Human odors depend on many extrinsic (such as food or clothing) and intrinsic factors - localized or systemic.
In recent years, microbes responsible for localized malodors - bad breath caused by oral bacteria and axillary odor - have been mapped using next generation sequencing approaches. However, Intestinal microbes responsible for systemic malodor (whole-body and extraoral halitosis), remain to be identified.
Our preliminary analysis of culture-, PCR- and 16S-RNA-based data donated by MEBO and PATM community members show that there are no easy answers.
In recent years, microbes responsible for localized malodors - bad breath caused by oral bacteria and axillary odor - have been mapped using next generation sequencing approaches. However, Intestinal microbes responsible for systemic malodor (whole-body and extraoral halitosis), remain to be identified.
Our preliminary analysis of culture-, PCR- and 16S-RNA-based data donated by MEBO and PATM community members show that there are no easy answers.
"Lower Firmicutes to get firm and cute," says a news headline. MEBO population is low in Firmicutes and higher in Bacteroidetes. In fact, the very low F/B ratio is just about the only thing in common across the population in the Genova PCR-based microbiome analyses. The figure above shows typical representatives of MEBO "sweet" (on the left) and "non-sweet" (on the right) groups, as defined in our previous posts, video presentations and reports.
uBiome data, including SmartGut and Explorer, shows that MEBO community doesn't really have too many smellier bacteria, and likely has lower trimethylamine-producing potential than the average population. Many odoriferous bacteria - such as Odoribacter (ammonia odor), B. crossotus (rancid butter) and Desulfovibrio piger (rotten eggs) are often low in numbers, in at least one of the tests for every participant. But the composition of "scent tones" differs from normal.
This phylogenetic tree shows some of the bacteria found in abnormal levels in the MEBO community (underlined). Other bacteria displayed were found to cause (red) or compensate for (green) halitosis and underarm odors. TMA- and/or sulfide-producers are shown in brown. Some of them - like Staphylococcus hominis - produce additional volatiles like thioalcohols responsible for the characteristic unpleasant body odor smell. As seen from the figure, many bacteria can be either good or bad smell-wise on species level. This means that our 16S-RNA-based data doesn't always have sufficient resolution and might not adequately uncover the odor-producing potential.
Our preliminary findings show that "sweet" group of MEBO community is high in Anaerotruncus colihominis - indole (fecal smell) producing bacteria that utilises sugars glucose and mannose. Everyone seems to be low in Ruminococcus albus - a primary cellulose degrader that produces hydrogen and sweet-smelling acetate. 60% are low in Oxalobacter formigenes. Many participants had higher levels of Proteobacteria - but everyone had their own species - such as E.coli, Citrobacter freundii, Enterobacter Cloacae, Klebsiella or Aggregatibacter. Butyric acid-producing Butyrivibrio crossotus was abnormal in all of our samples: either too high or (mostly) too low. We also observed cases when the gut microbiota was significantly unstable - similar to Crohn's disease (even when patients are in remission).
We owe much of our general good health to the results of bacterial wars when the "good" species are destroying the "bad" invaders. Could it be that systemic malodor arises from bacterial wars that have no real purpose? Our research is only just beginning.
Our preliminary findings show that "sweet" group of MEBO community is high in Anaerotruncus colihominis - indole (fecal smell) producing bacteria that utilises sugars glucose and mannose. Everyone seems to be low in Ruminococcus albus - a primary cellulose degrader that produces hydrogen and sweet-smelling acetate. 60% are low in Oxalobacter formigenes. Many participants had higher levels of Proteobacteria - but everyone had their own species - such as E.coli, Citrobacter freundii, Enterobacter Cloacae, Klebsiella or Aggregatibacter. Butyric acid-producing Butyrivibrio crossotus was abnormal in all of our samples: either too high or (mostly) too low. We also observed cases when the gut microbiota was significantly unstable - similar to Crohn's disease (even when patients are in remission).
We owe much of our general good health to the results of bacterial wars when the "good" species are destroying the "bad" invaders. Could it be that systemic malodor arises from bacterial wars that have no real purpose? Our research is only just beginning.
RSS Feed
