The Krebs Cycle as Nature’s Original Algorithm

In Transformer, Nick Lane argues that life is not just chemistry, but a system of energy flow, transformation, and information processing. One of the best examples of this idea is the Krebs cycle. Also known as the citric acid cycle, the Krebs cycle shows how biology uses step by step processes that strongly resemble algorithms used in computational biology and artificial intelligence.

The Krebs cycle is a circular metabolic pathway that takes simple molecules derived from food and gradually transforms them into usable energy. Each step is tight

ly regulated, enzyme driven, and dependent on the success of the previous step. This structure is very similar to how algorithms work in computer science, where an input is processed through a defined sequence to produce an output.

From a computational biology perspective, the Krebs cycle can be modeled as a network. Metabolites are nodes, reactions are edges, and enzymes act as regulators. Scientists use computational models to simulate how changes in one part of the cycle affect the whole system. This helps researchers understand diseases, drug interactions, and evolutionary constraints. In this way, metabolism becomes something that can be computed, predicted, and optimized.

Artificial intelligence uses a similar logic. Neural networks process information through layers, adjusting parameters to efficiently convert inputs into outputs. The Krebs cycle also optimizes efficiency. It extracts as much energy as possible from carbon molecules while minimizing waste. Nick Lane emphasizes that this efficiency is not accidental. It is the result of billions of years of natural selection shaping biochemical pathways that work reliably under many conditions.

Seeing the Krebs cycle as an algorithm changes how we think about life. Instead of viewing metabolism as messy chemistry, we can understand it as structured information processing powered by energy. This idea supports Lane’s broader argument that life and intelligence are deeply connected through energy flow. Long before computers existed, cells were already running complex programs, and the Krebs cycle is one of the most important.