bactitech
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I assume you mean Clostridium perfringens? If so, I don't know. :-)
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Clinical Microbiology since 1974
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| mjl1717
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perhaps chromosomal mediated antibiotic resistance.
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| adeelmd
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how does it's exotoxin work???
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| Microteacher
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The main toxin of Clostridium perfringens is the alpha toxin. It's a lecthiniase or a phospholipase if you prefer the more general term. It works by destablising the host cell membrane by knocking off the polar head group from the phospholipids. This causes a pretty indiscriminate lysis of most mammalian cells - hence the extensive tissue damage that we see with Clostridial infections such as gas gangrene. :shock:
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| bactitech
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One way of identifying C. perfringens (an older way) is to use a Lactose/Lecithinase plate (known as LL agar). If you streak the suspected colony for isolation onto this plate and incubate anaerobically, C. perfringens will grow as a yellow colony with a precipitate (the lecithinase) growing as a halo around the colony.
In our lab, we use an Anaerobic ID system that takes four hours, once the needed aerotolerance subcultures are performed. Anaerobic cultures take awhile to perform, as any colonies that grow must be proven to be anaerobes before identification takes place. We let the original anaerobic plates incubate for two days before looking at them, as anaerobes (other than C. perfringens) are slow growing. Any suspected colonies are subcultured aerobically and anaerobically overnight (now into day 3). Then, if there is no growth aerobically, and lots of growth anaerobically we set up a 4 hour ID system. We see this organism fairly often, usually from abdominal sources or from sites like stump wounds from diabetics. We have a cooked meat broth culture set up for all our anaerobes, and C. perf. has LOTS of gas, and will force the meat halfway up the tube. I have seen blood culture bottles positive for C. perf. that have so much gas that the rubber septum is bulged. If you put a syringe into the bottle to subculture it, and leave the syringe in, it will blow the plunger right out of the syringe hub! This organism was responsible for many amputations during the US Civil War in the 1860's, as there was no concept of bacteria causing disease or antisepsis taking place on battlefields at that time. I'm sure C. perfringens has been responsible for many war wounds and deaths throughout the ages.
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Clinical Microbiology since 1974
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