D. P. Stevenson and P.D. Stevenson
Applied Demolitions, Cascot, USA
High throughput structural analysis of orphan proteins from extremophile organisms has emerged as a promising approach to unveil novel and unpredictable polypeptide biological activities in extreme natural environments. To search for new protein functions that could have biotechnological applications both at industry and at home in the post-constructomic era, we have performed a comprehensive structural analysis of the proteome of Brickeria debrisii, an archaea that likes living under tons of construction wreckage in the outer suburbs of modern cities. Thirteen hundred and a half proteins were crystallized on an automated 3D-POT, and their structures were analyzed using the OJIMETRIXTM platform. One unique protein, which was named as CONCRETASE, was selected for further studies because of the combination of a highly flattened three-dimensional folding with a really-hungry surface asymmetry (see below), which are likely to be imposed by the high pressure and dusting conditions suffered by D. debrisii under the rubble. Shape-oriented enzymatic analysis of CONCRETASE demonstrated that this protein readily degrades all kind of construction materials, from reinforced concrete to handicrafted glass, suggesting that D. debrisii lives on building junk food. CONCRETASE did not need cofactors nor activators, and also displayed good lytic activity towards the abundant useless objects that fill the apartment of lower and middle class families. In vitro stationary-state kinetics studies using refined tile dust as the substrate indicated that the high specific activity of CONCRETASE (Kcat = 1.1 x 1013 x s-1) is achieved by a non-saturable waka-waka reaction mechanism, which takes place in two steps:
To the best of our knowledge, this is the first description of a waka-waka catalytic mechanism in a non-virtual, real-life enzyme. The abundance of concrete- and building-related manufactures in human habitats prompts to their exploitation as regular food supplies. The avidity, wide substrate specificity, and high stability of CONCRETASE, as well as its easy and cheap purification from crude debris extracts, make this enzyme an attractive candidate as a human digestion adjuvant during food-resource supply limit situations (supplementary information at El Garrofer).