What is restriction mapping of DNA?
Restriction mapping is a method used to map an unknown segment of DNA by breaking it into pieces and then identifying the locations of the breakpoints. This method relies upon the use of proteins called restriction enzymes, which can cut, or digest, DNA molecules at short, specific sequences called restriction sites.
Why do we map plasmids?
Mapping of DNA restriction sites is an important part of working in a molecular biotechnology lab because such maps are used to plan cloning strategy and to verify when a DNA clone has been successfully constructed.
How do you find the number of restriction fragments?
The frequency of occurrence of AGCT in the DNA is 1-in-256 bases. Dividing 1×1000 bp by 256 gives 4 as the nearest whole number. Add 1, because the DNA is linear (compare cutting a rubber band with cutting a shoe lace). This gives a total of 5 restriction fragments.
What is the purpose of plasmid mapping?
Plasmid maps are graphical representation of plasmids, that show the locations of major identifiable landmarks on DNA like restriction enzyme sites, gene of interest, plasmid name and length etc.
What is the importance of restriction mapping?
Restriction enzyme mapping is a powerful tool for the analysis of DNA. This technique relies on restriction endonucleases, hundreds of which are now available, each one recognizing and reproducibly cleaving a specific base pair (bp) sequence in double-stranded DNA thus generating fragments of varying sizes.
Why is it important to create a restriction map?
Restriction mapping is a helpful tool for experiments where sequencing can be out of budget or not necessary. It can be used to determine whether a gene has been cloned into the plasmid. It is a much better technique for relatively short segments of DNA.
How do you determine the size of DNA restriction fragments?
To calculate the fragment size we simply need to subtract the bp difference between the two REs: 5198 bp – 5070 bp = 128 bp. DNA fragment 2 – a large fragment (and our desired DNA fragment as it contains all the features of the plasmid.
How do you identify plasmid DNA?
Linear Plasmid You can identify the linear DNA form on an agarose gel by comparing uncut plasmid DNA with a sample of the plasmid that has been linearized using a restriction enzyme.