Sorbitol MacConkey agar which is a variant of traditional MacConkey agar can be used to isolate E. coli from a polymicrobial culture.
if you wanted to isolate E. coli from a polymicrobial culture, what would be the best...
2a. (4 pts) A potent mutagen was added to an E. coli culture growing in rich broth. Prior experiments established that this F cell line, designated WWU113, could not synthesize leucine. You are interested in measuring the rate of induced reverse mutation. You plan to grow a liquid culture of the leu strain and then plate various dilutions of the culture onto selective media. What media should you use to grow up the liquid culture? This will be Media A...
While working in a research lab, your summer student may have contaminated your E. coli sample with a Gram positive organism. Using the BD Media Manual (BD Difco and BBL culture media manual 2nd Ed), 1) List the media you would use to isolate your E. coli, and 2) state the expected colony characteristics on that media since E. coli can ferment lactose. Remember that E. coli is a Gram negative, lactose fermenting bacteria.
The adaptation phase for the E. coli culture lasted A culture of E. coli was grown on suitable culture media; aliquots of the culture were serially diluted and spread plated aseptically on agar plate media at the times indicated in the table below. Upon overnight incubation at 37°C, colonies appeared and viable counts were colleted and displayed below. Hours 0 Viable Counts (CFU/mL) 2 .00 x 107 2.10 x 107 2.30 x 107 3.25 x 107 6.60 x 107 1.40...
An E. coli culture is grown in a variety of very rich media. With a number of the media you are able to reduce the generation time to 20 mins. No further additions to the media reduce the doubling time below 20 mins. The supply of nutrients and building blocks are not limited. What factors could be limiting the growth rate of the cell?
6. Transposon mutagenesis was performed to identify genes that are involved in the biosynthesis of theA amino acid alanine. A wildtype culture of E. coli was infected with a defective phage carrying Tn10 A and the culture was plated on LB-tet media to obtain tet-resistant colony forming units. (LB is a rich growth media for E. coli and contains all amino acids required for bacterial growth) Individual CFU were then transferred to a multiwell plate containing liquid LB-tet media and...
Question 4 "A culture of 10 bacteria of Escherichia coli has a generation time of 30 minutes at 35 degrees Celsius. After Shours at this temperature, how many bacteria would you expect to 10,240 50 "1.000 320 10,000,000,000 Question 5 Which of the following types of media would not be used to culture aerobes? reducing media selective media enrichment media o differential media complex media Question 6 Which is an indirect method of measuring microbial growth? metabolic activity microscopic count...
4) (2 pts) Explain what will happen to an E. coli culture in the following media: a. No glucose + no lactose (1 pt) b. Glucose + lactose but the cells have a supper repressor mutation (1 pt) 5) The lacZ gene codes for a protein in the lac operon. What is this protein and name its function? (2 pts)
If you have a culture of E. coli at a concentration of 5x10bacteria/mL and you infect them with phage at an MOI of 3, what concentration of phage should you use?
Suppose your professor handed you a test tube with 2.0 ml of an E. Coli broth culture in it and told you to make a 10 -1 dilution of the entire culture. Explain howyou would do this. Show your calculations.
You are characterizing a microbial community from a petroleum pipeline. Assuming that you can culture, isolate and identify all microbes present in the samples, explain the criteria you would apply to classify the microbes into any a particular domain of life.