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6_Prokaryote_Meet_the_Microbes

Not accessible to the action of antibiotics outer

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Not accessible to the action of antibiotics. Outer membrane is similar to the plasma membrane, but is less permeable and contains lipopolysaccharides (LPS). LPS is a harmful substance classified as an endotoxin. From the Virtual Microbiology Classroom on ScienceProfOnline.com
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Bacterial Genus : ______________ GRAM-POSITIVE Obligate anaerobes bacillus-shaped The members of this genus have a couple of bacterial “superpowers” that make them particularly tough pathogens. Q: Anyone remember what those superpowers are? All have a strictly fermentative mode of metabolism (Don’t’ use oxygen). Vegetative cells are obligate anaerobes killed by exposure to O2, but their endospores are able to survive long periods of exposure to air. Known to produce a variety of toxins, some of which are fatal. - Clostridium tetani = agent of tetanus - C. botulinum = agent of botulism - C. perfringens = one of the agents of gas gangrene - C. difficile = part of natural intestinal flora, but resistant strains can proliferate and cause pseudomembranous colitis. Images: Man with Tetanus , Sir Charles Bell; Clostridium botulinum, PHIL #2107; Wet Gangrene , Wiki From the Virtual Microbiology Classroom on ScienceProfOnline.com
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GRAM-POSITIVE Obligate or facultative anaerobes bacillus-shaped Common in soil. Only a few species cause disease in humans. Extremely diverse group of bacteria, includes: - causative agent of anthrax ( Bacillus anthracis ) - species that synthesize important antibiotics, and enzymes for detergents. Produce ___________. Due to extreme tolerance to both heat and disinfectants, used to test heat sterilization techniques and chemical disinfectants. Bacterial Genus : __________ Images: Bacullus subtilis , T. Port: B. anthracis , Gram stained , CDC; Endospore stain , Tami Port This is our lab friend Bacillus subtilis . Gram Stain Endospore Stain From the Virtual Microbiology Classroom on ScienceProfOnline.com
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Organism: Caused by the Gram + , endospore- forming bacterium ______ ______. Infection can occur in three forms: - cutaneous (skin) - inhalation - gastrointestinal Transmission: Endospores can remain in soil for many years. Humans can become infected by handling products from infected animals or by inhaling spores. Cutaneous Anthrax Infection: •M o s t (about 95%) anthrax infections occur when the bacterium enters a cut or abrasion on the skin. Skin infection begins as a raised itchy bump that resembles an insect bite. Within 1-2 days develops into painless ulcer, with a characteristic black necrotic (dying) area in the center. About 20% of untreated cases result in death. ( Death rare with appropriate antimicrobial therapy). Disease, Please : Anthrax Bacillus anthracis Gram Stain Images: B. anthracis , Gram stained, CDC; Anthrax skin lesion , James H. Steele, CDC From the Virtual Microbiology Classroom on ScienceProfOnline.com
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GRAM-POSITIVE Facultative anaerobe, cocci Thick cell wall , ~50% of cell’s mass.
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Not accessible to the action of antibiotics Outer membrane...

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