In a study published in British science weekly Nature today, a US team has extracted a light-sensing gene from a germ called a cyanobacterium to make the film.
They have stitched it into the cell membranes of Escherichia coli (E coli) bacteria so exposure to red light switches off a gene that controls the production of the bug's black pigment.
As a result, black-and-white images can be "stencilled" onto a mat of the engineered bacteria grown on a plate of protein-rich lab gel.
The resolution and tone scale are extraordinarily good because the screen's definition is on bacterial scale, at up to 100 million pixels per square inch.
The authors from the University of California say their invention could spur "bacterial microlithography" and the creation of new materials made from living organisms.
They say their study could also help unlock fundamental knowledge about how bacteria use gene switches to send signals to each other. abc