H. pylori's genome sequence was published in 1997. Exploring interactions between proteins reveals biological pathways and helps researchers predict what proteins do. The new research, for instance, offers some clues to H. pylori's success - it infects about half the world's population. The team screened 261 H. pylori 'bait' proteins against a much larger collection of 'prey' protein fragments, coded for in the bacterium's genome. Bait and prey were generated by a yeast that had been modified to grow only if the two bacterial molecules interacted.
Biologists view such interaction as a strong sign that two proteins are functionally related.
Similar maps of protein interactions have already been prepared for yeast and a worm, but in both cases whole proteins were used as prey molecules. The team gave each interaction a score that reflected how strong it appeared and entered the results into a computer to investigate the possible pathways between proteins. One of their discoveries was a connection between proteins believed to be crucial for the synthesis of an enzyme that H. pylori needs to survive in our harshly acidic stomachs. They report their results in Nature 1 . They have found a very large number of interactions.