Miraculous Microbes: They Make Holy Statues “Bleed”—and Can Be Deadly, Too
A sinister bacterium implicated in Catholic miracles and “blood”-tainted polenta also kills coral, insects, and are even are up to no good in your contact lens case.
Serratiamarcescens is a forgotten but ubiquitous bacterium that can produce a red pigment called prodigiosin and likes to hang out as a pink film in the shower grout and toilet bowls of less-than-scrupulously clean homes. The pigment is so persistent that giant amoebas called slime molds that dine on S. marcescens turn red just as flamingoes that eat shrimp turn pink. Yet the picture emerging of this unsung organism is increasingly sinister.