Time-of-entry mapping

 (a) Recombinants are identified by screening exconjugants for donor allele acquisition at regular intervals and plotting their time of entry into the exconjugant chromosome. (b) Donor alleles leu+ and thr + appear in exconjugants within 4 minutes of conjugation initiation. Other donor alleles follow according to their order on the chromosome. (c) The Hfr chromosome time-of-entry map is assembled from the recombinant data (a) Recombinants are identified by screening exconjugants for donor allele acquisition at regular intervals and plotting their time of entry into the exconjugant chromosome. (b) Donor alleles leu+ and thr + appear in exconjugants within 4 minutes of conjugation initiation. Other donor alleles follow according to their order on the chromosome. (c) The Hfr chromosome time-of-entry map is assembled from the recombinant data

(a) Donor allele appearance 100 azi 8 ton a O 8 la: ° gal thr’ Ieu‘ str“ recombinants (96) N 0 Frequency of Hfr markers among 0 10 20 30 40 SO 60 Conjugation time (minutes) (b) Conjugation progression gar 5159!-.- __E;s.e_'l,, z”. “\ ’ \\ o 5 ’5 a 0-! 2 :5, 1o 0 .§ .. C .9 .. 8 g 15 5 16 U 20 25 (c) Hfr chromosome map oCir/ea thr azi ton lac gal Map W" ll 7’ """"" " ’