Yeast: Saccharomyces "boulardii" and "cerevisiae"

[vampares]

Saccharomyces cerevisiae is a well known eukaryote. It is also sometimes referred to as "Baker's yeast" or "Brewer's yeast".

 

Saccharomyces boulardii (the best link is wikipedia) is a "natural" or "wild" yeast. It is not generally cultivated by humans.

 

The two are essentially the same to some observers.

 

Clustering of Saccharomyces boulardii strains within the species S. cerevisiae using molecular typing techniques

 

This is a preliminary genetic test of various yeast strains in which the protein codes are broken apart and sorted by size. Some are boulardii, some are not. For reference, #2 is a boulardii strain. The conclusion one might draw (I won't speak over your heads) is that cerevisiae is a broken copy of the original Eukaryote.

[jimmydasaint]

It certainly looks that way. Has this topic been controversial because one looks like a strain of the other? Additionally, are the proteins significantly different, because each yeast would display proteins on their surface, which could be recognised by antibodies?

[CharonY]

More importantly, RAPD is often not trivial to interpret and has often a low resolution. More detailed sequencing-based approaches found quite a few differences (Edwards-Ingram et al 2007, AEM) probably relevant to their different probiotic effects. However, overall similarity still suggests (afaik) that both are most likely just one species (but then species concepts in single celled organisms is often a tricky business).

Edited December 3, 2011 by CharonY

[vampares]

It certainly looks that way. Has this topic been controversial because one looks like a strain of the other? Additionally, are the proteins significantly different, because each yeast would display proteins on their surface, which could be recognised by antibodies?

 

• The proteins in the "cerevisiae" are, AFAIK, not substantially different in the sense that there was evolutionary divergence. They seem to be simply broken and are probably not expressed.
   
  Human antibodies should be able to handle the species with little or no effort at all. It is not a pathogenic species.
  Saccharomyces cerevisiae is not bred to handle nitrogen compounds. It is bred to produce carbon dioxide bubbles or alcohol (in some cases enzymes i.e. laundry detergent). This may leave potentially carcinogenic nitro compounds unreduced. Not typically an issue with white bread...
   
  The Eukaryotes, boulardii and cerevisiae, will recognize each other as a member of the same species. I read one patent application regarding boulardii, which contained research breeding boulardii with various other strains. The viability of the hybrid was between 8% and (ad hoc) ~50%.
   
   
   
  
• There is a greater issue which is of importance. This Eukaryote is not bread born, or beer born organism. It is an organism that happened to be captured by a civilization, was retained for some. Over some period of time the genome was hyjacked.
   
  Remember that many organisms can produce alcohol. The human body for instance. It is a decedent of single celled Eukaryotes. Lacto bacillus can produce both alcohol and carbon dioxide bubbles in dough.
   
  Lacto bacillus happen to have a patchy population distribution. This Eukaryote was/is prolific on a global scale.
   
   
   
  
• My observations:
   
  It has the ability to produce vitamins (most grain fortification uses brewer's yeast extracts). Many members of the animal kingdom rely upon this vitamin production. It has the ability to function in the nitrogen cycle. It functions in the sulfur cycle. It is necessary for some fungi (call this secondary fungi?) to exist. It produces glutathione.
   
  It is capable of entering the atmosphere by making use of the evaporative properties of water. Once it is there it is able to collect water into the atmosphere. A colony is able to utilize bonds amongst member to partly manipulate the atmosphere. The colony is also able to induce precipitation.
   
   
  As prolific a primal organism it is, virtually no organism would have evolved without its presence.

 

Diseases of imbalance can be substantial. One such instance may be the American Walnut. The lack of this yeast is a likely pathogenesis: via presence and persistence of another yeast-- being incapable of fulfilling the biological role -- occupying the niche.

 

It is a likely scenario for stated "algal blooms" and incurable eutrophic conditions.

 

 

Dinosaurs are extinct. I feel bad about that. I would wish it would never happen again. What is the status of evolution without this organism present in the immediate enviroment (based upon entropy not landscaping and GMO agriculture)? What is left on this ground?

Edited December 5, 2011 by vampares