Please allow me to answer your question about yeast, bread and beer. I have been brewing beer, wines and meade for about 10 years now.
Short answer, yes you can use the bread yeast for beer and vice versa, but with unpredictable results from the beer. Long answer follows...
I have taken small cultures of yeast from the bottom of imported beer bottles and cultured it. It is not hard. It is a simple microorganism that wants simple carbohydrates (mostly sugars). Yeast produces alcohol and carbon dioxide as a byproduct of metabolizing the sugars ( along with various esters and other compounds that give signature flavors). It likes to be warm, between 60 and 80 Fahrenheit. Under 60 slows the process and over 80 starts producing methyl alcohol which you DONT want.
The yeast used to make bread is the same genus and species used to make beer and wine, however, the various strains give different flavors and alcohol percentages. These strains will drift (minor mutations) over time so you cannot keep using the yeast over and over if you want the same result from your beer. The commercial beer and wine yeast strains are produced in a lab and carefully monitored for mutations that create off flavors. Yeast for bread does not have the same stringent requirements for quality control. Any brewers yeast will work fine for bread. Beers made with baking yeast tend to be chaotic with weird flavors. Bakers yeast is fine for fruit juice hooch since that often has off flavors anyways.
Feel free to use baker's yeast to make beer or alcohol if you wish, it can yeild interesting results ( banana and clove flavors, anyone?)
