Question

Assuming that you observed similar patchy bacterial growth pattern in plates "B-Amp, phage" and "C-LB, phage". The T4 phages greatly affected the growth of E. coli strain CR63 in the LB plate ("C-LB, phage" plate), creating a patchy bacterial growth pattern similar to the expected result in the ampicillin plate of strain BE with phage ("B-Amp, phage" plate). Besides experimental errors, describe the possible reasons why the bacterial colonies were isolated in these two plates. "B-Amp, phage" Plate (strain BE)?

Answer 1

Some bacterias show a great resistance power to fight against T4 phages That leads to great growth in the medium given that resistance power may be given by plasmids As plasmids show the resistant genes that great work in the medium.

T4 phage is a virus that shows a lytic cycle after affecting bacteria and going to kill the bacterial cells in bacterial strain So no growth in LB media. Some bacteria are sensitive due to the lack of resistant genes therefore, their growth may affect by many factors of the medium. If the bacteria are recombinant, they show greater growth in the medium.

* B-Amp, Phage plate (strain Be), there is ampicillin, so inhibits the growth of bacteria but still there is patchy growth of bacteria and they still show the growth but due to presence of phage T4, they show patchy growth.