DNA Sequence Information

Perhaps the greatest impact of rDNA technology lies in ib ability to alter a DNA sequence and create entirely new molecules that, if reintroduced into the genome, can be inherited and propagated in perpetuity. The ability to alter a DNA sequence, literally in a test tube, at the di.scretion of an individual. corporation, or nation, brings with it important questions about ownership, ethics, and social responsibility. There is no question, however, that potential benefits to the treatment of human dLsease are great. 

Ii is possible to combine elements of two proteins into one new recombinant protein. The resulting protein, refened to as a chimeric or fusion protein, may then have some ot the functional properties of both of the original proieim 

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Determination of DNA Sequence Information. Almost all DNA sequence is determined by enzymatic methods (12) which exploit the properties of the enzyme DNA polymerase. Whereas a chemical method for DNA sequencing exists, its use has been supplanted for the most part in the initial deterrnination of a sequence. Chemical or Maxam-Gilbett sequencing (13) is mote often used for mapping functional sites on DNA fragments of known sequence. 

DNA sequence information is the starting poiat for other appHcations, including the expression of a gene product, the search for related sequences ia biological samples, in vitro mutageaesis of the sequeace, and stmcture—function studies of gene expression. 

Computer-aided programs, for SLS equipment selection, 11 348 Computer analysis, of DNA sequence information, 12 510-512 piping system sizing using, 19 473-474 Computer-assisted color matching,... 

DNA polymerase enzymes, 22 509-510 DNA polymerases, 22 513 20 447 DNA population, complexity of, 22 503 DNA-protein interactions, 2 7 608 DNA replication, 22 500 DNA restriction fragments, location of specific sequences to, 22 499 DNA sequence information... 

Transcription. For expression of a gene—i. e., synthesis of the coded protein—the DNA sequence information has to be converted into a protein sequence. As DNA itself is not involved in protein synthesis, the information is transferred from the nucleus to the site of synthesis in the cytoplasm. To achieve this, the template strand in the relevant part of the gene is transcribed into an RNA (hnRNA). The sequence of this RNA is thus complementary to that of the template strand (3), but— with the exception of the exchange of thy-... 

Biomedical research is in the middle of a significant transition. The transition is driven by two primary factors the massive increase in the amount of DNA sequence information, and the development of technologies to exploit its use. Over the last few years, more than 30 organisms have had their genomes completely sequenced and another 100 or so will follow close behind (see http //www.ncbi.nlm.nih.gov for a list). Within 2002, a 90% draft of the human genome sequence will be at hand, with completion expected by the year 2003. 

From genome sequences, a plethora of DNA sequence information is, often publicly, accessible in databases. Pieces of genome sequence have often been annotated, based on sequence similarity to other genes with similar function, to possess a certain function. From the gene sequence, the corresponding protein sequence of a putative enzyme can of course be readily derived so that at this stage the target of the search for a new enzyme is defined. 

Mitotic gene conversion A phenomenon in which the unilateral transfer of DNA sequence information occurs within a gene and results in nonreciprocal products. 

The progress of peptide research was expedited by the completion of the Human Genome Project. The availability of DNA sequence information has made it possible to rapidly discover new peptides by screening DNA and expression libraries. Using bioinformatic tools (Antelmann et al., 2001 and Chen et al., 2003), numerous as yet unknown putative polypeptides have been predicted as candidates with secretory properties or as proteases. 

Eremomyces langeronii with its anamorph Arthrographis kalrae is a cleis-tothecial species whose inclusion in the Eurotiales has to be confirmed by ribo-somal DNA sequence information. The species causes an onychomycosis and is mainly isolated from human skin and nails [80, 271]. 

A final tool, the use of which will be highlighted in the next chapter, is the computer. Without the computer, it would be impossible to catalog, access, and characterize the abundant information, especially DNA sequence information, that the techniques just outlined are rapidly generating. 

Despite our knowledge of splice-site sequences, predicting splicing patterns from genomic DNA sequence information... 

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