In 2007 his team showed that high intracellular levels of manganese(II) in D. radiodurans protect proteins from being oxidized by radiation, and proposed the idea that "protein, rather than DNA, is the principal target of the biological action of in sensitive bacteria, and extreme resistance in Mn-accumulating bacteria is based on protein protection".
En 2007 o seu equipo mostrou que os altos niveis intracelulares de manganeso(II) en D. radiodurans protexen as proteínas da oxidación causada pola radiación, e propuxeron a idea de que "as proteínas, en vez do ADN, son os principais obxectivos da acción biolóxica da radiación ionizante en bacterias sensibles, e a extrema resistencia nas bacterias que acumulan Mn está baseada na protección das proteínas".