Articles by Simon Silver

Microbial ice nucleation is important biotechnology for three reasons. First, preventing ice crystal formation using deletion mutants is a way to prevent frost damage; that is, "frost-ban" Pseudomads are a marketable product. Second, stimulating snow formation on artificial ski slopes extends the season; that is, ice-nucleating Pseudomonads are another marketable product. Third, the field testing of the "frost-ban" cells on strawberry plants occasioned some of the most emotional responses to rel

Author: SIMON SILVER Department of Microbiology & Immunology University of Illinois Chicago, p.19 Why do trypanosomes have mitochondrial genes that are only partial and need the insertion of dozens of uridine residues (copied from small guide RNAs)? Now a slime mold has a gene for the major ATP synthase a subunit that needs 54 insertions of cytidine to correct frame shifts from the missing bases. The mitochondrial genes of eucaryotic microbes are strange. R. Mahendran, M.R. Spottswood, D.L.

Department of Microbiology & Immunology University of Illinois Chicago GTPase mechanisms work for ras family oncogenes, vesicular transport mechanisms, signal transduction, and translational initiation and elongation in prokaryotes, eukaryotic microbes, plants, and animals. Members of the diverse GTPase group of enzymes share sequence homologies, molecular mechanisms, and structural patterns. Crystal structures (from X-ray analysis), molecular genetics, and biochemical studies merge into a

SIMON SILVER Department of Microbiology & Immunology University of Illinois Chicago New York, San Francisco, and Los Angeles accounted for nearly half the new AIDS cases in early 1985. But the number of new cases in these cities has leveled off, and new cases here now represent 75 percent of the total. New AIDS cases among homosexuals are increasing slowly, but AIDS among intravenous drug users and AIDS associated with perinatal infection are increasing more rapidly. J.M. Karon, T.J. Donde

SIMON SILVER Department of Microbiology & Immunology University of Illinois Chicago It is not the absence of two X chromosomes that makes for a man rather than a woman. The Y chromosome contains a sex-determining gene (or genes), which functions during testis differentiation. Missense and frame-shift mutations result in XY females. P. Berta, J.R. Hawkins, A.H. Sinclair, A. Taylor, et al., "Genetic evidence equating SRY and the testis-determining factor," Nature, 348, 448-50, 29 November 199

SIMON SILVER Department of Microbiology & Immunology University of Illinois Chicago Pseudopods flowing from phagocytes and amoeba constantly assemble and disassemble actin into rods and networks. This popular review of recent progress on regulation of cellular movement is full of wonderful graphics, suitable for textbooks and teaching. T.P. Stossel, "How cells crawl," American Scientist, 78, 408-23, September-October 1990. (Harvard Medical School and Massachusetts General Hospital, Boston)

SIMON SILVER Department of Microbiology & Immunology University of Illinois Chicago The hype is out of proportion, but the 12 October issue of Science spotlights the Human Genome Project with an attractive cover montage, a removable centerfold of current human chromosome maps (intended for wall display), and a status report. Real progress is being made, however, as exemplified by the promising new approaches presented in the same issue. J.C. Stephens, M.L. Cavanaugh, M.I. Gradie, M.L. Mador,

Department of Microbiology & Immunology University of Illinois Chicago The gene defective in cystic fibrosis patients was identified and sequenced last year. Now that the quite different research skills of physiology and molecular genetics groups have been put together, the wild-type normal gene has been transfected into cultured defective cells and shown to work. There still is a long, long way to go before the disease can be cured by gene therapy. Already the cloned gene will be useful in d

Department of Microbiology & Immunology University of Illinois Chicago Perhaps most of us (who live into our late 80s) will show symptoms of Alzheimer's disease. There is evidence of a familial propensity, so it is important to understand the genetic control and, through that, eventually the disease's biochemical basis. Lod ("log of the odds") scores range from significant to not significant (or back!). The results from 48 family lineages gathered by this group of 35 listed authors (plus an ad

Author: SIMON SILVER Department of Microbiology & Immunology University of Illinois Chicago The Luddites have mostly won during the 15 years of recombinant DNA research and debates. An FDA report concludes that bovine growth hormone presents no increased health risk. Yet the combination of building political bases and mounting irrational fear of genetic engineering means that we will probably continue to be protected from this unreal danger. Our students have questioning minds, so this compilat

Author: SIMON SILVER Department of Microbiology & Immunology University of Illinois Chicago Discovering six new vitamins in a single metabolic pathway is unprecedented, but then, neither methanogenesis nor Ralph Wolfe is standard. The metabolic pathway for converting CO2 to CH2, which is unique to the methanogenic archaebacteria, has shown that there is novel microbiology and metabolic biochemistry work yet to do. A.A. DiMarco, T.A. Bobik, R.S. Wolfe, "Unusual coenzymes of methanogenesis,"

The Scientist has asked a group of experts to comment periodically upon recent articles that they have found noteworthy. Their selections, presented herein every issue, are neither endorsements of content nor the result of systematic searching. Rather, the list represents personal choices of articles the columnists believe the scientific community as a whole may also find interesting. Reprints of any articles cited here may be ordered through The Genuine Article, 3501 Market St., Philadelphia,

The Scientist has asked a group of experts to comment periodically upon recent articles that they have found noteworthy. Their selections, presented herein every issue, are neither endorsements of content nor the result of systematic searching. Rather, the list represents personal choices of articles the columnists believe the scientific community as a whole may also find interesting. Reprints of any articles cited here may be ordered through The Genuine Article, 3501 Market St., Philadelphia,

The Scientist has asked a group of experts to comment periodically upon recent articles that they have found noteworthy. Their selections, presented herein every issue, are neither endorsements of content nor the result of systematic searching. Rather, the list represents personal choices of articles the columnists believe the scientific community as a whole may also find interesting. Reprints of any articles cited here may be ordered through The Genuine Article, 3501 Market St., Philadelphia,

Department of Microbiology & Immunology University of Illinois Chicago Cosy, Noesy, and HoHaHa! Respectively, these are abbreviations for two-dimensional scalar correlated spectroscopy, two-dimensional nuclear Overhauser enhancement spectroscopy, and Homonuclear Hartmann Hahn transfer experiment - three of the techniques used to study Megasphaera elsdenii. Apparently, we need to learn well the general rules for two-dimensional nuclear magnetic resonance (NMR) determination of atomic conne