Maxam-Gilbert method

The base-specific chemical cleavage (or Maxam-Gilbert) method starts with a single-stranded DNA that is labeled at one end with radioactive (Double-stranded DNA can be used if only one strand is labeled at only one of its ends.) The DNA strand is then randomly cleaved by reactions that specifically fragment its sugar-phosphate backbone only where certain bases have been chemically removed. There is no unique reaction for each of the four bases. However,... 

In principle, the Maxam-Gilbert method can provide the total sequence of a dsDNA molecule just by determining the purine positions on one strand and then the purines on the complementary strand. Complementary base-pairing rules then reveal the pyrimidines along each strand, T complementary to where A is, C complementary to where G occurs. (The analogous approach of locating the pyrimidines on each strand would also provide sufficient information to write the total sequence.)... 

The Maxam-Gilbert method doesn t require synthesis of a primer and it sometimes works well for sequences that are difficult to obtain with the Sanger -Coulson procedure. The two methods may both be used to provide additional certainty about a sequence. The Maxam-Gilbert method is very convenient for sequencing small oligonucleotides which often react poorly with the polymerase used for the chain termination method. The method usually requires that a restriction map be prepared. 

Sequence analysis of nucleotides by the Sanger or Maxam-Gilbert method... 

These procedures share with the Maxam-Gilbert chemical procedures the requirement for a 5 -end labelled DNA but are clearly only applicable to a duplex molecule. As the procedure is relatively simple and rapid it may well be worth using as an adjunct to the Maxam-Gilbert method (Chapter 5). 

Maxam-Gilbert method (Cordell et al., 1979 Buchel et al., 1980 Czemilofsky et al., 1980). With viral DNA up to 6 times the length of M13, however, deletions may occur within the cloned DNA (Messing, unpublished). 

Chain extension with reverse transcriptase. Sequence by Maxam -Gilbert method (chapter 5)... 

The final point to note is that sequencing by the primed synthesis methods will not reveal the presence of methylated or other modified nucleotides in the original DNA sequence. This is also true of the Maxam-Gilbert method where the DNA to be sequenced has been cloned into a plasmid vector. 

The Maxam-Gilbert method for DNA sequencing depends upon (one of the following) ... 

DNA sequencing Maxam-Gilbert method restriction endonuclease restriction fragment palindrome Sanger dideoxy method DNA synthesis DMT ether phosphoramidite phosphite polymerase chain reaction (PCR)... 

Figure 5-20. DNA sequencing by the Maxam-Gilbert method. End-labelled DNA is treated in four separate aliquots with chemical reagents which cleave specifically after A, G, C+Tand C. The fragments generated by partial chemical...

C. The Maxam-Gilbert method uses a lot more sample. 

Small DNA segments can be synthesized in the laboratory, and commercial instruments are available for automating the work. Sequencing of DNA can be carried out either by the Maxam-Gilbert method, which uses chemical techniques, or by the Sanger dideoxy method, which uses enzymatic techniques. Small amounts of DNA can be amplified by factors of 10 using the polymerase chain reaction (PCR). 

There are five steps to the Maxam-Gilbert method of DNA sequencing. ... 

Another sequencing technique is the Maxam-Gilbert method (developed by Alan Maxam and Walter Gilbert). In this method, a single DNA strand is labeled at the 5 end with radioactive phosphorus (P ). The radioactive DNA is divided into four portions and each one is exposed to different chemical reactions. Each reaction causes a 5 cleavage adjacent to either... 

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