by S. Marvin Friedman
Colonization of wheat roots with Azospirillum lipoferum
labeled with the green fluorescent protein (gfp) reporter
Is the current preoccupation of the scientific community with sequencing every genome extant merely an exercise in providing databases for GenBank? Certainly not, for this information also reveals very important characteristics of the organism under analysis. For example, we are at the early stages of a medical revolution that will see affordable individual human genome sequences made available to physicians as part of routine annual check-ups. As the role of various genes involved in health issues becomes even more fully elucidated, such a report will allow the physician to compile a profile of the patient’s susceptibilities to a broad range of diseases. In the case of microbiology, many fresh insights have been derived from genome sequences, including one that I have previously blogged in STC, namely genome reduction as one possible consequence of a bacterium’s commitment to an obligate parasitic lifestyle. Another of my blogs showed that the genome of the 14th century plague bacillus isn’t so different from that of the much less virulent modern strains, indicating that other factors during the medieval era were probably in play. In the paper I am about to discuss, we will see that bacterial genome sequences tell us when and how some bacteria transitioned from aquatic to terrestrial ecosystems.