Simplified Ancestral Enzyme Produces ATP Without Key Amino Acid, Study Finds

Researchers have engineered a simplified version of an ancestral enzyme that can produce ATP, the energy currency of cells, without an amino acid that is essential for the modern enzyme's usual reaction. The enzyme, adenylate kinase, normally relies on a specific amino acid residue, but the simplified version functions without it, suggesting early proteins could have been functional with a reduced set of amino acids. This work, published in a scientific journal, offers insights into how life's molecular machinery may have evolved when fewer amino acid types were available. The findings could inform synthetic biology and the design of minimal enzymes for industrial applications. Early life may have used simpler proteins than previously thought.