A little protein with a big role in building Earth's carbon fixing machinery

An international team of scientists has discovered that a small, low-abundance protein plays a surprisingly big role in assembling carboxysomes—specialized bacterial microcompartments that enable efficient carbon fixation and underpin much of life on Earth. The study, published in Nature Plants, reveals how the shell adaptor protein ApN (also known as CcmN), despite being present at very low abundance, is essential for orchestrating the early stages of carboxysome formation.