The arginine deaminase system plays distinct roles in Borrelia burgdorferi and Borrelia hermsii

Abstract: https://pubmed.ncbi.nlm.nih.gov/35286343/

Full text: https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1010370

I thought these parts were interesting:

"Additionally, B. burgdorferi growth was inhibited in the presence of increasing levels of L-arginine, an effect that was not observed in B. hermsii growth experiments (Fig 3A and 3B). The addition of L-ornithine to B. burgdorferi cultures at 1/20 the equimolar concentration of L-arginine ameliorated the L-arginine-stimulated growth defect, suggesting that B. burgdorferi is exquisitely sensitive to the levels of L-arginine and L-ornithine in its environment. This was unique to B. burgdorferi and is likely due to differences in the action of the antiporter, ArcD, which canonically exchanges L-arginine (in) for L-ornithine (out) in response to the intracellular and extracellular concentrations of those metabolites [50]. Further work will be required to determine the factors that contribute to the tight ADI regulation observed in B. burgdorferi uncovered in this study."

[...]

"Because in vitro experiments showed that B. burgdorferi did not utilize L-arginine directly, it was not surprising that wild-type infected mice did not have reduced plasma levels of L-arginine. However, the observed increase in plasma L-ornithine was unexpected. In mammals, the enzyme arginase II generates L-ornithine and is the first step in polyamine production by phagocytic cells (alternative activation pathway in macrophages) [72]. In a murine Lyme arthritis and carditis model, Lasky et al. showed that alternatively activated macrophages expressing arginase II outnumbered classically activated macrophages 100-fold throughout their six-week infection experiment [61). In our study, L-ornithine was readily available in mouse plasma and levels significantly increased during a wild-type B. burgdorferi infection. In general, macrophage polarization can dramatically affect infection outcomes and the expression of host arginases to produce polyamines is considered an anti-inflammatory signal. "

Hi Garzie,

Thank you!!

Yes for the most part it isn't really an actionable study.

However, what I did get from it is that L-arginine might inhibit the growth of B. Burgdorferi but that this didn't happen in B. hermsii.

So in that sense, if people wonder why L-arginine didn't work for them or didn't make them herx, it might help to understand different Lyme strains react different to L-arginine.

That's what I got from it anyway haha.

Hey Garzie,

Thank you again! No need to apologize, I actually noticed the same thing - a few years ago there were lots of studies about what might treat these infections abx/herbs/combos/dsf etc. And recently it has all kind of disappeared in favor of these kind of studies. It's very discouraging to me.

Thank you for the information you provided, that's really interesting. I wonder if there's a difference between how young people with more arginine react to borrellia vs older people with less arginine.

Do you notice benefit from the 4-5 grams a day?

Hope you're doing well!

Oh that's great Garzie!

I take L-Citrulline sometimes, it's like a byproduct downstream nitric oxide/arginine production.

I definitely understand not wanting to take something out when you've made so much progress.