Gribbles — why these wood-feasting microbial Vikings might be energy stars

The Village of Breaking Things Down

So it takes a village, as well, to deconstruct the plant or animal, whether the breakdown is being done inside the digestive system, or externally in nature in the breakdown, for example, of a fallen tree. Fungi, bacteria, insects and more all do their work, symbiotically.

To add to the complexity, it turns out that, from a biological point of view, those fungi have more in common, at a cellular level, with a Member of Congress than the bacteria that work right beside them in the breakdown of plant material.

You know, there’s something that feels quite right about the similarities between fungi and Congress. But we’ll come back to that another time.

From a researcher’s point of view, studying the mysteries of the breakdown of biomass into its constituent parts — well, it’s an explosion of complexity to understand all the enzymes and microbial tactics that come into play. How to line up and optimize a human-designed cocktail of microorganisms and processes to effectively duplicate — and even improve on — Mother Nature’s practices?

Well, it is more filled with permutations and alternative paths than face the average Powerball player contemplating the winning path to a $500 million jackpot.

With woods, to focus in on one critical biomass supply, the work of breakdown is generally accomplished by fungi. But current thinking is that it is a host of co-operating fungi that get the job done — some breaking down sugars, followed by a crew that works on cellulose, followed by what has been described as a “lignin-degrading guild” of fungal microbes.

For a long time, one of the critical family of enzymes, the GH7s, that got the job done were believed to be the exclusive property of fungi. Now, they have been found in animals, as well as in protists (um, what exactly are protists? They are a class of one-cellers – some benign, some downright dangerous. Algae, for example, is a protist — and so is the pathogen that causes malaria).

With the expansion of the GH7 universe — there’s been some speculation and hope that in the new host organisms we might find unique characteristics that would help accelerate the breakdown of biomass, or make the process cheaper, or more sustainable.

In today’s Digest, we visit with the gribble, discover why it is a hot subject of research, what peering into its enzyme collection has taught us, the technology used to do so — and the implications for biofuels. Stopping by the Seattle waterfront, the University of York, Portsmouth Harbor, and down where only x-ray microscopes can see — the whole story, for you, by clicking the page links below.