BCH5425 Molecular Biology and Biotechnology
Spring 1998
Dr. Michael Blaber

Lecture 33

M13 Phage

The bacteriophage known as "M13" forms the basis of cloning systems designed to easily introduce mutations into genes inserted into the phage genome. It also has been used in various "phage display" methodologies and "combinatorial" DNA and peptide libraries.

M13 infection and replication

M13 is a filamentous bacteriophage which infects E. coli host. The M13 genome has the following characteristics:


Amplification of viral genome

Phage packaging

Development of M13 into a cloning vector

M13 was developed into a useful cloning vector by inserting the following elements into the genome:

Cloning into M13mp vectors

Single stranded forms of the phage

The ability to isolated a single stranded form of the phage has advantages in both sequencing and mutagenesis.

An efficient mutagenesis method (the "Kunkel" method) was developed using the single stranded form of the phage.

1998 Dr. Michael Blaber