Feature

Termites Pty (Ltd) the leaders in global cellulolytic biotechnology

With global energy shortages becoming more pronounced, much research is being focused on how to unlock the energy in cellulose, one of the main components of wood.

Typically cellulolytic enzymes break cellulose down into simple sugars which can then be used for instance in a fermentation to produce fuel alcohol. The technology to do this is however still not widely used by humans due to technology deficiencies.

Driving from Lubumbashi to Kolwezi in the Democratic Republic of Congo (DRC) is an interesting experience in many ways. The landscape is generally quite flat, with occasional hills, and is well wooded with trees ranging in height from about 15 metres to 35 metres. These trees represent a lot of cellulose production capacity. Interspersed in these woodlands are large numbers of very distinctive big mounds of soil created by termites. Many of these mounds can be as large as 20 metres across and 5-9 metres high. If one walks in these woodlands, it soon becomes clear that termites are the most significant animals in the woodlands, and their impact is tremendous. It is also abundantly clear that termites have mastered the biotechnology of cellulose conversion.

If one compares termites to bees or ants, one finds that termites have a society far more similar to ours than the other two.

Bees and ants have a society in which a female or females lay eggs and the female gender is generally determined by the presence of two sets of chromosomes. Males are produced by hatching an unfertilised egg, meaning a male only has one set of chromosomes. These highly evolved animals therefore are able to bypass the problems that are associated with having gender determined by a sex chromosome.

In humans as an example, the male Y chromosome is a pathetic chromosome that is being eroded slowly away by mutations, and, many of the worst genetic diseases on Earth are caused by this chromosome as a male will have the female X chromosome from its mother, and the male Y chromosome from its father. If either chromosome has a faulty gene on it, there is no backup on the other chromosome to cover for this.

A female with two X chromosomes on the other hand can have more genetic resilience to mutations as, if one X chromosome has a dysfunctional gene, the other can always cover for this. Hence in humans, men tend to have more genetic illnesses. In more advanced animals, such as bees and ants, the risk of these genetic diseases linked to a male sex chromosome has been minimised by dispensing with the male sex chromosome, and instead opting for the more sensible system where males are unfertilized eggs and females are fertilised eggs.

Hence in a typical beehive, with the social bee, Apis mellifera, the workers and queen are female, and are responsible for egg laying and hive maintenance respectively. The drones are male and their only real function is reproductive. A beehive can survive perfectly well without drones, and only produces them when it has the resources or need to reproduce. In these societies, females store sperm from matings for life, and hence only really need to have contact with males a few times, after which the males are not needed.

Termites on the other hand have a system which is more similar to the human norm, with many types of termites typically having a reproductive pair comprising a queen/s who lays eggs and a king/s who provides sperm to fertilise these eggs, and offspring which are both male and female performing tasks to ensure the smooth operation and growth of the termite colony, and the species.

In the Congo near Kolwezi, many species of termites operate complicated and powerful colonies. Termites have mastered the biotechnology of converting cellulose into energy to power their colonies, and as humans, we will in years to come most probably learn much from these animals on how to do this so that we too may power more of our economy on cellulose.

Cellulose is a major component of most plant matter and, in the Congo, as soon as a leaf, or twig, or tree falls to the ground, the termites quickly harvest the cellulose energy in it. They will also attack living trees and any exposed wood. Some of the termite species in the area have the ability to cultivate a symbiotic fungus, Termitomyces, which is fed a mixture of termite faeces and plant matter. The fungus is cultivated in special galleries deep in the mound where ventilation is provided by carefully constructed tunnels. The fungus grows well on the nutrition provided to it by the termites, and some of this growth is eaten by the termites. This system allows for an incredibly efficient food production system, and the result is that such termites are able to build huge mounds.

Another result of these termites being such effective scavengers of dead plant matter is that very little plant matter gets to stay on the surface of the soil and decompose to enrich the top soil. Hence there is very little difference between soil that is 2cm below the surface and 2 meters below.

The result is that very little nitrogen fixing activity takes place, as the bacteria which fix nitrogen require a source of energy, and in the topsoil this source of energy is typically decaying plant material. The result is that these clay soils are actually very deficient in nutrients and because they contain little organic matter, the soil is easily waterlogged, and agriculture in the area is not very productive.

For us to expand our energy security on the planet we will in years to come have to learn more and more from our ancient friends the termites, who have, since before our ancestors were a twinkle in some strange little creatures eye in the Jurassic period, been using a suite of enzymes to access cellulose as a primary energy source to run their sophisticated social structures.

More information:

Dr Garth Cambray is a techno-entrepreneur and the MD of Makana Meadery

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