At the heart of all life is a code. Our cells use it to turn the information in our DNA into proteins. So do maple trees. So do hammerhead sharks. So do shiitake mushrooms. Except for some minor variations, the genetic code is universal.

It’s also redundant. DNA can code for the same building block of proteins in more than one way. Researchers have long debated what purpose this redundancy serves — or whether it’s just an accident of history.

Thanks to advances in genetic engineering, they can now do more than just argue. Over the past decade, scientists have built microbes with smaller codes that lack some of that redundancy. A new study, published Thursday in the journal Science, describes a microbe with the most streamlined genetic code yet.

Remarkably, the engineered bacteria can run on an abridged code, making it clear that a full genetic code isn’t required for life.

“Life still works,” said Wesley Robertson, a synthetic biologist at the Medical Research Council Laboratory of Molecular Biology in Cambridge, England, and an author of the new study.

Our DNA is built from four different molecular building blocks, called bases: adenine, thymine, guanine and cytosine. A sequence of hundreds or thousands of these bases — known in brief as A, T, C and G — forms a gene. Our cells translate the sequence of bases in genes to make proteins.