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Information about the ASM General Meeting, and other meetings of interest.

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Instructions on assembling icosahedra, links to web sites about teaching, books, and more.

Phage facts & portraits
Information about and micrographs, diagrams, or other images of specific phages.

Links to other sites on the World Wide Web that are primarily about bacteriophages or generally about viruses.

  • The practical phage
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  • Phage art
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  • Phage know the secrets of life

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This web site was created by Division M, which is responsible for its contents.
This web site is supported by ASM and the Membership Board.

Created 1/25/98, revised 7.17.00

Please send comments or corrections to Susan Godfrey ssg1@pitt.edu or
Roger Hendrix rhx@pitt.edu.

Copyright 1998 American Society for Microbiology, all rights reserved.

A mob of bacteriophage lambda attacking E. coli

EM of Lambda attacking coli The oval object that stretches diagonally across the micrograph top-to-bottom is a single bacterium. The much smaller and far more numerous round guys, practically paving the surface of the bacterium, are the bacteriophage heads.

Tails are mostly invisible because the staining is too dense near the bacterium to reveal such slender things. At the edges of the bacterium, however, you can see that the heads are positioned about a tail-length away from the bacterial surface. The tail tip is the part that actually adsorbs to the bacterial receptor at the surface. A phage with visible tail appears at the right of the bacterium, a little distance away where the stain is lighter, towards the bottom of the image.

A bacterium might find itself similarly beleaguered in the middle of a growing bacteriophage plaque. However in Nature the proportion of phage to bacteria is probably most often much lower, and in laboratory experiments one usually attempts to infect bacteria with only a few phage, since the kind of attack pictured would be likely to kill the bacterium before it can produce new phage or generate your experimental data.

The electron micrograph shown at left is by
Roger Hendrix. (University of Pittsburgh)

The phage facts pages of this site give more information about lambda , and a close-up of the bacteriophage