Saccharomyces cerevisiae: Difference between revisions
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Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence? | Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence? | ||
Does it have any plasmids? Are they important to the organism's lifestyle? | Does it have any plasmids? Are they important to the organism's lifestyle? | ||
A most conspicious feature of the yeast genome, | |||
compared with that of multicellular organisms, is its | |||
compactness. On average, open reading frames (ORFs) | |||
occupy 72% of the yeast genetic [excluding ribosomal | |||
DNA (rDNA), leaving little space for noncoding DNA | |||
anti for all other structural and functional elements. | |||
==Cell structure and metabolism== | ==Cell structure and metabolism== |
Revision as of 15:25, 27 August 2007
A Microbial Biorealm page on the genus Saccharomyces cerevisiae
Classification
Higher order taxa
Domain: Eukarya
Kingdom: Fungi
Subkingdom: Dikarya
Phylum: Ascomycota
Subphylum: Saccharomycotina
Class: Saccharomycetes
Order: Saccharomycetales
Family: Saccharomycetaceae
Genus: Saccharomyces
Species: Cerevisiae
Species
Taxonomy of Saccharomyces cerevisiae |
Major Strains of Saccharomyces cerevisiae
While S. cerevisiae contains many different strains used in research, below are some of the strains most commonly used in laboratories. The choice of which strain to use depends on what part of the organism is being studied.
S288c: This strain was isolated in the 1950's by Robert K. Mortimer through genetic crosses. It was used as a parental strain when isolating mutants (1). S288c was the strain used when the genome of S. cerevisiae was fully sequenced in 1996. However, its low rate of sporulation and the lack of protein growth in the absence of nitrogen prompted scientists to pick alternative strains for their research.(2)
A634A: Used in cell cycle studies. It is also closely related to S288c due to a cross with S288c and another unknown strain. (10)
BY4716: Since this is nearly identical to S288c, it is often used as a reference or control stain. (7)
CEN.PK: In Europe, this is used as a secondary reference strain alongside S288c when studying the yeast genome. Additionally, it can grow well on several different carbon sources as well as under anaerobic conditions. It is used when studying rates of growth and product formation.(3)
∑1278b: What distinguishes this strain is that it contains genes unique for nitrogen metabolism. (8). It is best studied when nitrogen is limited; cells become elongated and undergo a unique budding pattern where cells remain physically attached to each other. This is known as pseudohyphal growth. (8)
SK1: Because this strain produces lots of spores, it is used in meiotic studies. (5)
W303: Closely related to S288c due to a cross between S288c and an unknown strain, (3), it is used in genetic and biochemical analysis. (4).
Description and significance
Describe the appearance, habitat, etc. of the organism, and why it is important enough to have its genome sequenced.
Describe how and where it was isolated.
Because of its role in fermentation, humans have known about and used Saccharomyces cerevisiae for a long time. Archaeologists have found evidence of a fermented beverage in China as early as 7000BC (1), and evidence of the yeast being used in fermentation was found in a wine jar dating back to 3150BC(2). However, the first successful isolation of the species did not occur until 1938, when Emil Mrak
Saccharomyces cerevisiae was first isolated in 1938 by Emil Mrak. Include a picture or two (with sources) if you can find them.
Genome structure
Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence? Does it have any plasmids? Are they important to the organism's lifestyle?
A most conspicious feature of the yeast genome, compared with that of multicellular organisms, is its compactness. On average, open reading frames (ORFs) occupy 72% of the yeast genetic [excluding ribosomal DNA (rDNA), leaving little space for noncoding DNA anti for all other structural and functional elements.
Cell structure and metabolism
Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.
Ecology
Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.
Pathology
How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms. http://jcm.asm.org/cgi/content/full/39/2/551
Application to Biotechnology
Does this organism produce any useful compounds or enzymes? What are they and how are they used?
Current Research
Enter summaries of the most recent research here--at least three required
References
Edited by Isabella Ballesta, student of Rachel Larsen