Courtesy of Priscilla FurthScientists have tried at least four methods for delivering nucleic acids to mammalian tissues for the purpose of inducing exogenous gene expression: scarifying the epithelium with a razor blade, then smearing the skin with DNA; scratching the skin with the back of an 18-gauge needle followed by smearing on of DNA; intradermal inoculation and puncture 200 times with a 27-gauge needle; and interdermal inoculation using a jet injector. The first two techniques didn't work

Next time you plunk down $4 for a cup of gourmet coffee, consider thanking the anonymous laborers who harvested the beans that went into it. The best coffees use hand picked beans, "because the fruits of a coffee tree do not ripen uniformly and, thus, there are both mature and immature fruit on the same tree," according to a new US patent (6,727,406).A dearth of cheap labor has forced many growers to adopt methods in which workers indiscriminately harvest beans from branches, ripe or not. Mechan

One traditional gene-therapy method relies on homologous recombination. The desired gene segment is placed on a small plasmid and delivered by virus or liposome, but this approach has variable expression levels and instability, and is limited by a small insert size. Yeast artificial chromosomes circumvent some of these problems, but YACs cannot be propagated in mammalian cells. Now a team of scientists at DNAVEC Research of Ibaraki, Japan, has come up with a solution: They have developed a metho

Courtesy of XencorIf you're trying to optimize a protein's biological activity, to make it a more potent therapeutic agent, for instance, the selection process can be painstaking. Say you wanted to make one change at a time in a 200-amino acid protein. That's 200 multiplied by 19 (for the other naturally occurring amino acids that your original protein could place at that site), or 3,800 possibilities. Make two changes at a time, and you're in the millions. Make three, and you get the picture. S

With its name, it's probably no surprise that San Diego-based Nanogen http://www.nanogen.com has quickly amassed a portfolio of patents covering nanoassembly. "We were very lucky because we have incredibly early priority on this," says Nanogen cofounder Michael Heller, of a trio of now-patented nanofabrication methods.In January, Patent Watch highlighted patent 6,652,808 for a method that allows for the self-assembly of DNA particles on preformed motherboard substrates.1 Like this and the other

Conference examines origins of life on Earth, elsewhere in the universe, and the future

Courtesy of National Sciences FoundationWhat if next Valentine's Day, you could time the flowers you bought to blossom just as your spouse walked in the door? If you enjoy giving bouquets of Arabidopsis, you're in luck: A new patent held by a group at the University of Wisconsin will let you slow down the flowering of that organism. The patent (US 6,693,228) covers the Flowering Locus C1 (FLC1) gene, which contains a MADS box domain, and a method by which it is connected to an expressible promot

For those who need to express recombinant membrane proteins, the use of Escherichia coli has been problematic because these proteins are often lethal, according to Mary Lynne Collins, a professor of biology at the University of Wisconsin, Milwaukee. Collins and Yongjian Cheng were recently awarded US patent 6,680,179 for a method that allows expression of membrane proteins in Rhodospirillum rubrum, whose unique features make it an attractive host, says Collins.R. rubrum is a photosynthetic bacte

One of the problems in detecting prions is that the infectious agent is just a conformational isomer of a normal "self" protein. Typical diagnostic approaches, such as looking for tell-tale antibodies or nucleic acids, therefore won't work. The successful approach exploits conformational differences between the two protein variants, says Jiri Safar of the Institute for Neurodegenerative Diseases at the University of California, San Francisco. Safar and Stanley Prusiner, who won a Nobel Prize for

Courtesy of Henry DaniellGenetically engineered plants pose several major environmental concerns, according to Henry Daniell, a professor of molecular biology and microbiology at the University of Central Florida. When foreign genes are introduced into the nuclear genome, they end up in pollen, posing the risk of transfer to other species. And sometimes, expression levels are low.Daniell and colleagues have come up with what he says is a solution: chloroplast genetic engineering. The method R

When Nanogen was started in the early 1990s, its scientists came up with an idea: Make a microarray using an electric field-based sorting mechanism, according to cofounder Michael Heller. "It didn't escape our attention that since we were using DNA and were labeling it with all kinds of little flu-orophores and nano-particles, we were helping to assist in the assembly of DNA molecules by using the electronic methods," Heller says.It was the beginning of assisted self-assembly of individual DNA m

Techniques developed after attacks detailed at American Chemical Society meeting