What happens if an incomplete EC number is entered?
PRECISE returns a list of all enzymes that are compatible with the query. Clicking on any member of the list, it further expands until a unique EC number is found. Q: A query with a unique EC number frequently returns several PDB IDs with a additional character. E.g., entering EC number 1.1.1.1 (alcohol dehydrogenase), we get the list as follows: 1B16_A, 1J5R_A, 1JVB_A, and 3BTO_A. What are these? A: Each of these PDB IDs represents a cluster of dehydrogenases that have the same catalytic function and hence the same EC number, but show little similarity to each other. The fifth character in the ID is the chain identifier. For example, the cluster of 1B16 includes different structures of the alcohol dehydrogenase from drosophila lebanonensis, 1J5R from the bacterium thermotoga maritima, 1JVB from the archaeon sulfolobus solfataricus, and 3BTO represents a large group of dehydrogenases from various mammals. While these enzymes have the same function, they diverged to a degree such that t
