Microorganisms and Virulence Figure 27.13 Further exposure at - PowerPoint PPT Presentation

Microorganisms ¡and ¡Virulence ¡

Figure 27.13 Further exposure at local sites TOXICITY: COLONIZATION toxin effects are TISSUE and local or systemic EXPOSURE INVASION ADHERENCE GROWTH DAMAGE, through epithelium to pathogens to skin or mucosa Production of DISEASE virulence factors INVASIVENESS: further growth at original and distant sites Further exposure

Table 27.3

Figure 27.5

Figure 27.16

Figure 27.1 Mucus Microbial cells Epithelial cell

Figure 27.18

Figure 27.9 Esophagus Major bacteria present Major physiological Organ processes Esophagus Prevotella Streptococcus Veillonella Secretion of acid (HCl) Helicobacter Stomach Digestion of macromolecules Proteobacteria pH 2 Bacteroidetes Actinobacteria Fusobacteria Duodenum Enterococci Continued digestion Lactobacilli Small Absorption of monosaccharides, Jejunum intestine amino acids, fatty acids, water pH 4–5 Bacteroides Bifidobacterium Ileum Clostridium Enterobacteria Enterococcus Escherichia Eubacterium Absorption of bile acids, Large Colon Klebsiella vitamin B 12 intestine Lactobacillus pH 7 Methanobrevibacter (Archaea) Peptococcus Peptostreptococcus Proteus Ruminococcus Anus Staphylococcus Streptococcus

Table 27.2

Figure 27.11 Sinuses Nasopharynx Upper respiratory Pharynx tract Oral cavity Larynx Trachea Lower Bronchi respiratory tract Lungs

Figure 27.12 Male Female Bladder Ovary Cervix Uterus Bladder Pubis Urethra Pubis Rectum Urethra Penis Prostate Vagina Rectum Testis

Figure 27.14 Highly virulent Moderately virulent organism organism ( Streptococcus ( Salmonella enterica 100 pneumoniae ) serovar Typhimurium) Percentage of mice killed 80 60 40 20 10 1 10 2 10 3 10 4 10 5 10 6 10 7 Number of cells injected per mouse

Table 27.6

Table 27.4

Figure 27.19

Table 27.5

Figure 27.22 Excitation signals from the central nervous system Muscle Normal Botulism Acetylcholine (A) induces Botulinum toxin, , blocks contraction of muscle fibers release of A, inhibiting contraction

Figure 27.23 Inhibitory interneuron Inhibition Tetanus toxin Excitation signals from the central nervous system Muscle Normal Tetanus Glycine (G) release from inhibitory Tetanus toxin binds to inhibitory interneurons stops acetylcholine interneurons, preventing release (A) release and allows relaxation of glycine (G) and relaxation of muscle of muscle

Figure 27.24 Normal ion movement, Na + from lumen to blood, no net Cl - movement Blood Intestinal Lumen of small intestine epithelial cells GM1 Colonization and toxin production by V. cholerae Cholera toxin AB form GM1 Vibrio cholerae cell Activation of epithelial adenylate cyclase by cholera toxin A subunits Cholera toxin B subunit Adenylate cyclase ATP Cyclic AMP Na + movement blocked, net Cl - movement to lumen Massive water movement to the lumen; cholera symptoms

Microbial Sidebar 27.2b Enterotoxin Injectosome (diarrhea) ( inv and prg Siderophores products form Type I fimbriae complex) (adherence) Endotoxin in LPS layer (fever) Virulence plasmid Anti-phagocytic Cytotoxin proteins (inhibits host cell protein induced synthesis; calcium efflux by oxyR from host cell; adherence) Vi capsule antigen; O antigen inhibits complement binding (inhibits phagocyte killing) Flagellum (motility) H antigen (adherence; inhibits phagocyte killing)

Figure 27.10