Is life a form of computation?

I love thinking about life as computation. Cells are computers, enzymes are functions, ribosomes are compilers, nucleic acids are source code...

Enzymes in particular are a lot like unix pipelines. An enzyme catalyzes its substrate's conversion into its product which is the substrate of another enzyme. When cells ingest glucose, it flows through the glycolysis metabolic pathway until it becomes pyruvate, and may be reduced even further depending on available resources. It's a huge pipeline of enzymes. They just kinda float around within the cell and randomly perform their tasks when their substrates chemically interact with them. No explicit program exists, it emerges from the system within the cell.

  Cell              - Computer
  Enzyme            - Function / Process / Filter
  Substrate         - Data
  Product           - Data
  Metabolic pathway - Program / Script

I've been playing in my mind with an idea for an esoteric programming language modeled around enzymes. The program defines a set of enzymes which are functions that match on the structure of data, automatically apply themselves to them and produce a modified version of the input which may in turn match against other enzymes. The resulting program metabolizes input by looping over the set of enzymes and continuously matching and applying them until the data is reduced to its final form. If no enzymes match, the output is the unmodified input.