The system may be used to perform thousands of tests to detect viruses, as well as for studies designed to find ways to stop them.
Scientists seeking to develop tests to detect viruses, or drugs or vaccines against the virus, are required, first and foremost, to know the structure of the virus being studied. But of course, when it comes to violent viruses, working with real viruses involves considerable risk. Prof. Roi Bar-Ziv, faculty scientist Dr. Shirley Shulman Dauba, research student (then) Dr. Ohad Wenshek and research student Yiftach Dibon in the Department of Chemical and Biological Physics at the Weizmann Institute of Science describe how they tackled the challenge in an original way. They created artificial cells – a kind of micrometric dimples – that were “hewn” in a silicon chip. At the bottom of the “dimples” of the artificial cells, the scientists fixed dense DNA strands. Around the “cells”, they place a kind of “carpets” of receptors that bind the proteins that the system produces. At the beginning of the process, the scientists infused the artificial cells with a solution that contained the molecules and enzymes that “read” the genetic information in the DNA strands and produce proteins based on them. In the next step – which occurs without human intervention – the receptors that the scientists have placed around the periphery of the artificial cells bind one of the virus proteins created in the cell. Later, the other virus proteins integrate with each other and together form the structures that the scientists wanted to create – in this case, small parts of a special type of virus, which attacks bacteria (“bacteriophages”). The findings of the study are published today in Nature Nanotechnology.
“We have discovered,” says Prof. Bar-Ziv, “that we can control the assembly processes, their efficiency and the products that will be assembled in our artificial cells – through careful planning and design of the geometric structure of these ‘cells’. In addition, changes in the locations of the genes and their various clusters determine, in effect, what proteins the cell produces, and subsequently, what it will make and produce from them. ” Dr. Wenshek adds: “The fact that these are ‘micrometric artificial cells’, allows us to place a huge number of artificial cells on one chip, and through a different design, cause different cells to perform different tasks in the same ‘run’.”
These features of the system developed by the Institute’s scientists and the ability to simultaneously create very many small and different parts of viruses may enable scientists, all over the world, to create and test different drugs and vaccines against it. “These experiments,” says Divon, “which are based on synthetic parts – and not on components of the real virus – will be carried out at a particularly high level of safety.” “Another possible future application of this system,” adds Dr. Shulman-Dauba, “is to perform thousands of medical tests simultaneously, quickly and efficiently.”
Contributed to the research of scientists from the Max Planck Institute in Potsdam, Germany, and the University of Minnesota in the United States.
