You are given two strains of E. coli. The Hfr strain is arg+ ala+ glu+ pro+ leu+ T s; the F− strain is arg − ala− glu− pro−leu− T r. All the markers are nutritional except T, which determines sensitivity or resistance to phage T1. The order of entry is as given, with arg+ entering the recipient first and T slast. You find that the F− strain dies when exposed to penicillin (pens), but the Hfr strain does not (penr). How would you locate the locus for pen on the bacterial chromosome with respect to arg, ala, glu, pro, and leu? Formulate your answer in logical, well-explained steps, and draw explicit diagrams where possible.

You are given two strains of E. coli. The Hfr strain is arg+
ala+ glu+ pro+ leu+ T
s
; the F− strain is arg
− ala− glu− pro−
leu− T
r
. All the markers are nutritional except T, which
determines sensitivity or resistance to phage T1. The order of entry is as given, with arg+ entering the recipient
first and T
s
last. You find that the F− strain dies when exposed to penicillin (pens
), but the Hfr strain does not
(penr
). How would you locate the locus for pen on the bacterial chromosome with respect to arg, ala, glu, pro, and
leu? Formulate your answer in logical, well-explained
steps, and draw explicit diagrams where possible.