However, because secondary structures typically form within milliseconds after the start of the folding reaction, their efforts were hampered by not having an instrument that could accurately monitor structure formation in such a short time scale. To overcome this limitation, Morishima and coworkers at Kyoto University in Japan have developed an instrument that can monitor this rapid secondary structure formation. The authors used this instrument to study folding of a small protein called cytochrome c that contains mostly alpha-helices, and they demonstrated that most of the helices are established within half a millisecond after the beginning of the folding process. At this time, the protein has not yet reached it final three-dimensional structure. Syun-Ru Yeh and Denis Rousseau of Albert Eistein College of Medicine, USA, discuss these results in an associated News and Views.
Insects can be a serious problem for agriculture, and thus pest control is big business.
Because of increasing resistance of insects to chemical pesticides, as well as growing awareness of the environmental damage caused by such pesticides, research is ongoing to find new insect control strategies. It has been suggested that using such toxins may be a more 'environmentally friendly' method of pest control. However, in the venom of a predator, insect-specific toxins can sometimes be mixed in with other toxins that are capable of killing other kinds of animals. Now, Glenn King, of the University of Connecticut in the USA, and coworkers have characterized a new family of insect-specific protein toxins from the funnel web spider Hadronyche versuta. This kind of structure has not been seen in many other proteins, and King and coworkers show that it is important for the toxin's insect-killing activity.