A new paper suggests a need for a fundamental rethink of the evolutionary path of enzymes, the proteins vital to all life on Earth.

Enzymes catalyze a vast array of biologically relevant chemical reactions even in the simplest living cells but biochemist Dr. Wayne Patrick of University of Otago and colleagues assert that while people tend to imagine evolution as a slow and steady march, from barely functional life forms in the primordial soup towards a modern-day pinnacle of near perfection, that may not be true. 

Instead, they note examples in which enzymes have evolved with lightning speed--over years, rather than eons and provide evidence that many enzymes were better catalysts in the ancient past than they are today. One example of extraordinarily rapid evolution is the emergence of enzymes that modern-day bacteria use to break down human-made antibiotics and pesticides.

"When it comes to enzyme evolution, this is also the textbook version of the events occurring at the molecular level; a smooth and steady trajectory, from barely functional primordial catalysts to the highly active and specific enzymes that we observe today. However, upon closer examination, the reality appears quite different.

"Studying the complexities of enzyme evolution not only provides fundamental knowledge about how life emerged from the primordial soup, but also gives insights into designing proteins with biomedical and biotechnological applications."

Dr Patrick and colleagues at the Department of Biochemistry's Laboratory for Enzyme Engineering and Evolution are currently pursuing such applications, which includes collaborating with leading biotechnology company LanzaTech, which has a microbe that can grow by using harmful gases from industrial plants such as steel mills and oil refineries. They are engineering enzymes to put into this microbe so it can produce useful raw materials that would otherwise have to be made from petroleum.

"This is a great example of the ways in which really fundamental research--carried out with a grant from the Marsden Fund of New Zealand--can translate into applied outcomes in unexpected ways," Patrick says.

 Published in the Journal of the Royal Society Interface.