Genetics: Analysis of Genes and Genomes: Keyword Hot Links for chapter 9

With about 100 bacteriophage, 200 plasmid, and 50 bacterial genomes completely sequenced, merely finding the information that one seeks is not always as straightforward as it may seem. The National Center for Biotechnology Information (NCBI) maintains a site to facilitate the use of databases and software for analyzing data about genetics, molecular biology, and biochemistry. Browse the site map at the keyword NCBI and find the annotated maps of the E. coli and bacteriophage l genomes.

Available Hfr strains in E. coli can be found by searching at this site. Simply enter Hfr in the box that says "sex" and you will obtain the list. Clicking on any entry, say, 3310 Paris Hfr, will open a link to more detailed information. The entry will give you the origin of transfer of the Hfr (in this case, 96.80 minutes) and direction of transfer (1 = clockwise, 0 = counterclockwise), in this case counterclockwise, any mutant genes that are present in the strain, and one or more relevant references. Check out the "classic" Hfr strains, Hfr Hayes and Hfr Cavalli.

When bacteriophages were first discovered early in the 20th century they opened the possibility of phage therapy, or the use of specific kinds of bacteriophage to kill pathogenic bacteria. This avenue remained unexplored after the early 1940s when antibiotics were developed and began to be widely used in the treatment of bacterial infections. Today, with the spread of bacteria resistant to most or all available antibiotics causing increasing concern, phage therapy is the subject of renewed research. At this keyword site you can learn about the historical and ecological context of this research and find a realistic assessment of its prospects for success.