Enzyme mapping

Fig. 2. Partial restriction enzyme map of plasmid pAMD 101. The blackened segment shows A. bronchisepticus DNA of 1.2 kb...

Figure 21.9 The mitogen-activated protein kinase cascade (MAP kinase cascade). The active protein Ras activates Raf by promoting its recruitment to a cell membrane. Through a series of phosphorylations MAP kinase is activated as follows MAP kinase kinase kinase (Raf) phosphorylates MAP kinase kinase which, in turn, phosphorylates MAP kinase, the final target enzyme. MAP kinase phosphorylates transcription factors for genes that express proteins involved in proliferation. Another nomenclature for the enzymes is also used raf is MEKK MAPKK is MEK and finally ERK is MAP kinase (ERK is the abbreviation for extracellular-signal-related kinase) For comparison, the reader is referred to the metabolic phosphorylase cascade, which is discussed in Chapter 12 (Figure 12.12).

The calibration of the E. coli genetic map in minutes was a temporary expedient. It was followed by physical maps expressed directly as micrometers of DNA length (total length 1.6 mm) or thousands of nucleotide units (kb). A physical map obtained by restriction enzyme mapping is shown in Fig. 26-4B. To obtain this map DNA fragments were prepared using specific restriction endonucleases (Section E, 1). 

Electrophoretic analyses of restriction enzyme digests and construction of a restriction enzyme map (see Experiment 15)... 

Blair, D. and McManus, D.P. (1 989) Restriction enzyme mapping of ribosomal DNA can distinguish between fasciolid (liver fluke) species. Molecular and Biochemical Parasitology 36, 201-208. 

Kaukas, A., Johnston, D.A., Kane, R.A. and Rollinson, D. (1994) Restriction enzyme mapping of ribosomal DNA of Schistosoma spindale and 5. leiperi (Digenea) and its application to interspecific differentiation. Systematic Parasitology 27, 13-1 7. 

Figure 22.4 Restriction enzyme map of a 21.5 kilobase (kb) DNA fragment from Pseudomonas strain ADP (adapted from de Souza et al., 1995).a...

Collections of tools for DNA and Protein sequence analysis, searching and presentation. Supports restriction enzyme mappings, open reading frames, primer design, sequence alignment, property calculations. 

To try and enhance yields of speciality chemicals, attention has focused on use of plant trichomes, the glands directly producing or accumulating oils and chemicals that are typically used to protect plants from predation. Genetic and enzymic mapping of such cells has started to identify opportunities to enhance their productivity. Examples include enhancement of alkaloid biosynthesis in opium poppy trichomes (Ounaroon el al., 2003). 

Restriction enzyme mapping 5 -end labelling fragments Sequencing by Maxam -Gilbert method... 

Example 2 Enzyme Mapping Studies by Use of P450 Isozyme Selective Inhibitors... 

At the DNA level, the isolated genes are dissimilar. For example, in wheat leaf and wheat endosperm, there is only 55.7% identity (Olive et al., 1989) and, on the basis of Southern blot hybridization analyses and restriction enzyme mapping, it is concluded that there are at least two distinct gene families in wheat. For spinach leaf and rice endosperm, there is only approximately a 50% identity (B. S. White and J. Preiss, unpublished results, 1998). 

Restriction enzyme map of a-globin gene cluster and some of the deletions (indicated as dark lines). 

Restriction enzyme map of Filipino-type deletion in ot-globin gene cluster. 

The chemical properties of the platinated DNA, termed M13-12A-Pt(-)-Stu I, were investigated by enzymatic, digestion and gel electrophoresis experiments. Platinum completely inhibits cleavage of the DNA by Stu I, as expected from the earlier restriction enzyme mapping studies. In addition, the cis-[Pt(NH3)2 d(pGpG) ] and cA-[Pt(NH3)2 d(pApG) ] intrastrand crosslinks were... 

You have just cloned an EcoRl fragment that is 1650 base pairs Obp) and contains the gene for the hormone leptin. Your first job is to prepare a restriction enzyme map of the recombinant plasmid. You know that you have cloned into a plasmid vector that is 805 bp and that has only one EcoRl site (the one into which you cloned). There are no other restriction enzyme sites in the plasmid. The following table shows the restriction enzymes used and the DNA fragment sizes that result. Draw a map of the circular recombinant plasmid and a representation of die gel from which the fragment sizes were obtained. 

One such plasmid is pBR322. The restriction enzyme map of pBR322 is illustrated in Figure 24.22. This plasmid has two antibiotic resistance genes one for ampicillin and one for tetracycline. Within the antibiotic resistance genes are several restriction enzyme sites that are convenient for cloning. 

---