SESIÓN 04 METABOLISMO Y GENÉTICA DE LAS BACTERIAS. OBJETIVOS: Flashcards
What are some minimum requirements for bacterial growth?
- Source of carbon, Nitrogen, water, an energy source, and various ions.
What is an obligate anaerobe?
- Cannot tolerate O2.
What is an obligate aerobes?
-O2 is essential.
What is a facultative anaerobes?
- Can grow in both O2 and absence of it.
What are plasmids?
- extrachromosomal genetic elements.
What are bacteriophages?
- Bacterial viruses
What does the sigma factor do?
- Begins the process of transcription, recognizes a particular sequence of nucleotides in the DNA(the promoter) and binds tightly to this site to provide a docking site for the RNA polymerase.
What is a silent mutation?
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- Change at the DNA level that does not result in any change in amino acid in the encoded protein
What is a missense mutation?
- Results in different amino acids being inserted in the protein.
What is a conservative mutation?
-A missense mutation but the new amino acid has similar properties to the original one.
What is a nonsense mutation?
-Change in a codon ending an amino acid to a stop codon.
What are conditional mutation?
-Things like temperature-sensitive mutation where structure or function of an important protein change at elevated temperatures.
What is a frameshift mutation?
- A small deletion or insertion that is not in multiples of three. Results in change in reading frame, usually leading to a useless peptide and premature truncation of a the protein.
What is a null mutation?
- Completely destroy gene function, arises when there is an extensive insertion, deletion or gross rearrangement of the chromosome structure.
What are the five repair mechanisms of DNA in bacteria?
- Direct DNA repair
- Excision repair
- Recombinational or postreplication repair
- SOS response
- Error-prone repair
- Direct DNA repair
