Alpha-complementation is the most common form of insertional inactivation. In alpha-complementation, the vector molecule contains the regulatory and coding regions for the first 146 amino acids of the ß-galactosidase (lacZ) gene.
E. coli strain in which only the region of the lacZ gene coding for the carboxy-terminal portion of ß-galactosidase is present. In cells that contain a vector without an insert, the amino-terminal ß-galactosidase subunit will interact with the carboxy-terminal ß-galactosidase subunit to form an active ß-galactosidase enzyme (the inducer IPTG is often necessary for transcription). ß-galactosidase catalyzes the transformation of the clear substrate X-GAL into a blue precipitate, giving colonies with an active ß-galactosidase protein a distinctive blue color. In contrast, clones containing a polycloning site into which a piece of exogenous DNA has been inserted (i.e., recombinant clones) will not produce a functional amino-terminal subunit, and will consequently appear white in color. It is the recombinant clones that are of interest, and hence they are preferentially selected from agar plates for further analysis.
Hope you find this video helpful. In case you have any doubts please feel free to ask in comments. I keep checking comments and reply to them.
If you liked this video, please do like, share and subscribe. :)
Thanks for watching.
Related videos:
Blue White Screening | CSIR NET- Life Sciences | GATE Exam: • Blue White Screening |...
Gene Cloning concepts - CSIR NET Life-sciences | GATE Exam :
• Recombinant DNA Techno...
DNA Cloning Part 3 - DNA Modifying Enzymes | Nucleases • DNA Cloning Part 3 - D...
DNA Cloning Part 4 - Restriction Endonucleases • DNA Cloning Part 4 - R...
DNA Cloning Part 5 - Linkers and Adaptors | DNA ligation | Recombinant DNA Technology | In Hindi • DNA Cloning Part 5 - L...
Subscribe: www.youtube.co...
Telegram: t.me/baayo_cha...
Facebook Group: / baayo
Facebook Page: / baayo-377840. .
Unacademy: unacademy.com/...
LinkedIn Page: / baayo
LinkedIn Profile: / artirani
Thank you :)
26 сен 2024
