Glowing markers of cell death in bananas

Researchers have used genomic sequence comparisons to predict an ocean bacterium’s trophic strategies, which may provide a technique to analyze the diversity of ocean bacteria, many of which are difficult to culture in the lab. Federico Lauro et al. compared the genomes of two common ocean bacteria: the copiotrophic Photobacterium angustum, which lives in warm, nutrient-rich waters and is fast to grow and divide, and the oligotrophic Sphingopyxis alaskensis, which lives in nutrient-poor, Arctic waters and grows more slowly. The authors analyzed the number, patterns, and variations in gene families. In one family, copiotrophic bacteria had many selective transporter proteins to quickly absorb plentiful nutrients, whereas oligotrophic bacteria had a smaller number of highly efficient transporter proteins to extract what little nutrition is available in Arctic oceans. The authors found differences in other genes related to nutrient and energy usage, ref lecting the bacteria’s adaptation to their environments. The authors used their technique to analyze 124 other oceanic bacteria, and found that oligotrophic bacteria outnumbered copiotrophic bacteria in worldwide samples of ocean water, despite the fact that copiotrophic bacteria are easier to culture in the lab. — P.D.