secretions, bile acids, intestinal
mucus and secretory antitbodies
- peristalsis
- if peristalsis is
prevented, bacterial
overgrowth (intestinal blind loop)
occurs
- lower ileum
- microbiota like that
of the mouth
- large intestine
- faecal microbiota
- anaerobes dominate
- bacteriodes
- less facultative microbes
- Escherichia coli
- effects of microbiota
- microbiota's metabolism
- may produce carcinogens
- people w/o lactase
- digests oligosacccharides from beans
- creates flatulence
- controls flatulence
- utilize volatile products
- reduce our gas from 24 liters to 1 liter
- the upper respiratory tract
- microbiota of nostrils
resembles skin
- staphylococci
- micrococci
- corynebacteria
- microbes inhaled
- entrapped in the hairs
- entrapped in mucus
membranes of the
turbinate baffles
- warm, moist upper resp. tract
- gram negative bacteria
- Moraxella
- Neisseria
- Haemophilus
- gram positive bacteria
- streptococcus
- Streptococcus pyogenes
- tonsilitis
- found in
commmensal
microbiota of
healthy carriers
- not normally
colonised
- paranasal
sinuses
- larynx
- lower respiratory tract
- lungs
- mucociliary escalator
- mucus traps microbes
- cilia drive
mucus from the
alveoli, up thru
trachea
- the genital tract
- generally not v colonized
- regular flushing
- secretory antibodies
- in males: prostate secretions
- on distal portion
- staphylococci
- gram-negative cocci
- corynebacteria
- mycoplasma
- external genitalia
- Mycobacterium smegmatis
- may contaminate
urine samples and
confuse the
laboratory
diagnosis of renal
tuberculosis
- pre‐pubescent and post‐
menopausal women
- enterococci, coagulase‐negative staphylococci,
coliform bacilli and corynebacteria
- reproductive years
- lactobacilli,(Döderlein
bacilli), in a mixed
microbiota also containing
yeasts, corynebacteria and
mycoplasmas
- microbiota
- resident microbiota
- Adhere @ suitable niche on/in our body
- multiply
- form long‐term, stable,
interdependent relationships with
their neighbours and with the human
that harbours them
- transient microbiota
- 1)not find us a hospitable environment
- 2) are outcompeted by resident microbiota
- 3) are susceptable to host defenses
- role of the commensal microbiota
- coexist with host
- Staphylococcus saprophyticus
is commensal on skin
- factors that affect the human comensal microbiota
- pathogens
- Staphylococcus saprophyticus
causes harm and is pathogenic in
the urinary tract
- in the gemale genital tract, it does
not have competing microbiota
- Microbial access to deep tissues is
transient; in healthy individuals any
organisms that do enter such sites are
rapidly removed by the various host
defence mechanisms
- cerebrospinal fluid = sterile
- muscle
- joints
- bones
- connective tissue
- kidneys
- liver
- urinary tract
- spleen