GRAM4 - inhabitants are killed off by antibiotics b...

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GRAM-POSITIVE BACTERIA These are divided into two groups---those that have a high G + C ratio and those with a low G +  C ratio. (To determine this, the DNA of the organisms is studied. The percentage of cytosine and  guanine is compared to the percentage of adenine and thymine and that is the G + C ratio.) A. LOW G + C GRAM-POSITIVE BACTERIA----the Firmicutes 1. CLOSTRIDIALES a. Genus  Clostridium —these are obligate anaerobes that form endospores, which are highly  resistant to heat, drying, and chemicals.  1)  C. tetani— causative agent of tetanus 2)  C. botulinum —causes botulism, a severe form of food poisoning that can be fatal 3)  C. perfringens —gas gangrene in wounds and also gastrointestinal upsets 4)  C. difficile —can cause very serious diarrhea (pseudomembranous colitis) when other 
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Unformatted text preview: inhabitants are killed off by antibiotics. b. Epulopiscium—E. fishelsoni is newly discovered and really strange. Its size is tremendous compared to other bacteria—80 X 600 μ m when normal bacteria might be 1 X 2 μ m. It was found living in symbiosis in the gut of Red Sea surgeon fish, and at first thought to be a protozoan. However, it has no nucleus and bacterial flagella, so a new genus was created for it and it is now classified as a bacterium. Its reproduction is atypical also—daughter cells form inside and are released through a slit opening. 2. BACILLALES—gram-positive rods and cocci. a. Bacillus —these are rods that produce endospores. Most are nonpathogenic but there are exceptions:...
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This note was uploaded on 01/23/2012 for the course MCB MCB2010 taught by Professor Smith during the Fall '09 term at Broward College.

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