Microbiology Ch. 30 (final exam)
Terms
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- the discipline that uses microorganisms, usually grown on a large scale, to produce valuable commercial products or carry out important chemical transformations
- industrial microbiology
- term used to describe the reactions carried out by microorganisms in industrial microbiology
- biocatalysis
- the major organisms used in biocatalytic processes are:
- fungi (yeasts and molds) and certain prokaryotes, in particular members of the genus Streptomyces.
- examples of industrial products of cells are:
- yeast for food, baking, and brewing
- examples of industrial products from the products of cells are:
- enzymes (glucose isomerase), antibiotics (penicillin), food additives (aspartame, amino acids), alcohol (ethanol), and chemicals (citric acid)
- the properties of an effective industrial microorganism are:
- the ability to produce product of interest in high yield, grow rapidly on inexpensive culture media available in bulk quantities, nonpathogenic, and be amenable to genetic manipulation.
- the use of microorganisms to carry out a specific chemical transformation
- biocatalysis
- type of microbial metabolite (byproduct of metabolism) formed during the growth phase of the microorganism
- primary metabolite
- type of microbial metabolite (byproduct of metabolism) formed near the end of the growth phase of the microorganism frequently at, near, or in the stationary phase
- secondary metabolite
- why is dramatic overproduction as well as complete repression of secondary metabolites common?
- because it is not directly linked to growth and metabolism like primary metabolites
- the product resulting from the conversion of ethyl alcohol to acetic acid by acetic acid bacteria
- vinegar
- acetic acid bacteria include members of the genera
- acetobacter and gluconobacter
- vinegar can be produced from any substance that contains ethanol; the usual starting material is:
-
wine, beer, or alcoholic apple juice (cider)
can also be produced from mixture of pure alcohol in water, known as distilled vinegar. - acetic acid bacteria are strict aerobes/anaerobes?
- strict aerobes
- how do acetic acid bacteria such as gluconobacter differ from other strict aerobes?
- do not oxidize their organic electron donors completely to CO2 and water.
- the main problem in the production of vinegar is to ensure:
- sufficient aeration of the medium
- acetic acid bacteria are _____, and can survive in the byproducts of their metabolic processes
- very acid tolerant
- vinegar production method where wine is placed in shallow vats with considerable exposure to the air, and the acetic acid bacteria develop as a slimy layer on the top of the liquid; this was the original process, and is inefficient
- open-vat/orleans method
- vinegar production method where alcoholic liquid is trickled over beechwood twigs or wood shavings packed loosely in a vat or column while a stream of air enters at the bottom and passes upward. the bacteria grow on the surface of the wood shavings.
-
trickle method
vat is known as a vinegar generator - vinegar production method with a submerged fermentation process. efficiency is extremely high - up to 90%-98% of alcohol is converted to acid.
- bubble method
- most fruit juices undergo natural fermentation caused by:
- wild yeasts that are present on the fruit
- alcoholic beverage produced by the fermentation of fruit juice
- wine
- alcoholic beverage produced by the fermentation of malted grains
- beer or ale
- alcoholic beverage produced by concentrating alcohol from a fermentation or distillation
- distilled beverages
- chemicals responsible for the color and stronger flavor of red wines
- tannins
- species of cultivated wine yeast
- saccharomyces ellipsoideus
- sulfur dioxide (sulfites) is added to the wine in order to kill the natural yeasts because:
- the wild yeasts are less alcohol tolerant and can produce undesirable compounds affecting quality and taste of the final product.
- the majority of ethanol in the U.S. is produced by
- saccharomyces