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Old antiseptic, new use
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D/L
ratio of the samples, their reactivity with the two probes varied, and the degree of differential probe incorporation was measured by laser scanning to give an indication of ee. Accuracies of ±10% are possible using the technique, which is equivalent to those obtained with conventional methods such as chiral high performance liquid chromatography (HPLC). M.J.D.
GSK screens SNPs Newly merged pharmaceutical giant GlaxoSmithKline is planning to screen the entire human genome for genetic markers that are responsible for side effects caused by its own drugs. Presenting at the IBC meeting on Pharmacogenomics, SNPs and Genetic Patenting in San Diego, GSK described how it will screen 200 000 single nucleotide polymorphisms (SNPs) in an attempt to pinpont markers that can be correlated with adverse reactions to Abacavir, its anti-retroviral drug used in combination HIV therapy. The company believes that SNP screening for adverse drug effects will be cost-effective in the long term through reduced compensation claims and increased prescribing of screened drugs. M.J.D.
Making light work Researchers at the University of Wisconsin-Madison have developed a new type of chemical sensor, based on light-emitting diodes (LEDs). Reporting in Nature (25 January) the team led by Thomas Kuech and Arthur Ellis describe how exposing the surface of an LED to different substances causes the intensity of emitted light to fluctuate, in direct proportion to the amount of chemical applied. The work is part of efforts to develop ‘lab-on-a-chip’ analyses, and potential applications of the sensors could be in detection of air- or water-borne pollutants, or even biological molecules in a warzone. M.J.D.
Solid-phase sugars First peptides, then oligonucleotides and now oligosaccharides. In the 1 February online issue of Science, chemists at MIT describe how they have adapted an existing automated peptide synthesiser to accomplish the solid phase synthesis of oligosaccharides. The MIT researchers, led
TRENDS in Biotechnology Vol.19 No.4 April 2001
by Peter Seeberger, prepared a 12-sugar oligosaccharide in 18 hours, a synthesis that would take three months using conventional methods, but predict that it will be another five to ten years before a full range sugar monomers will be routinely available for use on an automated synthesiser. M.J.D.
129
Turning leaves into flowers
Structure of protein involved in DNA transfer The determination of enzyme structure can often reveal interesting and unpredictable information not only about the function of enzymes but also about their relationships with other proteins. Such information might not be revealed by comparisons of amino acid sequence. An interesting case in point is the report by Gomis-Rüth and colleagues (Nature, 1 February) showing the relationship between a protein responsible for transferring single-stranded DNA between bacteria (TrwB) and that of proteins involved in the replication, repair, recombination and expression of DNA (such as the famous RecA), as well as in transforming energy (part of the F1F0-ATP synthase that makes ATP). One of the core structural aspects of these proteins is their organization of hexameric rings. Considering that proteins such as TrwB are a key component of the movement of DNA between bacteria (horizontal gene transfer) and provide a mechanism by which virulence factors and antibiotic resistance spread, the study of such proteins is particularly important. D.M.
Old antiseptic, new use Rima McLeod, et al (Int. J. Parasitol., February) report on the use of Triclosan, a common antiseptic used in household products such as toothpaste, skin creams and deodorants, to kill the parasites responsible for malaria and toxoplasmosis. Triclosan has been used as an antiseptic since the 1960s and blocks an enzyme, known as ‘FabI’ that bacteria need to manufacture the fatty acids used in cell membranes. Because animals possess a very different set of enzymes, triclosan does not interfere with this process in humans. The malarial FabI has the same pattern of critical amino acids that bind triclosan as the plant and bacterial variants. D.M.
Soraya Pelaz et al. (Current Biology, February) illustrate that expression of a recently discovered new class of floral genes (called SEP), together with three other genes responsible for flower development, are sufficient to convert leaves into petals. The team’s discovery has important commercial as well as scientific implications. In the report they show that, in the mustard weed, Arabidopsis, two of the SEP genes, in combination with three other genes responsible for floral development, are sufficient to convert leaves into petals. D.M.
Drafts of the human genome published The draft DNA sequences from the International Human Genome Sequencing Consortium (Nature, 15 February) and the company Celera, headed by J. Craig Venter (Science, 16 February), are here. Both sequences are about 90% complete. It’s a daunting prospect to write a ‘100-wordsor-less’ summary of the findings. However, here are some interesting titbits: (1) the small number of genes required to encode a human is astonishing – ~30 000, which is not much more than that of a plant (26 000) and roughly double that of a fly (13 000) and a worm (18 000); (2) hundreds of genes appear likely to have resulted from horizontal gene transfer from bacteria at some point in the vertebrate lineage; and (3) about half the genome derives from transposable elements. If you wish to participate in what some people claim is the biggest event in biology since the publication of the ‘Origin of Species’, go to the National Center for Biotechnology Information (NCBI) website. The Human Genome home page is: http://www.ncbi.nlm.nih.gov/genome/ guide/human. D.M.
http://tibtech.trends.com 0167-7799/01/$ – see front matter © 2001 Elsevier Science Ltd. All rights reserved.
D/L
ratio of the samples, their reactivity with the two probes varied, and the degree of differential probe incorporation was measured by laser scanning to give an indication of ee. Accuracies of ±10% are possible using the technique, which is equivalent to those obtained with conventional methods such as chiral high performance liquid chromatography (HPLC). M.J.D.
GSK screens SNPs Newly merged pharmaceutical giant GlaxoSmithKline is planning to screen the entire human genome for genetic markers that are responsible for side effects caused by its own drugs. Presenting at the IBC meeting on Pharmacogenomics, SNPs and Genetic Patenting in San Diego, GSK described how it will screen 200 000 single nucleotide polymorphisms (SNPs) in an attempt to pinpont markers that can be correlated with adverse reactions to Abacavir, its anti-retroviral drug used in combination HIV therapy. The company believes that SNP screening for adverse drug effects will be cost-effective in the long term through reduced compensation claims and increased prescribing of screened drugs. M.J.D.
Making light work Researchers at the University of Wisconsin-Madison have developed a new type of chemical sensor, based on light-emitting diodes (LEDs). Reporting in Nature (25 January) the team led by Thomas Kuech and Arthur Ellis describe how exposing the surface of an LED to different substances causes the intensity of emitted light to fluctuate, in direct proportion to the amount of chemical applied. The work is part of efforts to develop ‘lab-on-a-chip’ analyses, and potential applications of the sensors could be in detection of air- or water-borne pollutants, or even biological molecules in a warzone. M.J.D.
Solid-phase sugars First peptides, then oligonucleotides and now oligosaccharides. In the 1 February online issue of Science, chemists at MIT describe how they have adapted an existing automated peptide synthesiser to accomplish the solid phase synthesis of oligosaccharides. The MIT researchers, led
TRENDS in Biotechnology Vol.19 No.4 April 2001
by Peter Seeberger, prepared a 12-sugar oligosaccharide in 18 hours, a synthesis that would take three months using conventional methods, but predict that it will be another five to ten years before a full range sugar monomers will be routinely available for use on an automated synthesiser. M.J.D.
129
Turning leaves into flowers
Structure of protein involved in DNA transfer The determination of enzyme structure can often reveal interesting and unpredictable information not only about the function of enzymes but also about their relationships with other proteins. Such information might not be revealed by comparisons of amino acid sequence. An interesting case in point is the report by Gomis-Rüth and colleagues (Nature, 1 February) showing the relationship between a protein responsible for transferring single-stranded DNA between bacteria (TrwB) and that of proteins involved in the replication, repair, recombination and expression of DNA (such as the famous RecA), as well as in transforming energy (part of the F1F0-ATP synthase that makes ATP). One of the core structural aspects of these proteins is their organization of hexameric rings. Considering that proteins such as TrwB are a key component of the movement of DNA between bacteria (horizontal gene transfer) and provide a mechanism by which virulence factors and antibiotic resistance spread, the study of such proteins is particularly important. D.M.
Old antiseptic, new use Rima McLeod, et al (Int. J. Parasitol., February) report on the use of Triclosan, a common antiseptic used in household products such as toothpaste, skin creams and deodorants, to kill the parasites responsible for malaria and toxoplasmosis. Triclosan has been used as an antiseptic since the 1960s and blocks an enzyme, known as ‘FabI’ that bacteria need to manufacture the fatty acids used in cell membranes. Because animals possess a very different set of enzymes, triclosan does not interfere with this process in humans. The malarial FabI has the same pattern of critical amino acids that bind triclosan as the plant and bacterial variants. D.M.
Soraya Pelaz et al. (Current Biology, February) illustrate that expression of a recently discovered new class of floral genes (called SEP), together with three other genes responsible for flower development, are sufficient to convert leaves into petals. The team’s discovery has important commercial as well as scientific implications. In the report they show that, in the mustard weed, Arabidopsis, two of the SEP genes, in combination with three other genes responsible for floral development, are sufficient to convert leaves into petals. D.M.
Drafts of the human genome published The draft DNA sequences from the International Human Genome Sequencing Consortium (Nature, 15 February) and the company Celera, headed by J. Craig Venter (Science, 16 February), are here. Both sequences are about 90% complete. It’s a daunting prospect to write a ‘100-wordsor-less’ summary of the findings. However, here are some interesting titbits: (1) the small number of genes required to encode a human is astonishing – ~30 000, which is not much more than that of a plant (26 000) and roughly double that of a fly (13 000) and a worm (18 000); (2) hundreds of genes appear likely to have resulted from horizontal gene transfer from bacteria at some point in the vertebrate lineage; and (3) about half the genome derives from transposable elements. If you wish to participate in what some people claim is the biggest event in biology since the publication of the ‘Origin of Species’, go to the National Center for Biotechnology Information (NCBI) website. The Human Genome home page is: http://www.ncbi.nlm.nih.gov/genome/ guide/human. D.M.
http://tibtech.trends.com 0167-7799/01/$ – see front matter © 2001 Elsevier Science Ltd. All rights reserved.