Imagine this scenario. You sit at your computer to study the structure of a crucial protein--one that you've painstakingly cloned, produced in a protein-expression system, and purified after many hours in the laboratory. The crystallography laboratory that you collaborate with produced crystals of your protein weeks ago. They collected X-ray diffraction data and plugged it into their workstation-based molecular-modeling system, coming up with a three-dimensional structure of your protein showin

Advanced Biotechnologies Inc. Columbia, MD Advanced Genetic Technologies Corp San Diego, CA Ahlstrom Filtration Inc. Mount Holly Springs, PA American Bioanalytical Inc. Natick, MA Boehringer Mannheim Corp. Indianapolis, IN P.J. Cobert Associates St. Louis, MO Crescent Chemical Inc. Hauppauge, NY DuPont NEN Boston, MA Fluka Chemical Corp. Ronkonkoma, NY Gallard-Schlesinger Industries Inc. Carle Place, NY Hoefer Scientific

Advanced Biotechnologies Inc. Columbia, MD Advanced Genetic Technologies Corp San Diego, CA Ahlstrom Filtration Inc. Mount Holly Springs, PA American Bioanalytical Inc. Natick, MA Boehringer Mannheim Corp. Indianapolis, IN P.J. Cobert Associates St. Louis, MO Crescent Chemical Inc. Hauppauge, NY DuPont NEN Boston, MA Fluka Chemical Corp. Ronkonkoma, NY Gallard-Schlesinger Industries Inc. Carle Place, NY Hoefer Scientific

Molecular biologists and biochemists these days are focusing an increasing share of their investigations on the activities of a class of small peptide messenger molecules called cytokines. The following companies provide a broad array of cytokines and related products for use in biological research laboratories. For more information, please use the Reader Service Card inserted in this issue. Accurate Chemical & Scientific Corp.

Molecular biologists and biochemists these days are focusing an increasing share of their investigations on the activities of a class of small peptide messenger molecules called cytokines. The following companies provide a broad array of cytokines and related products for use in biological research laboratories. For more information, please use the Reader Service Card inserted in this issue. Accurate Chemical & Scientific Corp.

SUPPLIERS OF PIPETTES, MICROCENTRIFUGE TUBES, AND OTHER PLASTIC LABWARE Action Scientific P.O. Box 765 Forest Hill, Md. 21050 Circle No. 062 on Reader Service Card Analtech Inc. P.O. Box 7558 Newark, Del. 19714 Circle No. 063 on Reader Service Card Ashton Pumpmatic 3306 Encrete Lane Dayton, Ohio 45439 Circle No. 064 on Reader Service Card Becton Dickinson/ Falcon Labware 1 Becton Dr. Franklin Lakes, N.J. 07417 Circle No. 065 on

SUPPLIERS OF PIPETTES, MICROCENTRIFUGE TUBES, AND OTHER PLASTIC LABWARE Action Scientific P.O. Box 765 Forest Hill, Md. 21050 Circle No. 062 on Reader Service Card Analtech Inc. P.O. Box 7558 Newark, Del. 19714 Circle No. 063 on Reader Service Card Ashton Pumpmatic 3306 Encrete Lane Dayton, Ohio 45439 Circle No. 064 on Reader Service Card Becton Dickinson/ Falcon Labware 1 Becton Dr. Franklin Lakes, N.J. 07417 Circle No. 065 on

Life Technologies P.O. Box 6009 8451 Helgerman Court Gaithersburg, Md. 20884 (301) 840-4150 Fax: (800) 331-2286 MGM Instruments Inc. 925 Sherman Ave. Hamden, Conn. 06514 (203) 248-4008 Fax: (203) 288-2621 Nordic Immunological Labs Drawer 2517 Capo Beach, Calif. 92624 (714) 498-4467 Fax: (714) 361-0138 Organon Teknika/ Biotechnology Research Institute 1330 Piccard Dr. Rockville, Md. 20850-4396 (800) 354-0809 Fax: (301) 840-2161

When the Exxon Valdez ran aground in March 1989, spilling millions of gallons of crude oil into Alaska's Prince William Sound, it precipitated one of the largest bioremediation projects ever undertaken. A team of scientists from Exxon Corp., the Environmental Protection Agency, and the state of Alaska infused the contaminated beaches with nutrients to speed the growth of native oil-eating microbes, accelerating their metabolism of oil. Exxon and EPA cleaned miles of beaches, and they generated

In 1990, scientists at IBM Corp.'s Almaden Research Center in San Jose, Calif., used the minute tungsten probe of a scanning tunneling microscope to move atoms of xenon around on a nickel surface, ultimately spelling out the letters I-B-M (Nature, 344:524-6, 1990). This remarkable feat of engineering opened up an entirely new realm of applications for this microscope, which was designed to image atomic-sized specimens, not push them around. Since the first transmission electron microscope wa

Hosts of new applications have turned the light microscope into an exquisitely sensitive measuring device that can be used to image dynamic cellular events right down to the molecular level. Indeed, dramatic improvements in optical microscopy have brought about a renaissance in the use of light microscopes in biology and medicine. And within the last few years, the combination of novel optical systems with video and digital image processing capabilities have opened up whole new fields of resear

Peptides--the amino acid chains that make up proteins--were long relegated to a sideline of the much larger field of protein chemistry. But over the last few decades, their importance has grown as the understanding of these biological building blocks has become essential to a multitude of sciences, from agriculture to therapeutics to the Human Genome Project. As peptide chemistry continues to make its way into other disciplines, it behooves researchers from these disciplines to gain a basic gro