Bacterial transformation

What is transformation/genetic compentance

The uptake and recombination of DNA from the enviroment

What is conjugation?

transfer of DNA from a donor to a reciept via direct cell to cell contact

What is induced compteance?

Microorganisms that are not naturally competant under all physiological conditions

What is an auxotroph?

A nutritionally deficient mutant strain

What is a prototroph?

Can grow on minimal medium because it has full complement of biosynthetic capabilities

You have tow versions of the same strain of E. coli. One is wild type and ther other is a phage lambda lysogen. If you prep soft agar lawns of each strain and incoulate each with a drop of wild type phage lambda, what are the expecting plaquing phenotypes?

The phage lamba lysogen will have clear plaques and the wild type will have turbid plaques

In the transformation expreriment we used prototrophy as a selectable genetic marker to distinguish between strains. What is anotehr selectable marker?

Growth on acetate as a sole carbon source.

How can you experimentally detect the presence of AHL (acyl homoserine lactose) signal metabolites?

The mutant chromobacterium violacium (that doesn't produce AHL but can produce violaciuem by responding to AHL) should accumulate AHL signals from normal c. violacium and produce a purple pigment which would be a positive result for AHL signals.

What is R factor?

Plasmids that have resistance genes that encode enzymes that either degrade antibiotics or encode for effux pumps to transport antibiotics out

After inoculating Bacillus onto starch agar to test for its ability to hydrolyze starch what needs to be done to complete this assay and what is a postive result?

Iodine needs to be added to the plate. and a yellowish zone of clearing surrounding the inoculum in an otherwise blue plate is a postive result.

What does it mean for an antibiotic to be bacteriostatic?

Only inhibits growth of the organism (the antibiotic) it affects. The opposite would be bactercidial which would kill the antibiotic

What is an obligate oligotroph?

an organism that thrives in environments with extremely low nutrient concentrations and cannot grow well in nutrient-rich conditions.