That's Flagylⁱ's usual mechanism of action, but doesn't explain its effectiveness against Cpnⁱ, since Cpn isn't an anaerobe.

Oh, the bacteriostatics in the CAPⁱ work quite well against most anaerobic bacteria. It's Cpnⁱ in particular that resists those bacteriostatics, by going into the cryptic state, where it largely is shut down. (On the molecular level, many of the bacteriostatics operate like a monkey wrench thrown into some machinery; if the machinery is running, it sucks up the wrench and grinds itself into pieces, but if it is idle, the wrench just bounces off.) That lack of activity is mostly what defines the cryptic state (aka "persistent state"): the germ isn't doing much, although there is some activity and even a little growth. But being active is a different question from being aerobic; there are anaerobic bacteria which are very active (such as gut bacteria), and there are also aerobic bacteria which go into a persistent state in which they are unaffected by antibioticsⁱ. Aerobic means using oxygen; and each Cpn cell is surrounded by a human cell which has an oxygen supply. Oxygen diffuses across membranes very readily, so that gives the Cpn cell an oxygen supply, too. It thus never has to work anerobically. It might choose to, for reasons of its own, but never has to. Most of Cpn's energy comes from stealing ATP, which is probably best regarded as being neither aerobic nor anaerobic, since ATP is the end product of both aerobic and anerobic metabolism.

Now, Cpn contains some of the chemistry that anaerobic cells have. In particular, it has a gene for ferredoxin, which is used in anaerobic respiration. Ferredoxin is the molecule that passes an electron to metronidazole, activating it and turning it into a free radical that goes around chewing on DNA and other vital molecules. But that doesn't mean Cpn is ever an anaerobe: it doesn't necessarily use that ferredoxin for anaerobic metabolism, but rather might be using it for something else. (It isn't even necessarily making that ferredoxin in the first place; having a gene for something doesn't mean it's expressed.) And activation by ferredoxin isn't necessarily how metronidazole works against Cpn; that's just something that has been suggested as a possibility, not something that has been tested in detail.

Yes, Norman

That may be the closest thing to "layman's terms"

ever!   For us non-chemists, it is a huge help.

Rica

 

Uh, what's the difference? If you're on a CAPⁱ, there are antibioticsⁱ in your system 24 hours a day.

Homina, our protocol is pretty much this: 200mg doxycycline DAILY, 250mg azithromycin on each Monday, Wednesday and Friday, PLUS, for five days out of each twenty-eight days, we ADD 1200-1500mg a day of metronidazole or tinidazole.

You are doing something completely different. No, we do NOT take a 'day off' or a 'week off' other antibioticsⁱ when we pulse the nidazole.

Homina, I did not say you are doing something completely outrageous. I said you are doing something completely different from the protocol most of us here use.  

Of course you are free to take whatever meds you choose, whenever you choose to use them, however often you choose.  Newbies, however, who have no background in this,  should be periodically reminded when a member is posting about using a protocol not normally advised here.

My response was directly related to the comment you posted, "When I pulse with Flagylⁱi one day a week I do not use any other antibiotic that day I am getting results but wonder if I could get better results"

Perhaps you would get those 'better results', if you were using the actual protocol devised by the physicians  at Vanderbilt and refined by Dr. Wheldon, which is the one I referred to, and is commonly used by the members here. 

Taking sporadic abxⁱ, on and off, on and off,  is one of the methods used in medical trials to DELIBERATELY create resistance.   If this is how you and your doctor choose to treat your infection, then you should probably be consulting your doctor as to "When I pulse with Flagyli one day a week I do not use any other antibiotic that day I am getting results but wonder if I could get better results" .

Going off the other antibioticsⁱ for a day, you'll still have some in your system; the azithromycin, in particular, has a 3-day half-life. But generally it doesn't help to go off the bacteriostatic antibiotics; if you need a break, postpone the Flagylⁱ instead.

As for why Flagyl should be taken with other antibiotics, one reason that has been offered is that Cpnⁱ needs to be in the cryptic state, for Flagyl to affect it; and the other antibiotics put it into the cryptic state. Another is that bacteria have repair proteins, which could fix the DNA damage that Flagyl does to them, and the other antibiotics suppress that repair by inhibiting protein synthesis. But these mechanisms are tentative; the experiments haven't been done to nail them down precisely. Still, that something changes dramatically when Flagyl is combined with the other antibiotics is clear, and not just from the Vanderbilt experiments: doctors in general have a lot of experience with Flagyl, mostly taken on its own; and they don't regard it as producing the sort of reactions we expect from it when taken with other antibiotics -- neither the initial distress, nor the long-term improvement.