Open Wide: Human Mouth Bacteria Reproduce through Rare Form of Cell Division.

One of the most diverse ecosystems on the planet is closer than you think — right inside your mouth. Your mouth is a thriving ecosystem of more than 500 different species of bacteria living in distinct, structured communities called biofilms. Nearly all of these bacteria grow by splitting [or dividing] into two, with one mother cell giving rise to two daughter cells.

New research from the Marine Biological Laboratory (MBL) and the American Dental Association Forsyth Institute (ADA Forsyth) uncovered an extraordinary mechanism of cell division in Corynebacterium matruchotii, one of the most common bacteria living in dental plaque. The filamentous bacterium doesn’t just divide, it splits into multiple cells at once, a rare process called multiple fission. The research is published this week in Proceedings of the National Academy of Sciences.

The team observed C. matruchotii cells dividing into up to 14 different cells at once, depending on the length of the original mother cell. These cells also only grow at one pole of the mother filament—something called “tip extension.”