Disruption can shed a unique light on difficult issues, giving a fresh urgency and perspective to the challenges of our global community.” It can challenge old assumptions, ignite conversations, activate authorities and expose new possibilities. “But disruption can be a positive – sometimes vital – catalyst for change. ![]() So, positive disruption is a thing, Nigel Rushman says: I draw attention to systems that can be improved and systems that have failed and I showcase the new world of digital transformation, startups and innovators that are part of the disruption of government and NGOs. ![]() ![]() I honestly believe that you have to call out what isn’t working as I do often, through my blogs and through my work as speaker, consultant and in public forums. They saw it coming and they did nothing, until they had no choice.ĭisruption is not a bad thing or something to fear, it just needs to be contextualised in its evolution to drive transformation. It’s also because there are outsiders who will disrupt you – think the Taxi Council and Uber. That’s because we know that the status quo is unacceptable and unsustainable and it is urgent to find another way to deliver better outcomes. When a system is jarred into a pattern of response that is not working it will be disrupted, you can’t just meander along and hope for the best. The other authors on the study are Warshel’s graduate students Pankaz Sharma, Zhen Chu and Mats Olsson.Disruption is not destruction. In particular, this is important for the understanding of so-called “radical reactions” when the bonded atoms are not charged. The finding could have implications for research into biological processes, Warshel said, since “everything that happens in your body, everything, is catalyzed by enzymes.” The electrostatic force between the two charges then helps to cleave the bond. When the bond stretches, the partially charged group comes closer to an oppositely charged area elsewhere in the B12 enzyme. That would appear to rule out an electrostatic intervention by the enzyme.īut Warshel showed that in B12 there is an additional partially charged group attached to one of the key bonded atoms. In B12 enzymes, the key bond between the two parts of the reacting molecule breaks in such a way that neither of the bonded atoms is electrically charged. The resulting electrostatic attraction between the enzyme and the two ends of the bond helps to overcome the force of the bond itself. They do this, according to Warshel’s computer models, by placing a negative charge on the positive end of a chemical bond, and a positive on the negative end. Catalysts lower the activation barrier dramatically. ![]() The trick is a variation on the theory that Warshel previously proposed.Īll reactions have an activation barrier, analogous to the resistance one feels when pulling apart two magnets. “The trick used by B12 enzymes may, in fact, be a very powerful new strategy in enzyme design,” he wrote. He called this “a completely general approach” that could lead to new catalyst formulations for research or industry. Warshel said he solved the problem by showing that B12 enzymes employ a “trick” that enables them to harness electrostatic energy. “To me it was a major problem” that challenged Warshel’s own theory. “To some people it was just a puzzle,” he said. “B12 enzymes have been originally assumed to present what is perhaps the best support for the popular idea that strain energy contributes in a major way to enzyme catalysis,” Warshel wrote in PNAS. Until this study, B12 enzymes represented what Warshel calls “the last bastion” for the strain hypothesis. His latest study, published last month in the Proceedings of the National Academy of Sciences Early Edition, proposes an electrostatic mechanism for catalysis of reactions in vitamin B12 enzymes. Enzymes - proteins that catalyze biological reactions - may be the least understood.Ī popular explanation among chemists and biologists is the “strain hypothesis,” which proposes that an enzyme molecule stretches the reacting bond like a spring, eventually breaking it.Īrieh Warshel, professor of chemistry in USC College, is a leading advocate of an alternate theory that could have wide implications.īased on computer simulations, Warshel believes that enzyme catalysis relies on electrostatic energy to help sever chemical bonds.
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