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Microorganisms: Applications in Molecular Biology

  1. Jill B Keeney

Published Online: 21 DEC 2007

DOI: 10.1002/9780470015902.a0000971.pub2



How to Cite

Keeney, J. B. 2007. Microorganisms: Applications in Molecular Biology. eLS. .

Author Information

  1. Juniata College, Huntingdon, Pennsylvania, USA

Publication History

  1. Published Online: 21 DEC 2007
Table 1. Applications of media types
Media typePurpose
Solid mediaUsed to isolate colonies originating from a single cell (or clone)
Liquid mediaUsed to grow cells to logarithmic growth phase, for transformation or for isolating nucleic acid and protein
Rich mediaCells grow more quickly as compared to minimal media. No selection for added recombinant DNA
Minimal mediaCells tend to grow slower than in rich media. Allows selection for recombinant DNA containing metabolic enzymes that are mutated in the host cell
Antibiotic-containing mediaAllows selection for recombinant DNA containing an antibiotic resistance gene
Table 2. Comparison of genomes of several commonly studied organisms
OrganismApproximate size of genome (in Mbp or millions of base pairs)Number of chromosomesApproximate number of proteinsYear when first sequence completed
  1. Source: Information compiled from

Bacterium: E. coli5142001997
Yeast: S. cerevisiae121658001996
Fruitfly: Drosophila melanogaster180419 7002000
Mouse: Mus musculus30002027 2952002
Human: Homo sapiens30402328 7001999
Flowering plant: Arabidopsis thaliana119532 8002000