Microbe metabolism
Every living organism balances a budget of sorts — by allocating energy to various parts of its body to fuel essential life processes. Throughout its lifetime, an organism may rebalance this budget to spend more energy on certain processes over others. How an organism spends its energy determines, in large part, its ability to survive in the world, and researchers who study “bioenergetics” are modeling energy use in organisms to understand how populations grow and evolve. Researchers at MIT have now come up with a model for how energy is spent in the smallest, simplest organisms on Earth, ranging from single-celled bacteria to multicellular microbes. The model divides an organism’s possible energy use into two broad categories: growth and reproduction, and maintenance and repair. Based on the size of a given organism, the model accurately predicts what fraction of energy is spent on each category. This information, the scientists say,...