Life Sciences and Chemistry

Brown scientists have described a previously unknown but critical blood-clotting role for Arp2/3, a complex of seven proteins found in animal and plant cells.

Reporting in the June 15 issue of Blood, the scientists show that Arp2/3 complex is a cellular machine that drives a human blood platelet to change shape into a larger, more flattened form and begin the process of clotting. The link between what happens at the surface of a platelet and the mechanism of shape change within it has mystif

Pulses of laser light can make molecules react in ways that are impossible using classical test-tube chemistry. Molecules vibrate, and each molecule has its own “tone,” its own “melody.” It’s a question of finding the right key, and that is something that a “smart” laser beam can do. It can find its way to the right tone. In a new issue of the prestigious journal Nature it is shown how such a laser can be used to control photosynthesis molecules that gather light. This is the first time this fea

A tiny methane-producing microbe has revealed the existence of a new amino acid, researchers report. Two studies published in the current issue of the journal Science describe pyrrolysine, a nonstandard amino acid encoded in the RNA of bacteria-like members of the group Archaea. The findings suggest that the genetic code may be more adaptable than previously believed.

When scientists first began to unravel the genetic code more than four decades ago, they determined that the four DNA bases

A study of birds on Pacific islands shows conclusively that the formation of new species is a gradual and not a sudden process, according to biologists from the UK, France, Australia and the USA writing in the Proceedings of the National Academy of Sciences today (28 May issue).

The `founder effect` theory, a controversial idea among biologists, says that speciation occurs suddenly due to a small influx of colonists founding new populations, in the process creating many new gene combinations

This month, Journal of Applied Microbiology publishes a ground-breaking study demonstrating that bacteria which are physically separated can transmit information through the air. It is well documented that bacteria can exchange messages by releasing substances into a surrounding liquid culture medium, but this new study is the first to demonstrate signalling between physically separated bacterial cells.

Professor Alan Parsons and Dr Richard Heal of QinetiQ ltd, have shown that physically sep

A signature of arts and crafts sessions, the Möbius strip–a seemingly endless ribbon with only one side and one edge that can be made from construction paper and sticky tape–has been given a new look. According to a report published today in the journal Nature, scientists have succeeded in growing crystals in the form of Möbius structures.

A piece of ribbon or paper can be twisted and turned easily, so a regular Möbius strip itself is no great feat of engineering. Crystals, in contrast,