Information overload: assigning genetic functionality in the age of genomics and large-scale screening.

As more and more genome sequences are completed, it is becoming increasingly evident that our understanding of the function of most bacterial gene products is lacking. This is frustrating, particularly in the study of pathogens, where an understanding of the role of individual gene products would probably facilitate the development of novel antimicrobials and vaccines. Recently, we devised a technique known as virulence-attenuated pool (VAP) screening to help assign genetic functionality to gene products that the pathogen Vibrio cholerae requires for colonization. This screen and potential new applications of the VAP technique are discussed here.