Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1986;49(1):119-28.
doi: 10.1016/0378-1119(86)90391-4.

A method for unidirectional deletion mutagenesis with application to nucleotide sequencing and preparation of gene fusions

A method for unidirectional deletion mutagenesis with application to nucleotide sequencing and preparation of gene fusions

G J Barcak et al. Gene. 1986.

Abstract

A method is described for the preparation of deletions that extend in one direction from a fixed point. The method is based on the ability of deoxynucleoside [1-thio]triphosphates to be incorporated into DNA by DNA polymerase I, Klenow fragment, and the fact that alpha-thiophosphate-containing phosphodiester bonds are resistant to hydrolysis by the 3'-to-5' exonucleolytic activity of phage T4 DNA polymerase. Therefore, linear duplex DNA molecules blocked at one 3'-terminus with a thiophosphate were prepared and then degraded from the other end with the exonuclease. Digestion for different lengths of time followed by treatment with nuclease S1 and ligation allowed the preparation and recovery of a nested set of deletion mutants. Importantly, it was observed that a significant fraction of deletion mutants of recombinant M13 phages carrying the target gene in the same orientation as 'lacZ alpha' yielded phage that produced lacZ alpha-complementing activity. Nucleotide (nt) sequencing showed that these phages carried in-frame fusions between the target gene and 'lacZ alpha'. The deletion mutagenesis procedure is applied to the nt sequencing of a gnd gene from a natural isolate of Escherichia coli.

PubMed Disclaimer

Similar articles

Cited by

Publication types

Substances

LinkOut - more resources